Wuerth Elektronik eiSos and Co KG AMB2220 AMB2220 User Manual Testreport ETS 300 335
Wuerth Elektronik eiSos GmbH & Co KG AMB2220 Testreport ETS 300 335
Users Manual
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Test report no. 18011320 Page 1 of 1
EUT: 2603011021001,
2603011121001
FCC ID: R7TAMB2220
FCC Title 47 CFR Part 15
Date of issue: 2018-05-18
Date: 2017-09-07
Created: P9 Controlled: P4 Released: P1
Vers. no. 1.17
m. dudde hochfrequenz-technik
GmbH & Co. KG
Rottland 5a
51429 Bergisch Gladbach/ Germany
Tel: +49 2207-96890
Fax +49 2207-968920
Annex acc. to FCC Title 47 CFR Part 15
relating to
Würth Elektronik eiSos
2603011021001, 2603011121001
Annex no. 5
User Manual
Functional Description
Title 47 - Telecommunication
Part 15 - Radio Frequency Devices
Subpart C – Intentional Radiators
ANSI C63.4-2014
ANSI C63.10-2013
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Manual
Release 3.12
For Model
26 03 01 1 0 2 100 1 (alias AMB2220)
26 03 01 1 1 2 100 1 (alias AMB2220-1)
SW-V3.5.0
Würth Elektronik eiSos
Phone +49.651.993.550
Internet www.we-online.com/wireless-connectivity
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AMB2220_MA_3_12 Page 2 of 48 Date: 05/2018
Table of Contents
1 Summary ................................................................................................................................ 5
2 Electrical parameters ............................................................................................................ 6
2.1 Operating conditions ......................................................................................................... 6
2.2 Current consumption ......................................................................................................... 6
2.3 Radio parameters ............................................................................................................. 6
3 Dimensions and weight ........................................................................................................ 6
4 Pinout ..................................................................................................................................... 7
5 Serial interface ....................................................................................................................... 8
5.1 UART ................................................................................................................................ 8
5.1.1 Supported data rates .................................................................................................. 8
5.1.2 Supported data format ................................................................................................ 8
5.2 SPI .................................................................................................................................... 8
6 Timing parameters ................................................................................................................ 9
6.1 Reset behaviour ................................................................................................................ 9
6.1.1 Power-on reset ........................................................................................................... 9
6.1.2 Reset via /RESET pin ................................................................................................. 9
6.2 Latencies during data transfer / packet generation ............................................................ 9
7 Operating mode ..................................................................................................................... 9
8 UserSettings ........................................................................................................................ 10
8.1 Difference between volatile and non-volatile UserSettings .............................................. 10
8.2 Factory reset ................................................................................................................... 10
8.3 Available UserSettings .................................................................................................... 10
8.4 Radio parameters ........................................................................................................... 11
8.4.1 Channel .................................................................................................................... 12
8.4.2 Data rate .................................................................................................................. 13
8.4.3 Subnet ...................................................................................................................... 14
8.4.4 Source address ........................................................................................................ 14
8.4.5 Output power level ................................................................................................... 15
8.4.6 Cfg_Flags ................................................................................................................. 16
8.5 UART_Baudrate ............................................................................................................. 16
8.5.1 Example: Set the UART baud rate to 115200 baud .................................................. 16
9 The command interface ...................................................................................................... 17
9.1 Overview ......................................................................................................................... 17
9.2 Requests ........................................................................................................................ 19
9.2.1 CMD_DATAEX_REQ ............................................................................................... 19
9.2.2 CMD_RESET_REQ .................................................................................................. 19
9.2.3 CMD_SET_REQ ...................................................................................................... 21
9.2.4 CMD_GET_REQ ...................................................................................................... 22
9.2.5 CMD_SERIALNO_REQ ........................................................................................... 22
9.2.6 CMD_FWVERSION_REQ ........................................................................................ 23
9.2.7 CMD_RSSI_REQ ..................................................................................................... 23
9.2.8 CMD_FACTORYRESET_REQ ................................................................................. 24
9.2.9 CMD_BOOTLOADER_REQ ..................................................................................... 24
9.2.10 CMD_SET_TMP_CHANNEL_REQ ........................................................................ 25
9.2.11 CMD_SET_TMP_S_ADDR_REQ ........................................................................... 25
9.2.12 CMD_SET_TMP_SUBNET_REQ ........................................................................... 26
9.2.13 CMD_SET_TMP_PWRLVL_REQ ........................................................................... 26
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9.2.14 CMD_SET_OPMODE_REQ ................................................................................... 27
9.3 Indications....................................................................................................................... 28
9.3.1 CMD_DATAEX_IND ................................................................................................. 28
9.3.2 CMD_DATAFRAG_IND ............................................................................................ 28
9.3.3 CMD_STATUS_IND ................................................................................................. 29
10 Low power mode (LPM) .................................................................................................... 30
11 Fragmentation mode ......................................................................................................... 30
12 Duty cycle .......................................................................................................................... 31
13 Quick Start ......................................................................................................................... 32
13.1 Setup ............................................................................................................................ 32
13.2 Start-up example ........................................................................................................... 32
14 Firmware update ................................................................................................................ 35
14.1 Using the STM32 UART bootloader .............................................................................. 35
14.2 Firmware update using SWD ........................................................................................ 36
14.3 Risks of a firmware update ............................................................................................ 36
15 Hardware integration ......................................................................................................... 37
15.1 Measures ...................................................................................................................... 37
15.2 Footprint ....................................................................................................................... 37
15.3 General advice for schematic and layout....................................................................... 38
15.4 Antenna connection ...................................................................................................... 40
15.5 Antenna solutions ......................................................................................................... 40
15.5.1 Lambda/4 radiator .................................................................................................. 41
15.5.2 Chip antenna .......................................................................................................... 41
15.5.3 PCB antenna .......................................................................................................... 41
15.5.4 Antennas provided by AMBER ............................................................................... 41
16 Manufacturing information ............................................................................................... 42
17 Firmware history ............................................................................................................... 43
18 Regulatory compliance information ................................................................................. 44
18.1 Important notice ............................................................................................................ 44
18.2 Declaration of Conformity .............................................................................................. 45
18.3 FCC Compliance statement ........................................................................................ 46
18.4 IC Compliance statement ........................................................................................... 46
18.5 FCC and IC Requirements to OEM integrators ............................................................. 46
18.6 AMB2220 & AMB2220-1 ............................................................................................... 47
19 Important information ....................................................................................................... 48
19.1 Exclusion of liability ....................................................................................................... 48
19.2 Trademarks ................................................................................................................... 48
19.3 Usage restriction ........................................................................................................... 48
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Abbreviations and abstract
CS
Checksum
DC
Duty cycle
Relative frequency reservation period
RF
Radio frequency
Describes everything relating to the wireless transmission
Payload
The real, non-redundant information in a frame/packet
UserSettings
Any relation to a specific entry in the UserSettings is marked
in a special font and can be found in the respective chapter
UART
Universal Asynchronous Receiver Transmitter, allows to
communicate with the module of a specific interface.
Duty cycle
Transmission time in relation of one hour
1% means, channel is occupied for 36 seconds per hour.
Hexadecimal
[HEX]
0xhh
All numbers beginning with 0x are stated as hexadecimal
numbers. All other numbers are decimal.
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1 Summary
The AMB2220 module is designed as a radio sub module for wireless communication between
devices such as control systems, remote controls, sensors etc. and operates on a frequency of
2.4 GHz, the world-wide free available frequency band.
The AMB2220 can be deployed wherever the wireless exchange of small data packets between
two or more parties is required, offering an extremely high range of about 1 km with integrated
antenna (2 km with suitable external antenna) at a data rate of 1.5 kbps
1
. Data rates up to 12
kbps are supported, higher data rates can be developed on request.
A serial interface (UART) is available for communicating with the host system. An SPI interface
can be developed on request.
The Low Power Mode allows energy consumption in sleep mode of about 1 µA. A special
selectable pin can be used for wake-up purposes. If the module is not in Low Power Mode, it is
always in reception over both UART and RF.
The AMB2220 has an integrated microcontroller with a specially designed stack from Würth
Elektronik eiSos, with exclusive access to an integrated RF chip. The microcontroller offers
enough of free space to implement customer specific applications on request.
The control of the module is made over a command interface over UART. Within this, simple
commands can be sent to the module, those are processed and acknowledged. The module is
operational out of the box.
1
The effective range is strongly dependent on external circumstances as buildings, walls, general objects in the line
of sight and objects in the Fresnel zone, temperature and humidity. But it also depends on the data rate and used
antenna solution. The higher the data rate, the poorer the sensitivity, the poorer the range.
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2 Electrical parameters
T = 25°C, Vdd = 2.5V, f = 2.4015 GHz unless otherwise specified
2.1 Operating conditions
Description
min
typ
max
unit
Supply voltage
1.9
2.52
3.6
V
Temperature range
-40
25
85
°C
2.2 Current consumption
Description
min
typ
max
unit
TX current consumption at 10 dBm
37
mA
RX current consumption
9
mA
Low Power
1
µA
2.3 Radio parameters
50 Ohm tethered.
Description
min
typ
max
unit
Output power
8.9
dBm
Input sensitivity at 1.5 kbps
-115
dBm
Frequencies
channel
2.4015
0
2.4775
19
GHz
3 Dimensions and weight
Dimensions: 30.8 x 17 x 4 mm
Weight: 3g
2
For battery powered application the use of 2.5V power supply is recommended. For supply voltages above 2.7V,
the current consumption especially for low power modes rises dramatically.
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4 Pinout
Pin Nr
I/O
Description
1, 3, 33
I
Ground
2
I/O
RF-Pad, for AMB2220-1, connect
with 50 Ohm RF-line
4
I
BOOT0, must be selectable to GND
or VCC for manual firmware update
over UART. Application start-up
when level is low. Has internal 10 kΩ
pull down.
7
I
Power Supply, typ. 2.5V
8
I
/Reset, low active,
has internal 10 kΩ pull up.
Plan to leave open or pull down for
HW-reset and manual firmware
update.
10, 20
I
Wakeup-Pin, low active
See chapter 10.
22
O
UART TX Data,
for manual firmware update this line
needs to be connected to a PC
(using an according usb to serial
converter)
23
I
UART RX Data,
for manual firmware update this line
needs to be connected to a PC
(using an according usb to serial
converter)
17
O
LED_TX, can be disabled/enabled.
See chapter 8.4.6
18
O
LED_RX, can be disabled/enabled.
See chapter 8.4.6
19
I
BOOT1, must be selectable to GND
or VCC for manual firmware update
over UART. Application start-up
when level is low. Has internal 10 kΩ
pull down.
Others
Reserved for coming features and
production, do not connect
Figure 1: Pin Numbers
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5 Serial interface
5.1 UART
5.1.1 Supported data rates
The default data rate is 9600 baud. At this data rate the module is always able to wake up from
sleep without any data loss. This ensures maximal power and speed efficiency.
Since the UART speed is derived from a digitally calibrated oscillator, this may result in
variations of up to ± 2 %.
5.1.2 Supported data format
The following data format is supported: 8 bits, No parity and 1 stop bit (“8N1”).
5.2 SPI
A 3 or 4 wire SPI slave interface can be developed on request.
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6 Timing parameters
6.1 Reset behaviour
The module will signalize over UART with a CMD_STATUS_IND when it is ready. Until then, no
UART communication should be exchanged.
A full module start-up after CMD_RESET_REQ or using the Reset-Pin can take up
to 1s.
6.1.1 Power-on reset
After switching the supply voltage on and releasing the /RESET pin (if wired), the time until the
module is ready for operation can last up to 1s.
6.1.2 Reset via /RESET pin
To force a module restart by means of the /RESET pin, it must first be drawn to low level for at
least 10 ms and then reverting back to high level (e.g. by the internal pull-up resistor).
After going back to high level the µC will perform the start-up procedure.
During this time, the processor clock-rate will be calibrated, which takes anyway between 2 and
20 ms depending on the supply voltage and temperature.
Recommended procedure: Wait for CMD_STATUS_IND over UART after the /Reset pin is high
again.
6.2 Latencies during data transfer / packet generation
The data transfer is always buffered, i.e. data received via UART is buffered in the module until
a specific event occurs. Subsequently, the UART reception is interrupted until the response of
the module and the payload data is passed to the internal memory of the wireless transceiver.
The wireless transmission starts as soon as the complete data is available in the transceiver
memory, which has to be initialized internally. The radio connection itself is a half-duplex
channel based connection.
On the receiver side, the FIFO is read as soon as an incoming and intact packet is detected.
7 Operating mode
The module can be used in command. It reacts on commands by the host system connected
over UART. The commands follow a strict scheme and mostly return a response, which can be
processed by the host for connection control and timing. More information can be found in
chapter 8.5.
The command mode allows quick changes of settings with minimal effort and response time.
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8 UserSettings
8.1 Difference between volatile and non-volatile UserSettings
The so called UserSettings are stored permanently into the internal flash of the module. At
start-up, these UserSettings are loaded into volatile settings, so called runtime settings. The
user setting are accessed by the CMD_SET_REQ command. With the CMD_SET_TMP_xxx_REQ
command set, these runtime settings can be changed, without changing the default
UserSettings in the non-volatile memory. Possible changed values of the runtime settings are
lost after the module is powered off or restarted as they are replaced by the UserSettings upon
module start-up.
8.2 Factory reset
To allow experimentation and furthermore to reset the module in a known state, the
UserSettings can be reset to factory defaults, which means, all UserSettings are set to default
value. For the corresponding command, refer to chapter 9.2.
This factory reset must not be mixed up with the factory setting which contain e.g. Hardware
Revision of the Module and the serial number and product identifier (PID).
8.3 Available UserSettings
The non-volatile settings listed in the following table can be modified by means of specific
commands in the configuration mode (CMD_SET_REQ) of the module. These parameters are
stored permanently in the module's flash memory. All available settings are described on the
following pages.
After changing the UserSettings parameters, a reset is required before they become
applied. After the reset, the new UserSettings will be loaded into the runtime settings.
The validity of the specified parameters is not verified. Incorrect values can result in
device malfunction!
If RF settings are not valid, the default values are used without host or user
notification.
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Designation
Reference
chapter
Valid range
Default
value
Memory position /
Offset
Size [bytes]
RF_Channel
8.4.1
0 - 19
6
0x00
1
RF_Rate
0
1 - 7
1
0x01
1
RF_Subnet
0
1 - 255
169
0x02
1
RF_Address_Source
8.4.4
0 - 255
0
0x03
1
RF_Power_Level
0
0 - 10
10
0x04
1
Cfg_Flags
8.4.6
0 - 255
9
0x05
1
UART_Baudrate
8.5
300 - 115200
9600
0x3C
4
Table 1: Overview of non-volatile UserSettings (all values are decimal)
8.4 Radio parameters
The behaviour of the radio transmitter / receiver can be influenced by selecting and/or changing
RF-parameters which can be stored permanently or temporarily.
User setting
Description
Reference chapter
RF_Channel
Operating channel
8.4.1
RF_Rate
Data rate over RF
8.4.2
RF_Subnet
Division of available channels
8.4.3
RF_Address_Source
Address of current module
8.4.4
RF_Power_Level
Output power level
8.4.5
Table 2: Radio parameters description overview
The radio parameters must be chosen with caution, as they may influence conformity and/or
performance. That the AMB2220 is certified means, that measured on the EV-Board all
requirements of the corresponding norms (see chapter 18.2) are met.
However decisive for the end product is the real radiated power. Using the RF-pad with an
external antenna it is obvious, that the radiated power depends on the selected antenna and the
wiring toward, and that it is not implemented in the certification of the AMB2220. But also for the
on-board chip antenna the radiated output power is influenced by the surroundings, especially
metal, and also by the quality of the power supply and possible disturbances. So it has to be
pointed out, that certification does only apply for the module itself, the conformity of the end
product must be stated by the manufacturer of the end-product.
The frequency channels of the module can be selected from a 4 MHz raster. All channels can
be used by parallel networks, as they are not overlapping, see Figure 2. Off course
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interferences may occur when two devices are comparably close to each other (less than 2
meters)
Figure 2: Spectrum of two signals next to each other, 72 kbps data rate (highest possible).
All channels meet the requirements of the EN 300 440 and may be selected with highest power
settings. For generic use there are no requirements regarding a duty cycle.
8.4.1 Channel
The channel can be selected by changing the non-volatile user setting RF_Channel.
This value can also be temporarily changed.
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Band
Channel
Frequency
RF_Channel
[MHz]
2400 MHz – 2483.5 MHz
output power ≤ 10 dBm
channel separation ≤ 4 MHz
0
2401.5
1
2405.5
2
2409.5
3
2413.5
4
2417.5
5
2421.5
6 (default)
2425.5
7
2429.5
8
2433.5
9
2437.5
10
2441.5
11
2445.5
12
2449.5
13
2463.5
14
2457.5
15
2461.5
16
2465.5
17
2469.5
18
2473.5
19
2477.5
Table 3: RF Channel overview
8.4.2 Data rate
Data rate [kbps]
RF_Rate
Sensitivity [dBm]
1.5
1 (default)
-115
3
2
-113
6
3
-111
12
4
-107
24
5
-102
48
6
-98
72
7
-96
Table 4 : Selectable data rates
The sensitivity in the receiver is an essential parameter for the range of the module. A lower
sensitivity results in a higher range.
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8.4.3 Subnet
In each channel up to 248 different subnets can be defined. Only modules in the same subnet
and same RF_Channel can communicate with each other. Inter subnet communication (i.e. a
communication from one subnet “a” into another subnet “b”, where a != b) is not possible.
Caution: Using different subnets does not avoid radio collisions as it does not avoid overlaying
of two signals at the same time in the same radio channel.
The default subnet parameter RF_Subnet is 0xA9 (decimal: 169).
This value can also be temporarily changed.
Due to hard- and software resolution, the following subnets are reserved and shall not
be selected by the user!
The selected subnets are not checked by the firmware.
Hexadecimal
Decimal
0x00
0
0x30
48
0x33
51
0x63
99
0x66
102
0x92
146
0x99
153
0xCC
204
Table 5: Not allowed subnets
8.4.4 Source address
This address defines the address of the current module and it is copied into sending RF packets
to identify the sender. It is also used to filter incoming RF packets (i.e. decide whether an
incoming packet is supposed to be received by the current module).
To define the source address, change the user setting RF_Address_Source to any address
in the available range. A subnet shall not contain multiple modules with the same address and
in radio range to each other.
The default address is 0x00 (decimal 0).
This value can also be temporarily changed.
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Remember that 0xFF (decimal 255) is the broadcast address.
Any module in range on that radio channel and on that same subnet will receive this
packet.
8.4.5 Output power level
The output power level can be adapted through the user setting parameter RF_Power_Level.
This value can also be temporarily changed.
The default power level is 10 (0x0A). The given DC total current consumption includes radio IC
and µC consumption.
Power level
RF_Power_Level
Output power*
[dBm]
DC total current consumption
[mA]
10
8.9
33.4
9
8
26.5
8
6.8
22.95
7
5.95
20.69
6
4.59
19.2
5
3.5
18.92
4
2.6
17.39
3
1.5
15.93
2
0.9
14.01
1
-0.04
13.36
0
-1.14
12.65
* Measured in a cable-bound environment. Results may vary in customer application, different antennas and
with different VCC values.
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8.4.6 Cfg_Flags
8-bit field in which the use of individual pins, functions or signals can be disabled. Table 6
represents a description of the respective flags.
To use multiple settings, add the bit values (logical OR) and choose the result as value for
Cfg_Flags.
The default value of Cfg_Flags is 0x09 (9 decimal).
Bit no.
Bit value
Description
0
0x0001 (1)
If enabled (‘1’), Pin 17 outputs “high” when transmitting a packet
(LED_TX) and Pin 16 outputs “high” when receiving a packet over
RF (LED_RX).
1
0x0002 (2)
If enabled (‘1’), the fragmentation mode is enabled (see chapter 11).
2
0x0004 (4)
Select either Pin 10 to be the WakeUp-Pin (Bit 2 to ‘0’) or Pin 20 (Bit
2 to ‘1’).
3
0x0008 (8)
If enabled (‘1’), the reception of single packet fragments is indicated
using the CMD_DATAFRAG_IND. This bit is only active if
fragmentation mode is also enabled (Bit 1 of Cfg_Flags = ‘1’).
4 to 15
0x0010 to
0x8000
Reserved, must be set to ‘0’ to prevent conflicts in the future.
Table 6: Config Flags
8.5 UART_Baudrate
This 4-byte field defines the UART baud rate used by the module. In the CMD_SET_REQ it has to
be entered as LSB first.
At module start-up, the default UART baud rate is used, if the configured baud rate is invalid.
8.5.1 Example: Set the UART baud rate to 115200 baud
Enter the CMD_SET_REQ with offset 0x3C and the value 0x0001C200 (=115200). A conversion
to LSB first notation gives 0x00C20100 to be used as parameter.
Start Signal
Command
Number of
Parameters + 1
Offset
Parameter
CS
0x02
0x09
0x05
0x3C
0x00 0xC2
0x01 0x00
0xF1
Response: Success
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x49
0x01
0x00
0x4A
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9 The command interface
With firmware version, 3.0.0 a new more flexible command interface was introduced.
Please note that the module performs a SW-reset if a serious error condition occurs.
In this case a CMD_STATUS_IND is output by the UART, as it is done after each
restart of the module. All volatile (“temporary”, “runtime settings”) parameters are lost
and reverted to the their defaults.
9.1 Overview
The commands can be divided into three types, the requests, the responses (to a request) and
the indications.
Requests are sent by the host and trigger an answer from the module, which is named
“Response”.
Indications are spontaneous data packets from the module to the host, which states i.e. an
incoming radio packet, they do not need an acknowledgement from the host.
The communication with the module occurs in form of predefined commands. To improve
efficiency, several commands have been reduced to an absolute minimum of processing time.
These commands must be sent in telegrams according to the format described in Table 7.
Start signal
Command
Length
Payload
Checksum
Table 7: Telegram format of a command packet
Start signal: 0x02 (1 byte)
Command: One of the predefined commands according to chapter 9.2 (1 byte)
Length: Number of bytes in Payload (1 byte)
Payload: Command specific payload (i.e. data to send, or parameter to configure) (Length
bytes)
Checksum: Byte wise XOR combination of the preceding fields including the start signal,
i.e. 0x02 ^ Command ^ Payload (1 byte)
The Response is stated as shown in Table 8.
Start signal
Command | 0x40
Length
Payload
Checksum
Table 8: Telegram format of a response
Start signal: 0x02 (1 byte)
Command | 0x40: 0x40 OR combination with the command of the request (1 byte)
Length: Length of the following Payload (1 byte)
Payload: Contains the requested information (i.e. parameter) or the status
(Acknowledgement) of the previous request.
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Checksum: Byte wise XOR combination of the preceding fields including the Start Signal,
i.e. 0x02 ^ Command | 0x40 ^ Payload (1 byte)
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9.2 Requests
The command interface indirectly implements a type of flow control:
There must not be two or more active commands at the same time. Therefore, the host must
implement the following sequence:
Send a command.
Wait for the command’s response or till a timeout of 1 second is hit (in case of
fragmentation the timeout must be adopted to the RF bitrate thus resulting in a higher
timeout of up to 5 seconds).
A command that does not response but runs into the timeout must be handled as not
received by the module. This can happen because of invalid commands, a wrong
checksum or bit errors on the UART.
Receive any CMD_STATUS_IND message and handle it accordingly. These spontaneous
messages may also occur while waiting for a response of a previous command.
9.2.1 CMD_DATAEX_REQ
This command serves data transfer in a network with several parties. Both, the radio channel to
be use and the destination address (depending on the parameterized addressing mode) are
specified along with the command. The number of payload data bytes is limited to 26 bytes.
The two parameters radio channel and destination address will replace the currently selected
temporary value in the runtime settings.
With fragmentation enabled (see chapter 11) a limit of up to 240 bytes is usable.
Format:
Start Signal
Command
Payload length +1
Addr.Target
Payload
CS
0x02
0x01
1 Byte
1 Byte
Payload length
1 Byte
Response:
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x41
0x01
1 Byte
1 Byte
Status:
0x00: Request successfully received and processed, packet has been sent
0x01: Error during processing
9.2.2 CMD_RESET_REQ
This command triggers a software reset of the module. The reset is performed after the last bit
of the response was transmitted to the host.
Format:
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Start Signal
Command
Length
CS
0x02
0x05
0x00
0x07
Response:
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x45
0x01
1 Byte
1 Byte
Status:
0x00: Request successfully received and a reset will follow this response
0x01: Error during processing
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9.2.3 CMD_SET_REQ
This command enables direct manipulation of the parameters in the module’s non-volatile
UserSettings . The respective parameters are accessed by means of the memory positions
(Offset) described in Table 1.
You can modify individual or multiple consecutive parameters in the memory at the same time.
The sum of memory position and forwarded data has to be less than the total size of the
UserSettings (max. 64 Bytes). Otherwise the package is not acknowledged or processed.
Parameters of 2 or more bytes (e.g. UART_Baudrate) have to be transferred with the least
significant byte (LSB) first unless noted otherwise for a specific parameter.
The changed parameters only take effect after a restart or a reset of the module.
This can be done by a CMD_RESET_REQ.
Caution: The validity of the specified parameters is not verified. Incorrect values can
result in device malfunction!
To save the parameters in the flash memory of the module, the particular memory
segment must first be flushed entirely and then restored from RAM.
If a reset occurs during this procedure (e.g. due to a supply voltage drop), the
entire memory area may be destroyed.
In this case, the module may no longer be operable, which means that the firmware
must be re-installed via the JTAG, SWD interface or UART Bootloader.
Recommendation: First verify the configuration of the module by reading the current
settings with a CMD_GET_REQ and only write a CMD_SET_REQ if required.
Format:
Start Signal
Command
Number of
Parameters + 1
Offset
Parameter
CS
0x02
0x09
1 Byte
1 Byte
Num. of Bytes
1 Byte
Response:
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x49
0x01
1 Byte
1 Byte
Status:
0x00: Request successfully received and processed
0x01: Error during processing
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9.2.4 CMD_GET_REQ
This command can be used to query individual or multiple UserSettings parameters. The
requested number of bytes from the specified memory position are returned.
You can query individual or multiple consecutive parameters in the memory at the same time.
The sum of the memory position and requested data must not be more than the total size of the
UserSettings (max. 64 Bytes). Otherwise no response will be returned.
Parameters of 2 or more bytes will be transmitted LSB first unless noted otherwise in their
parameter description.
Format:
Start Signal
Command
Length
Offset
Number of Parameters
CS
0x02
0x0A
0x02
1 Byte
1 Byte
1 Byte
Response:
Start Signal
Command |
0x40
Number of
Parameters +1
Offset
Parameter
CS
0x02
0x4A
1 Byte
1 Byte
Num. of Parameters
1 Byte
9.2.5 CMD_SERIALNO_REQ
This command can be used to query the individual serial number and product ID (PID) of the
module.
Format:
Start Signal
Command
Length
CS
0x02
0x0B
0x00
0x09
Response:
Start
Signal
Command | 0x40
Length
PID
Serial Number
(MSB first)
CS
0x02
0x4B
0x04
1 Byte
3 Bytes
1 Byte
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9.2.6 CMD_FWVERSION_REQ
This command is used to request the firmware version of the module. The main version number
is returned first, followed by the secondary version number and the revision number.
Format:
Start Signal
Command
Length
CS
0x02
0x0C
0x00
0x0E
Response:
Start Signal
Command | 0x40
Length
Firmware Version
CS
0x02
0x4C
0x03
3 Bytes
1 Byte
9.2.7 CMD_RSSI_REQ
This command returns the RX level of the last received packet determined by the transceiver IC
in the form of a signed two's complement. The relationship between the applied RF power, PIN
at the antenna pin and the value given by the RSSI can be expressed as:
PIN [dBm] = -120 dBm + RSSI byte * 8dBm , for -105 dBm < PIN < -60 dBm
If no packet was received yet the return value will be 0x00.
Due to this, the RSSI level has a resolution of 8 dBm. The accuracy of the RSSI is not
guaranteed, and is provided for test purpose only.
Format:
Start Signal
Command
Length
CS
0x02
0x0D
0x00
0x0F
Response:
Start Signal
Command | 0x40
Length
RSSI
CS
0x02
0x4D
0x01
1 Byte
1 Byte
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9.2.8 CMD_FACTORYRESET_REQ
This command resets all UserSettings to its factory settings. This command automatically
initiates a restart, which means that all temporary and non-volatile settings are lost.
Format:
Start Signal
Command
Length
CS
0x02
0x11
0x00
0x13
Response:
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x51
0x01
1 Byte
1 Byte
Status:
0x00: Request successfully received and processed
0x01: Error during processing (No reset neither)
9.2.9 CMD_BOOTLOADER_REQ
This command resets the module and starts the internal Bootloader, such that a new firmware
can be flashed (see chapter 14).
To start the AMB2220 application after this command has been used, a reset is required (using
the RESET Pin).
Format:
Start Signal
Command
Length
CS
0x02
0x12
0x00
0x10
Response:
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x52
0x01
1 Byte
1 Byte
Status:
0x00: Request successfully received and processed, Bootloader can be accessed after
automatic reset
0x01: Error during processing
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9.2.10 CMD_SET_TMP_CHANNEL_REQ
This command changes the runtime setting of the RF channel to a specific value.
This will not change the UserSettings which means, this setting is lost when the module
is restarted.
The channel byte is valuable from ‘0x00’ (0) to ‘0x13’ (19). Check Table 3 for more information
about the channel assignment.
Format:
Start Signal
Command
Length
Channel
CS
0x02
0x20
0x01
1 Byte
1 Byte
Response:
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x60
0x01
1 Byte
1 Byte
Status:
0x00: Request successfully received and processed
0x01: Error during processing
9.2.11 CMD_SET_TMP_S_ADDR_REQ
This command changes the runtime setting source address to a specific value.
This will not change the UserSettings which means, this setting is lost when the module
is restarted.
The address source byte is valuable from ‘0x00’ (0) to ‘0xFE’ (254), 0xFF (255) is the broadcast
address which shall not be used as a source address.
Format:
Start Signal
Command
Length
Addr. Source
CS
0x02
0x21
0x01
1 Byte
1 Byte
Response:
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x61
0x01
1 Byte
1 Byte
Status:
0x00: Request successfully received and processed
0x01: Error during processing
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9.2.12 CMD_SET_TMP_SUBNET_REQ
This command changes the runtime setting of the RF subnet to a specific value.
This will not change the UserSettings which means, this setting is lost when the module
is restarted.
The subnet byte is valuable from ‘0x00’ (0) to ‘0xFF’ (255), but due to restrictions of the RF chip,
the following subnets cannot be used:
0x00 (0), 0x30 (48), 0x33 (51), 0x63 (99), 0x66 (102), 0x92 (146), 0x99 (153) and 0xCC (204).
Format:
Start Signal
Command
Length
Subnet
CS
0x02
0x22
0x01
1 Byte
1 Byte
Response:
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x62
0x01
1 Byte
1 Byte
Status:
0x00: Request successfully received and processed
0x01: Error during processing
9.2.13 CMD_SET_TMP_PWRLVL_REQ
This command changes the runtime settings of the RF power level to a specific value.
This will not change the UserSettings which means, this setting is lost when the module
is restarted.
The power level byte is valuable from ‘0x00’ (0) to ‘0x0A’ (10).
Format:
Start Signal
Command
Length
Power Level
CS
0x02
0x23
0x01
1 Byte
1 Byte
Response:
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x63
0x01
1 Byte
1 Byte
Status:
0x00: Request successfully received and processed
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0x01: Error during processing
9.2.14 CMD_SET_OPMODE_REQ
This command lets the module enter the Low Power Mode (LPM). For further information about
the LPM, see chapter 10.
Format:
Start Signal
Command
Length
LPM
CS
0x02
0x28
0x01
0x01
0x2A
Response:
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x68
0x01
0x01
0x6A
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9.3 Indications
9.3.1 CMD_DATAEX_IND
This indication occurs when a valuable radio packet has been received, successfully processed
and assigned. It returns all information of the RF packet. No validation from the host is needed.
This indication represents the opposite of CMD_DATAEX_REQ.
The received RSSI byte has to be interpreted as followed:
PIN [dBm] = -120 dBm + RSSI byte * 8dBm , for -105 dBm < PIN < -60 dBm
Due to restrictions of the RF chip, the RSSI level has a resolution of 8 dBm.
The field Addr. Source contains the source address from the radio frame, that was selected by
the sender of this frame.
Format:
Start
Signal
Command
Payload
Length + 2
Addr.
Source
Payload
RSSI
CS
0x02
0x81
1 Byte
1 Byte
Payload Length
1 Byte
1 Byte
9.3.2 CMD_DATAFRAG_IND
This indication occurs when a valuable radio packet fragment has been received successfully. It
returns the address of the sending device (Addr. Source), the sequence number of the RF
packet, the fragment number of the current RF packet and the fragment number of the last RF
packet that has to be received to complete the full RF packet.
This message can enabled or disabled using the Cfg_Flags.
The full RF packet is indicated using the CMD_DATAEX_IND as soon as the last packet fragment
has been received.
Format:
Start
Signal
Command
Length
Addr. Source
Sequence
Number
Fragment
Number
Number of last
Fragment
CS
0x02
0x82
0x04
1 Byte
1 Byte
1 Byte
1 Byte
1 Byte
If a CMD_DATAFRAG_IND has been received, we strongly recommend to wait for the
packet completion before performing other actions with the module. The module
reception has been completed as soon as CMD_DATAEX_IND was sent to the host or
the timeout occurred.
In case of error, e.g. if one or several packet fragments have been lost during
transmission and thus no CMD_DATAEX_IND was sent, the module reverts to
operate in normal mode after 500ms.
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9.3.3 CMD_STATUS_IND
This indication shows the current state of the module, when module enters or leaves Low Power
Mode (LPM).
Format:
Start
Signal
Command
Payload Length
Status
CS
0x02
0xC0
0x01
Payload Length
1 Byte
Status:
0x00: Run mode
0x01: Low Power Mode
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10 Low power mode (LPM)
This mode sets the module into a sleep deep mode, where it consumes as few as possible
energy. To enter this mode, it is necessary to give the module the right command
CMD_SET_OPMODE_REQ. In this mode, the module is completely unresponsive to external
influences. The only way to wake up the module is by giving a falling edge to the WakeUp-pin,
which is either Pin 10, or Pin 20, depending on the user setting Cfg_Flags.
When the module is not in Low Power Mode, it is in Run Mode.
11 Fragmentation mode
In normal mode the payload of a data packet can be maximal 26 bytes. To allow the
transmission of larger data packets the fragmentation mode was introduced (enabling via
Cfg_Flags, see Chapter 8.4.6). Using this mode data packets up to 240 bytes can be
transmitted by splitting the data packet into fragments and sending the fragments of appropriate
size one after each other. On the receiver side, the packet fragments are detected and
combined to the full packet after all data fragments have been received successfully.
To experience maximum flexibility the user shall prefer implementing the fragmentation in his
host and use the 26 byte MTU (maximum transfer unit).
Sender:
The time needed to send a fragmented packet consists of the time the single fragments are
transmitted (see in chapter 12) plus the timeouts between the single transmissions. After the
successful transmission a response on the CMD_DATAEX_REQ is printed via UART.
Receiver:
Depending on the Cfg_Flags a CMD_DATAFRAG_IND message is sent via UART indicating the
reception of single packet fragments to inform the user to wait for the packet completion.
To be able to send and receive fragmented packets over RF both the sending and
receiving device have to operate in fragmentation mode. Devices not in fragmentation
mode will discard RF packets that are fragmented.
In fragmentation mode there is a much higher probability of RF packet collisions. If
one or several fragments are lost during transmission, the whole data packet is
discarded.
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12 Duty cycle
The fragmentation mode allows the transmission of larger data packets over RF. Thus there is
an increased risk of exceeding the duty cycle, if existent. The time [s] the channel is blocked
when sending a complete packet containing bytes using the data rate [kbps] can be
calculated as:
A packet with maximum size of 240 bytes would need 2.13 s, when sending it in fragmentation
mode using the lowest data rate of 1.5 kbps. This means, with a duty cycle of 1% (36s per
hour), only 16 packets of maximum size could be sent without violation of the duty cycle
restrictions.
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13 Quick Start
Please note that the AMB2220 (firmware version 3.0 or newer) are not RF-compatible
with modules using older firmware versions (2.x or 1.x).
13.1 Setup
To start communication between network participants, make sure the participants are set up
equally (but the setting of source address in case directed messages shall be used):
Out of the box, all the modules are set up in factory settings and are ready to use.
To reset to factory settings, use the command CMD_FACTORYRESET_REQ.
The send procedure can be started using the command CMD_DATAEX_REQ. The
receiving module/s will state the incoming packet with a CMD_DATAEX_IND.
To change settings temporarily (until next reset of module), use the command
CMD_SET_TMP_xxx_REQ. Make sure, receiver and sender are using the same channel
and the same subnet. Make sure, the sending packet has the right receiving address.
Use the following examples to start the communication.
13.2 Start-up example
The following set up is needed:
Both network partners are out of the box set to default settings, so that both modules
have the same default address. This should be changed at start-up.
Both modules are connected to a respective host over UART. This can for example be a
PC which has a terminal program running and the respective COM port opened (in case
that the module is attached to the right converter as in the AMB2220-EV). Otherwise,
this can be a separate microcontroller.
Both modules must be set up in a valid range, at least with a distance of 1 meter, and
power supplied.
UART parameters need to be set to 9600 baud 8n1 (see chapter 5).
As the module is reacting on commands, both AMB2220 are now in receiving mode (both RF
and UART). We first give the receiver the new address “2”, changing the respective user setting
with offset 3 and the size of 1 byte (see Table 1).
Use CMD_SET_REQ with the parameters: (see 9.2.3) from Host 2 to receiver
Start
Signal
Command
Number of
Parameters + 1
Offset
Parameter
CS
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0x02
0x09
0x02
0x03
0x02
0x08
Over UART to Host 2, we get the response
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x49
0x01
0x00
0x4A
which states that the transmission over UART was right and the user setting has been
set right.
Now we reset the module for applying this change (see chapter 8.1). For the reset, we
either use the Reset-Pin or the command CMD_RESET_REQ
Start Signal
Command
Length
CS
0x02
0x05
0x00
0x07
As response, we get the acknowledgement
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x45
0x01
0x00
0x46
To make sure that the user setting has been set correctly, we can check this using the
CMD_GET_REQ (see 9.2.4)
Start Signal
Command
Length
Offset
Number of Parameters
CS
0x02
0x0A
0x02
0x03
0x01
0x08
So we get the response:
Start Signal
Command |
0x40
Number of
Parameters +1
Offset
Parameter
CS
0x02
0x4A
0x02
0x03
0x02
0x4B
and we know that the parameter on offset 0x03 is “2”, the source address we wanted to
plant.
We can now start the communication with the module named sender over Host 1 using
CMD_DATAEX_REQ with the parameters “2” for the target address which we just set, and
a payload up to 26 byte, for example “HELLO”. It should be remarked that the packet
over RF is always 26 bytes of size as the RF chip only supports fixed size packets.
Of course we have to convert ASCII letters “HELLO” in a binary way which gives the
following bytes:
0x48 0x45 0x4C 0x4C 0x4F
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Start Signal
Command
Payload
length +1
Addr.Target
Payload
CS
0x02
0x01
0x06
0x02
0x48 45 4C 4C 4F
0x45
As a result, we get an response from the sender (Host 1)
Start Signal
Command | 0x40
Length
Status
CS
0x02
0x41
0x01
0x00
0x42
At the same time, the receiver (Host 2) gets the packet, evaluates it, checks the address
checksums and states the incoming packet over UART with an CMD_DATAEX_IND:
Start
Signal
Command
Payload
Length + 2
Addr. Source
Payload
RSSI
CS
0x02
0x81
0x07
0x00
0x48 45 4C 4C 4F
0x09
0xCF
Note: the RSSI value is dependent on your setup such as the used RF output power distance
between Host 1 and Host 2 and antenna setup.
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14 Firmware update
To update the firmware of the AMB2220 the internal Bootloader of the STM32 microcontroller or
the SWD interface (together with an according Flasher hardware) has to be used.
The memory area of the factory settings must not be deleted or overwritten during a
firmware-update:
Factorysetting start address (in EEPROM) 0x0808 0000
Factorysetting stop address (in EEPROM) 0x0808 001F
14.1 Using the STM32 UART bootloader
Please refer to ST Microelectronic Application Notes AN3155 and AN2606 for Bootloader
commands and syntax in case you plan your own implementation of accessing the Bootloader.
The UART baud rate in Bootloader mode can be selected between 1200 and 115200 baud,
“8E1”. We recommend 115200 baud.
To use the internal Bootloader the following pins need to be accessible with different logic
levels:
BOOT0 (can be neglected for firmware 2.0.0)
BOOT1 (can be neglected for firmware 2.0.0)
BOOT0
BOOT1
Function
0
(GND)
0 or 1
Normal start-up, the firmware starts
1
(VCC)
0 (GND)
Bootloader starts after a reset, a new firmware can be flashed
over UART1 and the ST Bootloader Protocol.
RESET needs to be pulled to GND for a short time (>10ms) to perform a reset of the
device
UART1_RX, needs to be connected to a PC by means of a TTL to USB-Converter, e.g.
“FTDI TTL-232R-3V3”
UART1_TX, needs to be connected to a PC by means of a TTL to USB-Converter
If a firmware 2.0.0 or newer is currently running on the AMB2220 the command
CMD_BOOTLOADER_REQ is available and can be used to reboot the internal microcontroller so
that the Bootloader is selected without using BOOT0 and BOOT1 and the RESET pins. After
receiving the confirmation bytes the Bootloader is selected and can be started using the so
called “USART Bootloader code sequence” (see AN3155).
You can find the reference PC implementation of ST on the ST Homepage under the part
number “STSW-MCU005”.
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An easy-to-use AMBER implementation of STM32 Firmware Updater optimized for AMB2220 is
available through our homepage (account needed). This software will prevent the factory
settings to be changed as well as it supports access to the UserSettings over a GUI.
14.2 Firmware update using SWD
Please refer to the AMB2220 evaluation board manual for a reference design with SWD
connector.
We recommend using a SEGGER J-Link hardware for flashing the device.
The microcontroller-type to be connected to is a ST Microelectronics STM32L151CB.
14.3 Risks of a firmware update
If the firmware update procedure fails the microcontroller can end in a state where the
application (in our case the AMB2220 firmware) is no longer working (due to erased or wrong
written memory segments).
In this case only a firmware-update using BOOT0 + BOOT1 + RESET or the SWD update can
be performed to access the module’s Bootloader again.
This is the reason why we strongly recommend to have the BOOT0, BOOT1, RESET,
UART_TX and UART_RX pins accessible to be switched to alternative levels or functions.
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15 Hardware integration
15.1 Measures
Figure 3: Dimensions [mm]
15.2 Footprint
Figure 4: Footprint [mm]
To avoid the risk of short circuits between VCC (or signal lines) and GND, a minimum
clearance of at least 14 mm between the opposing pad rows has to be maintained
respectively the pads must not be elongated underneath the module.
no metal for
31mm from edge
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Underneath the radio module the top layer of the motherboard should be kept free
from tracks and vias due to the fact that the module’s bottom side is only covered with
solder resist with no specified isolation properties, and the vias are not covered at all.
15.3 General advice for schematic and layout
For less experienced RF users it is advisable to closely copy the relating evaluation board with
respect to schematic and layout, as it is a proven design. The layout should be conducted with
particular care, because even small deficiencies could affect the radio performance and its
range or even the conformity.
The following general advice should be taken into consideration:
A clean power supply is strongly recommended. Interference, especially oscillation can
severely restrain range and conformity.
Variations in voltage should be avoided.
LDOs, properly designed in, usually deliver a proper regulated voltage.
Blocking capacitors and a ferrite bead in the power supply line can be included to filter
and smoothen the supply voltage when necessary.
No fixed values can be recommended, as these depend on the circumstances of the
application (main power source, interferences etc.).
Elements for ESD protection should be placed on all Pins that are accessible from the
outside and should be placed close to the accessible area. For example, the RF-Pin is
accessible when using an external antenna and should be protected.
ESD protection for the antenna connection must be chosen such as to have a minimum
effect on the RF signal. For example, a protection diode with low capacitance such as
the LXES15AAA1-100 or a 68 nH air-core coil connecting the RF-line to ground give
good results.
Placeholders for optional antenna matching or additional filtering are recommended.
Again, no fixed values can be recommended, as they depend on the influencing
circumstances of the application (antenna, interferences etc.).
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Figure 1: Layout
To avoid the risk of short circuits and interference there should be no routing underneath
the module on the top layer of the printed circuit board.
On the second layer, a ground plane is recommended, to provide good grounding and
shielding to any following layers and application environment.
In case of integrated antennas it is required to have areas free from ground. This area
should be copied from the evaluation board.
The area with the integrated antenna must overlap with the carrier board and should not
protrude, as it is matched to be placed directly on top of a PCB.
Modules with integrated antennas should be placed with the antenna at the edge of the
main board. It should not be placed in the middle of the main board or far away from the
edge. This is to avoid tracks being placed beside the antenna.
Filter and blocking capacitors should be placed directly in the tracks without stubs, to
achieve the best effect.
Antenna matching elements should be placed close to the antenna/connector and
blocking capacitors close to the module.
Ground connections for the module and the capacitors should be kept as short as
possible and with at least one separate through hole connection to the ground layer.
ESD protection elements should be placed as close as possible to the exposed areas.
Figure 2: Placement of the module
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15.4 Antenna connection
The antenna track has to be designed as a 50 Ohm feed line.
Figure 5 Dimensioning the antenna feed line as micro strip
The width W for a micro strip can be calculated using the following equation:
met
T
e
H
Wr
87
41.150
98.5
25.1
Equation 1 Parameters of the antenna feeding line
Example: a FR4 material with r = 4.3, a height H = 1000 µm and a copper thickness of Tmet= 18
µm will lead to a trace width of W ~ 1.9 mm. To ease the calculation of the micro strip line (or
e.g. a coplanar) many calculators can be found in the internet.
As rule of thumb a distance of about 3 x W should be observed between the micro strip
and other traces / ground.
The micro strip refers to ground, therefore there has to be the ground plane underneath
the trace.
Keep the feeding line as short as possible.
15.5 Antenna solutions
There exist several kinds of antennas, which are optimized for different needs. Chip antennas
are optimized for minimal size requirements but at the expense of range, PCB antennas are
optimized for minimal costs, and are generally a compromise between size and range. Both
usually fit inside a housing. Range optimization in general is at the expense of space. Antennas
that are bigger in size, so that they would probably not fit in a small housing, are usually
equipped with a RF connector. A benefit of this connector may be to use it to lead the RF signal
through a metal plate (e.g. metal housing, cabinet).
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As a rule of thumb a minimum distance of λ /10 (3.5 cm @ 868 MHz, 1.2 cm @ 2.44 GHz) from
the antenna to any other metal should be kept. Metal placed further away will not directly
influence the behaviour of the antenna, but will never the less produce shadowing.
Keep the antenna away from large metal objects as far as possible to avoid
electromagnetic field blocking.
In the following chapters, some special types of antenna are described.
15.5.1 Lambda/4 radiator
An effective antenna is a λ/4 radiator. The simplest realization is an 8.6 cm long piece of wire for
868 MHz, respectively a 3.1 cm long piece of wire for 2.44 GHz. This radiator needs a ground
plane at its feeding point. Ideally, it is placed vertically in the middle of the ground plane. As this
is often not possible because of space requirements, a suitable compromise is to bend the wire
away from the PCB respective to the ground plane. The λ/4 radiator has approximately 40 Ohm
input impedance, therefore matching is not required.
15.5.2 Chip antenna
There are many chip antennas from various manufacturers. The benefit of a chip antenna is
obviously the minimal space required and reasonable costs. However, this is often at the
expense of range. For the chip antennas, reference designs should be followed as closely as
possible, because only in this constellation can the stated performance be achieved.
15.5.3 PCB antenna
PCB antenna designs can be very different. The special attention can be on the miniaturization
or on the performance. The benefits of the PCB antenna are their minimal (if PCB space is
available) costs, however the evaluation of a PCB antenna holds more risk of failure than the
use of a finished antenna. Most PCB antenna designs are a compromise of range and space
between chip antennas and connector antennas.
15.5.4 Antennas provided by AMBER
15.5.4.1 AMB1926
The AMB1926 is a 2.4 GHz antenna with SMA connection and swivel base.
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16 Manufacturing information
The assembly contains moisture sensitive devices of the MSL classification 3. Only the
dry packed Tape & Reel devices are suitable for the immediate processing in a reflow
process.
Further information concerning the handling of moisture sensitive devices, (e.g. drying)
can be obtained from the IPC/ JEDEC J-STD-033.
Recommendations for the temperature profile for the soldering furnace cannot be made,
as it depends on the substrate board, the number and characteristics of the
components, and the soldering paste used (consult your EMS). Jedec J-STD-020 should
be considered.
Figure 6 shows a soldering curve that had been used for a 31 cm2 carrier board for
single-side assembly.
Figure 6 Example of a temperature profile –
Caution: Must be adjusted to the characteristics of the carrier board!
To ensure the mechanical stability of the modules it is recommended to solder all the
pads of the module to the base board, even if they are not used for the application.
Caution! ESD sensitive device.
Precaution should be taken when handling the device in order to prevent
permanent damage.
MSL 3
Caution! This assembly contains moisture sensitive components.
Precaution should be taken when processing the device according to
IPC/JEDEC J-STD-033.
Since the module itself is not fused the voltage supply shall be coming from a limited
power source according to clause 2.5 of EN 60950-1.
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17 Firmware history
Version
Date
Description
1.0.0
02/15
First release
2.0.0
09/15
Better transmission reliability, thus payload size
decreased to 26 bytes
New command CMD_BOOTLOADER_REQ
Firmware version 2.0.0 is not RF-compatible to 1.0.x
3.0.0
10/15
New command interface, incompatible to firmware before
3.0.0
Introduced the fragmentation mode to send larger
packets
CFG Flags updated
Broadcast address changed from 0x01 to 0xFF
3.1.1
11/16
New power levels (default is still maximum)
Bugfix in length field of CMD_DATAEX_IND
3.2.2
1/17
Added the user setting UART_Baudrate that determines
the UART baud rate of the module
3.3.0
3/17
Added higher RF data rates
Improved internal timings resulting in faster data
processing
Reduced sleep current to about 1µA
3.5.0
9/17
Ported to default firmware design scheme
Optimisations in RAM requirements and timings
Minor bug fixes
Added temperature calibration for the radio tx power and
radio frequency
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18 Regulatory compliance information
18.1 Important notice
The use of RF frequencies is limited by national regulations. The AMB2220 has been designed
to comply with the Radio Equipment Directive 2014/53/EU of the European Union (EU).
The AMB2220 can be operated without notification and free of charge in the area of the
European Union. However, according to the RED, restrictions (e.g. in terms of duty cycle or
maximum allowed RF power) may apply.
Conformity assessment of the final product
The AMB2220 is a subassembly. It is designed to be embedded into other products (products
incorporating the AMB2220 are henceforward referred to as "final products").
It is the responsibility of the manufacturer of the final product to ensure that the final product is
in compliance with the essential requirements of the European Union's Radio Equipment
Directive.
The conformity assessment of the subassembly AMB2220 carried out by Würth Elektronik
eiSos does not replace the required conformity assessment of the final product in accordance to
the RED.
Exemption clause
Relevant regulation requirements are subject to change. Würth Elektronik eiSos does not
guarantee the accuracy of the before mentioned information. Directives, technical standards,
procedural descriptions and the like may be interpreted differently by the national authorities.
Equally, the national laws and restrictions may vary with the country. In case of doubt or
uncertainty, we recommend that you consult with the authorities or official certification
organizations of the relevant countries. Würth Elektronik eiSos is exempt from any
responsibilities or liabilities related to regulatory compliance.
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18.2 Declaration of Conformity
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18.3 FCC Compliance statement
FCC ID: R7TAMB2220
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and
(2) this device must accept any interference received, including interference that may cause
undesired operation.
(FCC 15.19)
Modifications (FCC 15.21)
Caution: Changes or modifications for this equipment not expressly approved by Würth
Elektronik eiSos may void the FCC authorization to operate this equipment.
18.4 IC Compliance statement
Certification Number: 5136A-AMB2220
This device complies with Industry Canada licence-exempt RSS standard(s). Operation is
subject to the following two conditions: (1) this device may not cause harmful interference, and
(2) this device must accept any interference received, including interference that may cause
undesired operation.
Le présent appareil est conforme aux CNR d'Industrie Canada applicables aux appareils radio
exempts de licence. L'exploitation est autorisée aux deux conditions suivantes : (1) l'appareil ne
doit pas produire de brouillage, et (2) l'utilisateur de l'appareil doit accepter tout brouillage
radioélectrique subi, même si le brouillage est susceptible d'en compromettre le
fonctionnement.
18.5 FCC and IC Requirements to OEM integrators
This module has been granted modular approval. OEM integrators for host products may use
the module in their final products without additional FCC / IC (Industry Canada) certification if
they meet the following conditions. Otherwise, additional FCC / IC approvals must be obtained.
The host product with the module installed must be evaluated for simultaneous transmission
requirements.
The users manual for the host product must clearly indicate the operating requirements and
conditions that must be observed to ensure compliance with current FCC / IC RF exposure
guidelines.
To comply with FCC / IC regulations limiting both maximum RF output power and human
exposure to RF radiation, the maximum antenna gain including cable loss in a mobile-only
exposure condition must not exceed 2dBi.
A label must be affixed to the outside of the host product with the following statements:
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AMB2220_MA_3_12 Page 47 of 48 Date: 05/2018
This device contains FCCID: R7TAMB2220
This equipment contains equipment certified under ICID: 5136A-AMB2220
The final host / module combination may also need to be evaluated against the FCC Part 15B
criteria for unintentional radiators in order to be properly authorized for operation as a Part 15
digital device.
If the final host / module combination is intended for use as a portable device (see
classifications below) the host manufacturer is responsible for separate approvals for the SAR
requirements from FCC Part 2.1093 and RSS-102.
OEM Requirements:
The OEM must ensure that the following conditions are met.
End users of products, which contain the module, must not have the ability to alter the
firmware that governs the operation of the module. The agency grant is valid only when the
module is incorporated into a final product by OEM integrators.
The end-user must not be provided with instructions to remove, adjust or install the module.
The Original Equipment Manufacturer (OEM) must ensure that FCC labeling requirements
are met. This includes a clearly visible label on the outside of the final product. Attaching a
label to a removable portion of the final product, such as a battery cover, is not permitted.
The label must include the following text:
Contains FCC ID: R7TAMB2220
The enclosed device complies with Part 15 of the FCC Rules. Operation is subject to
the following two conditions: (i.) this device may not cause harmful interference and
(ii.) this device must accept any interference received, including interference that may cause
undesired operation.
When the device is so small or for such use that it is not practicable to place the statement
above on it, the information required by this paragraph shall be placed in a prominent location in
the instruction manual or pamphlet supplied to the user or, alternatively, shall be placed on the
container in which the device is marketed. However, the FCC identifier or the unique identifier,
as appropriate, must be displayed on the device.
The user manual for the end product must also contain the text given above.
Changes or modifications not expressly approved could void the user's authority to operate
the equipment.
The OEM must ensure that timing requirements according to 47 CFR 15.231(a-c) are met.
The OEM must sign the OEM Modular Approval Agreement with xxxxx
The module must be used with only the following approved antenna(s).
18.6 AMB2220 & AMB2220-1
The module variants HVIN AMB2220 and AMB2220-1 collected in the PMN AMB2220 are
identical in enclosure, appearance, PCB design and bands/technologies.
The only difference is, that in AMB2220 an integrated Chip Antenna is used and for the
AMB2220-1 an external λ/4 Antenna is used.
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19 Important information
19.1 Exclusion of liability
Würth Elektronik eiSos presumes that the information in this document is correct at the time of
publication. However, Würth Elektronik eiSos reserves the right to modify technical
specifications or functions of its products or discontinue the production of these products or the
support of one of these products without any written announcement or notification to customers.
The customer must make sure that the information used is valid. Würth Elektronik eiSos does
not assume any liability for the use of its products. Würth Elektronik eiSos does not grant
licenses for its patent rights or for any other of its intellectual property rights or third-party rights.
Customers bear responsibility for compliance of systems or units in which Würth Elektronik
eiSos products are integrated with applicable legal regulations.
19.2 Trademarks
AMBER wireless® is a registered trademark of Würth Elektronik eiSos.
All other trademarks, registered trademarks, and product names are the exclusive property of
the respective owners.
19.3 Usage restriction
Würth Elektronik eiSos products are not approved for use in life-supporting or life-sustaining
systems or units or other systems whose malfunction could result in serious bodily injury to the
user. Moreover, Würth Elektronik eiSos products are not approved for use as key components
of any life-supporting or life-sustaining system or unit whose malfunction could result in the
failure of the life-supporting system or unit or could affect its safety or effectiveness. Würth
Elektronik eiSos customers who use these products in such applications or sell them for such
usage act at their own risk and must relieve Würth Elektronik eiSos from all damages that may
result from the sale for unsuitable purposes or unsuitable usage.
By using Würth Elektronik eiSos products, the user agrees to these terms and conditions.
Copyright © 2017, Würth Elektronik eiSos. All rights reserved.
Würth Elektronik eiSos
Phone +49.651.993.550
Internet www.we-online.com/wireless-connectivity