Silicon Laboratories Finland BT121 BT121 Bluetooth Smart Ready Module User Manual Product Data Sheet

Silicon Laboratories Finland Oy BT121 Bluetooth Smart Ready Module Product Data Sheet

Datasheet

BT121 BLUETOOTH SMART READY MODULE DATA SHEET Tuesday, 09 June 2015 Document Version: 1.41
Bluegiga – A Silicon Labs Company Copyright © Silicon Labs All rights reserved. Silicon Labs assumes no liability or responsibility for any errors, mistakes or inaccuracies in content. Silicon Labs reserves the right to change products or specifications without notice, and does not make any commitment to update the information herein. Silicon Labs’ products are not authorized for use as critical components in life support devices or systems. BGScript™ is a trademark of Silicon Labs. The Bluetooth® word mark and logos are registered trademarks owned by the Bluetooth® SIG, Inc. USA. All other trademarks and trade names listed herein belong to their respective owners. Information is subject to change without notice.
Bluegiga – A Silicon Labs Company VERSION HISTORY Date Edited Comment 1.0 First release of document 1.1 Minor updates 1.2 Minor updates 1.3 Power consumption measurements 1.4 Revised power consumption measurements 1.41 FCC statement
Bluegiga – A Silicon Labs Company 4 TABLE OF CONTENTS BT121 overview 6 1.1 Key Features 6 1.2 Typical applications 7 1.3 Block diagram 7 Design guidelines 8 2.1 PCB layout recommendations 8 2.2 Power supply recommendations 8 2.3 Software application related options 8 2.4 Firmware updating related recommendations 8 Pin-out description 10 3.1 Power, ground, reset, RF and boot loader pins 10 3.2 GPIO pins 11 Power control 12 4.1 Power supply requirements 12 4.2 Power saving functionality 12 4.3 Reset 13 4.4 Recovery mode 14 4.5 Clock signals 14 Interfaces 15 5.1 GPIO 15 5.2 UART 16 5.3 I2C 16 5.4 SPI 16 5.5 ADC 16 5.6 DAC 16 5.7 Real-time clock 16 5.8 Microcontroller programming interface 16 Antenna 17 6.1 Effect on antenna matching of a plastic sheet placed near the antenna 18 6.2 Effect on antenna matching of a metal sheet placed under the antenna 19 6.3 Effect on antenna matching of a metal sheet placed against the end of the module 20 6.4 Measured antenna efficiency 21 6.5 Measured 2D radiation patterns 22 6.6 Measured 3D radiation patterns 24 Bluetooth Stack Software 25 Host interface 26
Bluegiga – A Silicon Labs Company 5 8.1 UART 26 Connection examples 27 9.1 Connecting an external host using the UART interface 27 9.2 Connecting an external device using SPI interface 28 9.3 Connecting an external device using I2C interface 29 Electrical characteristics 30 10.1 Absolute maximum ratings 30 10.2 Recommended operating conditions 30 10.3 Logic signal characteristics 31 RF Characteristics 33 11.1 Supported frequencies and channels 35 11.2 Typical receiver sensitivity 35 11.3 Transmitter output power 35 11.4 Carrier frequency accuracy 35 Physical dimensions 36 Soldering recommendations 38 13.1 Soldering profile example 39 Tape and reel packaging 40 14.1 Reel material and dimensions 40 14.2 Tape material and dimensions 40 14.3 Tape and reel box dimensions 41 14.4 Module orientation in tape 41 Certifications 42 15.1 CE 42 15.2 FCC and IC 42 Ordering information 44 Contact Information 45
Bluegiga – A Silicon Labs Company 6 BT121 overview BT121 is a Bluetooth Smart Ready module targeted for applications that require both Bluetooth Smart and Classic connectivity. It can connect to legacy devices that only support Bluetooth SPP or Apple® iAP2 profiles as well to devices that support Bluetooth Smart. BT121 integrates a high performance Bluetooth radio, a low-power ARM Cortex micro-controller and a Bluegiga Bluetooth Smart Ready stack software marking it extremely easy-to-use as no RF or Bluetooth software development is needed. BT121 can be used as a modem together with a separate host MCU, but applications can also be embedded into the built-in ARM® Cortex® MCU with the Bluegiga BGScriptTM scripting language. 1.1 Key Features Bluetooth features  Bluetooth 4.1 Smart Ready compliant  Master and slave modes  Up to 6 x BR/EDR connections  Up to 7 x BLE connections  1 x BR/EDR + 7 x BLE connections simultaneously Radio features  Integrated antenna  TX Power o +12 dBm with Bluetooth BR/EDR o +10 dBm with Bluetooth LE  RX Sensitivity o -96 dBm  200-400 meter LoS range Software features  Integrated Bluetooth Smart Ready Stack  SPP, iAP2, GATT over BR Bluetooth profiles  Any GATT based Bluetooth Smart profile  1000 kbps throughput over SPP  150 kbps throughput over iAP2  100 kbps throughput over BLE  BGAPITM serial protocol API over UART for modem usage  BGLIBTM host API/library which implements BGAPI serial protocol  BGScriptTM scripting language for standalone usage  Profile ToolkitTM for creating GATT based services Hardware interfaces  UART host interface  2 x SPI, UART and 2 x I2C peripheral interfaces  Up to 22 x GPIO with interrupts  4 x 12-bit ADC and 2 x 12-bit DAC*  Internal temperature sensor*  Internal battery voltage measurement option*  Clock generator*  RTC with calendar* Microcontroller  ARM Cortex M0  48 Mhz  16kB RAM  128kB flash Electrical characteristics  Supply voltage: 2.2V to 3.6V  Supply voltage: 2.4V to 3.6V when using ADC Environmental and regulatory  Temperature range: -40C to +85C  Bluetooth, CE, FCC and IC, Japan and South-Korea qualified* Dimensions:  W x L x H: 11.0 mm x 13.9 mm x 2.2 mm *) Feature not implemented on engineering samples and engineering samples are not qualified
Bluegiga – A Silicon Labs Company 7 1.2 Typical applications BT121 can be used in a wide variety of applications such as health and fitness, PoS (point-of-sales), M2M connectivity, automotive aftermarket, industrial and home automation gateways and others. 1.3 Block diagram The block diagram for Bluegiga Bluetooth Smart Ready module BT121 is shown in below. Figure 1 BT121 Bluetooth Smart Ready module block diagram
Bluegiga – A Silicon Labs Company 8 Design guidelines Certain hardware related design guidelines should always be followed when developing applications based on the BT121 module. 2.1 PCB layout recommendations  All ground pads should be connected to a ground plane.  The antenna layout should follow the example shown in Figure 2 below and avoid the designs shown as crossed over.  BT121 requires minimal free space around the module and only the white area marked in the PCB picture series presented in Figure 2 below needs to be free of copper and components. Figure 2 PCB layout recommendations for BT121 application boards 2.2 Power supply recommendations The regulator used must be capable of supplying a peak current of 150 mA and the regulator must be of a type stable with ceramic capacitors. 2.3 Software application related options BT121 can be used either as a stand-alone solution by using the Bluegiga BGScript™ scripting language or alternatively if the application software size or other factors require together with an external host processor by using Bluegiga BGAPI™ commands. The decision on which approach to use is most often dictated by the limits set by the internal memory of the BT121 module. 2.4 Firmware updating related recommendations To enable firmware updating an external UART interface connection as shown in Figure 3 on the next page is mandatory. BT121 firmware can be updated through the UART interface by holding the host MCU in reset state which typically will free the UART lines to be used by the update interface.
Bluegiga – A Silicon Labs Company 9 Figure 3 BT121 firmware update via UART connection example
Bluegiga – A Silicon Labs Company 10 Pin-out description This section contains a description of the BT121 pin-out. Each pin may have one or more functions which are all listed in tables. The pin-out is shown in Figure 4 below. Figure 4 BT121 pin-out (top view) 3.1 Power, ground, reset, RF and boot loader pins Power supply, ground, reset signal, RF antenna input/output and boot loader related pins are listed in Table 1 below. Pin / Pad Function Description 30,34 VDD Module power supply input pins. 1, 2, 3, 13, 21, 31, 32, 33, 41 GND Ground pin. These are all connected together internally but they should all be individually connected directly to a solid ground plane with vias in close proximity to the pins. This requirement concerns especially the antenna connections. 22,40 RESET Module reset signal pins. Pulling RESET low will reset the internal processor of the module. These connections have an internal pull-up and can be left floating if not needed. 23,35 BOOT0 Boot mode pin of the microcontroller internal boot loader. This connection has an internal pull-down and should be left floating or pulled low in normal operation. If the Bluegiga DFU is overwritten or disabled, pulling BOOT0 high at reset will allow DFU to be rewritten through the UART (serial port interface). Table 1 Power, ground, reset, RF and boot loader pins
Bluegiga – A Silicon Labs Company 11 3.2 GPIO pins General purpose I/O pins and their functions are listed below. PERIPHERAL FUNCTION GPIO NAME PA7 PA6 PA5 PA4 PB3 PB4 PB5 PB6 PB7 PB8 PB9 PB10 PB12 PB13 PB14 PB15 PA13 PA14 RTS PA12 CTS PA11 RX PA10 TX PA9 PIN NUMBER 4 5 6 7 8 9 10 11 12 14 15 16 17 18 19 20 24 25 26 37 27 36 28 38 29 39 DEFAULT FUNCTION ** dc dc dc dc dc dc dc dc dc dc dc dc dc dc dc dc dc dc RTS CTS RX TX 5V TOLERANT N N N N Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y UART *** RTS CTS RX TX SPI 1 Alt.1 MOSI MISO SCK NSS* Alt.2 NSS* SCK MISO MOSI SPI 2 Alt.1 NSS* SCK MISO MOSI Alt.2 NSS* SCK MISO MOSI I2C 1 Alt.1 SCL SDA Alt.2 SCL SDA I2C 2 Alt.1 Alt.2 SCL SDA DAC output AO2 AO1 ADC input AIN7 AIN6 AIN5 AIN4 Interrupt channel 7 6 5 4 3 4 5 6 7 8 9 10 12 13 14 15 13 14 12 11 10 9 Table 2 General purpose I/O pins and their functions * NSS signal is optional, see SPI description (Section 5.4 ) GPIO pins 36, 37, 38 and 39 ** Default pin functions on production firmware / dc = disconnected, no need to pull up or down Reserved for production testing *** UART can be used as a BGAPI™ host interface and DFU firmware updates Must be left unconnected If the pins are set as GPIO rather than UART signals the DFU cannot work, see UART (Section 5.2 ) and recovery mode (Section 4.4 ) I2C 2 cannot be used in Alt. 2 configuration
Bluegiga – A Silicon Labs Company 12 Power control 4.1 Power supply requirements BT121 is powered by a single power supply input (VDD). Nominal input voltage is 3.3 VDC and input voltage range 2.2 V to 3.6 V. If the module’s internal ADC and/or DAC functions are used minimum allowed power supply voltage is 2.4V. The VDD supply should be capable of supplying a peak current of at least 150 mA even though the average current consumption of BT121 will be much less than that. External high frequency bypass capacitors are not needed because the module contains the necessary power supply filtering capacitors. Careful design of the layout and proper component selection are necessary to prevent switching noise from appearing on the supply line. Such disturbances can be caused by on-board charge pump converters (e.g. RS232 level shifters). Charge pump based converters tend to have strong switching spikes which are difficult to filter out and may degrade RF performance. A ferrite chip can be added in series with the supply line close to the module supply pin to reduce RF interference through the supply line. There is a total of about 1.5 µF of ceramic capacitors on the VDD line inside the module. When using low drop linear regulators to generate a regulated supply voltage for the VDD line, the stability of the regulator with the low ESR provided by these capacitors should be checked. Many linear regulators and some switched mode ones too are not stable when used with ceramic output capacitors. The regulator datasheets usually have recommendations for output capacitor ESR range or they contain a stability curve to help select components properly. A regulator designated as “stable with ceramic capacitors” is recommended. 4.2 Power saving functionality BT121 contains two configurable power saving modes. The internal RTC (Real Time Clock) is usually kept always running to avoid the long wake-up time associated with the internal 32 kHz crystal oscillator. The RTC is always available to wake up the module. 4.2.1 Power mode 1 Power mode 1 is a shallow sleep state with all clocks and peripherals running but with the processor core stopped. It is used automatically and has no impact on module performance and does not require special considerations in user applications. See Table 3 on next page. 4.2.2 Power mode 2 Power mode 2 is a deep sleep state, in which most peripheral devices and system clocks are powered down. The UART interfaces cannot operate without clocks, and instant communications with the host are not possible. A separate wake-up command on the host UART or a PIO interrupt can be used to wake up the module, or an RTC event. The radio can also cause a wake-up event. There is a short wake-up delay due to the time required for the internal clocks to stabilize and because of this the module processor is not instantly ready to receive data. See Table 3 on next page.
Bluegiga – A Silicon Labs Company 13 Power mode CPU clocks CPU core Radio Wakeup delay UART Current consumption * Active ON Running On - Active 10 - 20 mA Power mode 1 ON Stopped On < 7μs Active 4 - 10 mA Power mode 2 OFF Powered off On < 70 μs Off 50 - 100 μA Table 3 Power modes with corresponding wakeup delays and current consumption * Current consumption with radio inactive The logic flow of the power saving modes in relation to each other is shown in Figure 5 below. It is to be noted that the processor will not lose RAM contents regardless of the power mode used. Figure 5 Power modes in relation to each other and to active mode 4.3 Reset BT121 can be reset by several methods: by pulling the RESET pin low, by the internal system power-up reset functionality or by the internal watchdog timer. The RESET pin is internally connected to a pull-up resistor with a resistance of approximately 40 kohm. The RESET pin should be connected to a push-button, header or test point to enable the use of the system recovery mode.
Bluegiga – A Silicon Labs Company 14 4.4 Recovery mode Pulling the BOOT0 pin high at reset sets the BT121 module’s internal microcontroller into a recovery mode, which allows the Bluegiga DFU to be rewritten to the module using the DumoGUI software. The BOOT0 pin should be connected to a header or test point to enable DFU recovery. The pin is internally connected to a 10 kohm pull-down resistor. 4.5 Clock signals BT121 generates all the required clock signals internally. The clocks used by the internal microcontroller and external peripherals are synchronized to an internal 32.768 kHz crystal connected to the internal RTC. The micro power RTC is always kept running when the module is supplied with power. It will take approximately two seconds for the RTC oscillator to stabilize after power is connected. To avoid this delay it is recommended that the power supply feed to the BT121 is not switched off but instead the module can be set into the lowest power mode providing the smallest current consumption.
Bluegiga – A Silicon Labs Company 15 Interfaces 5.1 GPIO BT121 contains a number of pins which can be configured to operate as general purpose digital I/O’s, analog inputs or outputs or to be used in combination with various built-in functions. The module contains I2C, SPI, UART, touch pad sensing and various timer functions. Most of the pins are 5V tolerant. All GPIO pins can drive currents of up to +/- 8 mA (up to 20mA with relaxed voltage specifications). 5.1.1 GPIO interrupts Any GPIO signal can be assigned an interrupt function. However, the module microcontroller has a limited number of interrupt channels available for GPIO’s. The microcontroller has two separate GPIO ports, with the external signals divided between the two. An interrupt can be assigned to a specific port signal number from either port, but not for the same number on both ports simultaneously. The principle of GPIO interrupt multiplexing on the Bluegiga Bluetooth Smart Ready module BT121 is shown in Figure 6 below. Figure 6 GPIO interrupt multiplexing scheme
Bluegiga – A Silicon Labs Company 16 5.2 UART There is one UART port available on the BT121. By default it is used for BGAPI™ host interface but with BGScript™ it can be used as an application UART. The UART supports all standard baud rates up to 4 Mbps. RTS/CTS handshake scheme is supported and recommended for every application for reliable data transfer. 5.3 I2C BT121 has up to two I2C ports available. Both support standard mode up to 100 kbps, fast modes up to 400 kbps and Fast Mode Plus with improved drive capability and clock stretching up to 1 Mbps. 5.4 SPI BT121 has up to two SPI ports available. Both can be configured for frame sizes from 4 to 16 bits and clock frequencies up to 18 MHz. Both ports provide internal CRC calculation. An optional slave select signal (NSS) is provided for hardware assisted data strobing in applications requiring high bus throughputs. 5.5 ADC BT121 contains a 4-channel 12-bit ADC with multiple external input sources as well as an internal battery measurement and temperature measurement possibility. ADC input voltage range is 0 to VDD. 5.5.1 Accessory functions of the ADC In addition to the external ADC inputs an internal temperature sensor or internal supply voltage divider can be selected as the input to ADC. Power supply range when using internal ADC functions is 2.4 to 3.6 VDC. 5.6 DAC BT121 contains a 2-channel 12-bit DAC, with two independent outputs. DAC output voltage range is 0 to VDD. Power supply range when using internal DAC functions is 2.4 to 3.6 VDC. 5.7 Real-time clock BT121 contains a real-time clock (RTC) with full calendar support and sub-second resolution. The RTC can be used for periodic or specifically programmed wakeups. The RTC is clocked by an internal crystal oscillator which is always on as long as power is supplied to the module. 5.8 Microcontroller programming interface The preferred method of programming the BT121 is by using the Bluegiga DFU through the UART host interface. A problem may occur if the DFU is disabled by disabling the UART or if the DFU is overwritten accidentally. Then the DFU would need to be re-uploaded. The two methods of firmware upload are through the SWDIO/SWCLK interface (PA13 and PA14) using an ARM serial debug adapter, or by forcing the BOOT0 signal high and by resetting the module to make it boot into a recovery mode. Then the BGTool software can be used to recover the DFU through the UART interface.
Bluegiga – A Silicon Labs Company 17 Antenna The internal chip antenna on the BT121 uses the application board ground plane as part of the antenna, and requires at least 20 mm of ground plane on both sides of the module to radiate with optimal efficiency. BT121 must be placed on the application board edge, preferably roughly in the middle of the board edge. The ground plane can be internal to the application PCB, allowing components to be placed on both sides of the module and on both sides of the application board. The module ground pads in the antenna end should be connected to the main ground plane layer with vias in immediate proximity of the pins. Thermal reliefs on the ground pins have a negligible effect on antenna performance. Typical antenna matching curves are shown in Figure 7 below. Figure 7 Typical antenna matching The antenna used on the BT121 is quite robust with regard to adverse effects of close-by metallic materials. The PCB thickness will not affect the antenna operation significantly. The application board can be installed with the PCB bottom side and the antenna edge directly against a plastic casing without adverse effects. On the module top side, there should be at least 3 mm of clearance to the nearest object. The antenna requires a 7.5 x 3.4 mm sized copper clearance in all layers, with no components or traces on the opposite side of the PCB from the antenna. Sufficient metal clearance is mandatory because the antenna will not function at all without a sufficient opening in the ground plane. Any metal in close proximity of the antenna will prevent the antenna from radiating freely. It is recommended not to place any metal or other conductive objects closer than 10 mm to the antenna except in the directions of the application board ground planes. A board cutout is not required for the antenna. In fact, a cutout would cause the antenna to be detuned which in turn will degrade range significantly. The module is also not to be placed in a cut-out recess on the board edge or in the middle of the board which has a central cutout. On the following pages are examples on how plastic or metal sheets in several different orientations and distances to the antenna effect antenna matching. Violet curve: with thermal reliefs Blue curve: without thermal reliefs
Bluegiga – A Silicon Labs Company 18 6.1 Effect on antenna matching of a plastic sheet placed near the antenna As an example on how a plastic sheet placed in the vicinity of the module and/or antenna effect the antenna matching we can examine Figure 8 below. Figure 8 Proximity effect of a 3 mm plastic sheet on antenna matching with different placements Blue curve Plastic sheet under antenna touching PCB Violet curve Plastic sheet against antenna at module end Yellow curve Plastic sheets under antenna touching PCB and against antenna at module end
Bluegiga – A Silicon Labs Company 19 6.2 Effect on antenna matching of a metal sheet placed under the antenna As an example on how a metal sheet placed in the vicinity of the module and/or antenna effect the antenna matching we can examine Figure 9 below. Figure 9 Effect of a metal sheet placed under the antenna on antenna matching Violet curve Metal sheet under antenna touching PCB Blue curve Same as on the left but distance is 1 mm
Bluegiga – A Silicon Labs Company 20 6.3 Effect on antenna matching of a metal sheet placed against the end of the module As an example on how a metal sheet placed in the vicinity of the module and/or antenna effect the antenna matching we can examine Figure 10 below. Figure 10 Effect of a metal sheet placed under the antenna on antenna matching Violet curve Metal sheet against end of module end Violet curve Metal sheet at module end 5 mm distance
Bluegiga – A Silicon Labs Company 21 6.4 Measured antenna efficiency The measured antenna efficiency as a function of frequency is shown in Figure 11 below. Figure 11 Antenna efficiency related to frequency
Bluegiga – A Silicon Labs Company 22 6.5 Measured 2D radiation patterns Typical radiation patters of the BT121 module shown as 2D plots are shown below in Figure 12 (view from module side), Figure 13 (view from antenna end) and on the following page in Figure 14 (view from above module). Figure 12 Typical 2D radiation pattern for BT121 with view from module side Figure 13 Typical 2D radiation pattern for BT121 with view from antenna end side
Bluegiga – A Silicon Labs Company 23 Figure 14 Typical 2D radiation pattern for BT121 with view from above module
Bluegiga – A Silicon Labs Company 24 6.6 Measured 3D radiation patterns Typical radiation patters of the BT121 module shown as 3D plots are shown below. Figure 15 represents a radiation pattern from module end side opposite to antenna and Figure 16 from above the module. Figure 15 Typical 3D radiation pattern for BT121 with view from module end opposite to antenna Figure 16 Typical 3D radiation pattern for BT121 with view from above the module
Bluegiga – A Silicon Labs Company 25 Bluetooth Stack Software Bluegiga's Bluetooth Smart Ready Software is a complete Bluetooth Smart Ready software stack for BT121 Bluetooth Smart Ready module. The software implements a full Bluetooth BR/EDR and LE compatible Bluetooth Stack and L2CAP, RFCOMM, SMP and ATT protocols as well as Bluetooth SPP, Apple iAP2, GATT over BT profiles and any GATT based Bluetooth Smart profile. The Bluetooth Smart Ready Software also is supported by a complete SDK for developing Bluetooth Smart Ready applications using either an external host or BGAPITM serial protocol over UART or fully standalone applications based on a simple scripting language called BGScriptTM. Several profiles and software project examples are offered as part of the Bluetooth Smart Ready SDK to help expedite the development of Bluetooth Smart Ready compatible end-user products. The main parts of the Bluegiga Bluetooth Smart Ready software stack are shown below. Figure 17 Bluegiga Bluetooth Smart Ready software stack To learn more about the Bluetooth Smart Ready software stack, the SDK and the APIs please read Bluetooth Smart Ready Software Getting Started Guide.
Bluegiga – A Silicon Labs Company 26 Host interface 8.1 UART For applications where an external host such as MCU is used BT121 can be controlled over the UART interface using the BGAPITM serial protocol. For reliable communications can data transfer the hardware flow control RTS/CTS signals must be used in the UART interface. It is also recommended that the accuracy of the clock of the controlling host should be 1% or better for the UART signaling to work reliably with speeds exceeding 115200 kbps (maximum baud rate is 4 Mbps). Default UART settings are listed below: Parameter Default setting UART baud rate 115200 RTS/CTS flow control Enabled Data bits 8 Parity None Stop bits 1 Table 4 BT121 UART interface default settings
Bluegiga – A Silicon Labs Company 27 Connection examples The following sections show how to connect a Bluegiga Bluetooth Smart Ready module with various external devices using the UART, SPI and I2C interface. 9.1 Connecting an external host using the UART interface The connection to an external host is done using the UART interface of the module. This interface is also used for module reprogramming using the DFU method and thus an optional connector should be provided on the application PCB to allow reprogramming if needed. A typical solution then is to hold the host in reset state which will keep the UART pins of the host floating, allowing the interface to be used for programming the module by using e.g. a PC and suitable software. See Figure 18 . 40GNDGNDGNDPA7PA6PA5PA4PB3PB4PB5PB6PB7GNDPA11GNDGNDGNDVDDPA9PA10PA12PA14PA13BOOT0RESETGNDVDDPA10RESETBOOT0PA12PA9GNDPB8PB9PB10PB12PB13PB141234567891011121314 15 16 17 18 19PB1520RXRTS33323130292826252423222134363841353739BT121RESERVED FOR PRODUCTION PROGRAMMINGTXTOP VIEW27PA11 CTSBT121UART3V3EXTERNAL HOSTMICROPROCESSOR3V3RXTXRTSCTSVDDVSSHOST UARTGND NC RX TX RTS CTS RST VDDRESET3V3OPTIONAL CONNECTOR ON APPLICATION PCB ALLOWS CONTROL AND REFLASH OF MODULE FOR EXAMPLE FROM A PC Figure 18 Connecting an external host with BT121 using UART
Bluegiga – A Silicon Labs Company 28 9.2 Connecting an external device using SPI interface Bluegiga Bluetooth Smart Ready module BT121 contains two physical SPI peripherals (SPI 1 and SPI2) each with alternative configurations (Alt 1 and Alt 2). All of the four optional configurations can be used to connect different types of peripheral devices to the module. Pin configurations for the four SPI interface options are listed in Table 2. An example of this type of interfacing is shown in Figure 19 below. In the example below a generic EEPROM memory peripheral chip is connected to the BT121 using the SPI 1 Alt 2 option. Figure 19 Connecting an external device with BT121 using SPI interface
Bluegiga – A Silicon Labs Company 29 9.3 Connecting an external device using I2C interface Bluegiga Bluetooth Smart Ready module BT121 contains two physical I2C peripherals (I2C 1 and I2C 2). I2C 1 has two alternatives (Alt 1 and Alt 2) and I2C 2 one alternative (Alt 2). All of the three optional configurations can be used to connect different types of peripheral devices with the module. Pin configurations for the three I2C interface options are listed in Table 2. An example of this type of interfacing is shown in Figure 20 below. Note the pull-up resistors on the SDA and SCK lines. The example shows the address/chip select lines of the generic peripherals hardwired to VDD but in practice all or some of them would be wired to GPIO pins of the BT121 configured to work as chip select or address lines controlled by the application hardware. In the example below a generic sensor chip is connected to the BT121 using the I2C 1 Alt 1 option. Figure 20 Connecting to an I2C peripheral
Bluegiga – A Silicon Labs Company 30 Electrical characteristics 10.1 Absolute maximum ratings Parameter Min Max Unit Storage temperature -40 85 °C VDD -0.3 3.6 V 5V tolerant GPIO voltages -0.3 5.5 V Other terminal voltages -0.3 VDD+0.3 V Output current sourced or sunk by any GPIO pad 25 mA Current on all GPIO pads combined 120 mA Table 5 Absolute maximum ratings 10.2 Recommended operating conditions Rating Min Max Unit Operating temperature range -40 85 °C VDD 2.2 3.6 V VDD (when operating ADC or DAC) 2.4 3.6 V Table 6 Recommend operating conditions
Bluegiga – A Silicon Labs Company 31 10.3 Logic signal characteristics 10.3.1 Digital I/O Digital I/O pins Min Typ Max Unit Input voltage levels VIL input logic level low 1.7V ≤ VDD ≤ 3.6V -0.3 - 0.3VDD V VIH input logic level high 1.7V ≤ VDD ≤ 3.6V 0.7 VDD - VDD + 0.3 V Output voltage levels VOL output logic level low, Vdd = 3.6 V, Iol = 7 mA - - 0.4 V VOH output logic level high Vdd = 3.6 V, Ioh = -12 mA VDD - 0.4 - VDD V Table 7 Digital I/O pin electrical characteristics 10.3.2 Reset Power-on Reset Min Typ Max Unit Power on reset threshold (rising edge) 1.84 1.92 2.00 V Power on reset threshold (falling edge) 1.80 1.88 1.96 V RESET signal pulse width (pulled low) 500 - - ns Table 8 Reset pin characteristics 10.3.3 ADC Power-on Reset Min Typ Max Unit ADC input impedance - - 50 kohm ADC input voltage range 0 - VDD V ADC differential nonlinearity error - 0.7 1.3 LSB ADC integral nonlinearity error - 0.8 1.7 LSB ADC offset error - 1 2.8 LSB ADC gain error - 0.5 3 LSB Table 9 ADC pin characteristics
Bluegiga – A Silicon Labs Company 32 10.3.4 DAC Power-on Reset Min Typ Max Unit DAC output load impedance 5 - - kohm DAC output voltage range 0.2 - VDD - 0.2 V DAC differential nonlinearity - - 2 LSB DAC integral nonlinearity - - 4 LSB DAC offset error - - 12 LSB DAC gain error - - 0.5 % Table 10 DAC pin characteristics
Bluegiga – A Silicon Labs Company 33 10.4 Power consumption Operation state Current Unit Description CPU active 14 mA CPU active RF idle Power state 1 - RF idle 6.7 mA CPU idle RF idle Power state 2 - RF idle 92 µA CPU sleep RF idle Reset state 6-13 mA Reset-signal held low Continuous transmission - BDR 92 mA +12dBm, CPU active Continuous transmission - EDR 85 mA +12dBm, CPU active Table 11 Typical power consumption of different operating states Operation state Current Unit Description Idle, not visible, not connectable 6.0 mA Idle, visible, connectable 6.7 mA Inquiry 38.7 mA Connected, no data 11.1 mA Connected, no data, sniff 1s 6.6 mA Connected, continuous data 15.8 mA 115.2kbps over BGAPI Connected, continuous data, 1s sniff 7.2 mA 115.2kbps over BGAPI Table 12 Typical power consumption, Classic Bluetooth (Master mode, CPU sleep disabled) Operation state Current Unit Description Idle, visible, connectable 800 µA Inquiry 33 mA Connected, no data 5.1 mA Connected, no data, sniff 1s 520 µA
Bluegiga – A Silicon Labs Company 34 Connected, continuous data 15.8 mA 115kbps over BGAPI* Connected, continuous data, sniff 1s 7.2 mA 115kbps over BGAPI* Table 13 Typical power consumption, Classic Bluetooth (Master mode, CPU sleep enabled) *sleep controlled by wakeup pin, in the constant UART data streaming test the CPU is not allowed to enter sleep mode Operation state Current Unit Description Advertising, not connectable 1.4 mA 108ms Advertising, connectable 1.7 mA 108ms Advertising, not connectable 242 µA 1000ms Advertising, connectable 280 µA 1000ms Table 14 Typical power consumption, Bluetooth Low Energy (CPU sleep enabled)
Bluegiga – A Silicon Labs Company 35 RF Characteristics 11.1 Supported frequencies and channels Parameter Min Max Unit Frequency 2402 2480 MHz Channels 0 78 CH # Table 15 Supported frequencies and channels 11.2 Typical receiver sensitivity Packet type -40 to 85oC Unit DH1 -95 dBm 2DH1 -96 dBm 3DH3 -88 dBm LE -96 dBm Table 16 Typical receiver sensitivity 11.3 Transmitter output power Modulation type Min Typ Max Unit BDR (1 Mbps) 10 12 14 dBm EDR (2, 3 Mbps) 7 9 11 dBm LE 7 9 11 dBm Table 17 Transmitter output power at maximum setting 11.4 Carrier frequency accuracy Parameter Typ Max Bluetooth limit (total error) Unit Variation between individual units 3 10 +/- 25 ppm Variation with temperature (-40 to +85oC) 9 15 +/- 25 ppm Table 18 Carrier frequency accuracy
Bluegiga – A Silicon Labs Company 36 Physical dimensions Figure 21 BT121 module physical dimensions Figure 22 BT121 module recommended PCB pad pattern The 8 center pins of the module are reserved for production programming and should be left unsoldered but despite of this unmasked traces and vias should NOT be placed under the module in order to prevent short circuits.
Bluegiga – A Silicon Labs Company 37 Figure 23 BT121 module side view dimensions
Bluegiga – A Silicon Labs Company 38 Soldering recommendations Bluegiga Bluetooth Smart Ready module BT121 is compatible with the industrial standard reflow profile for Pb-free solders. The reflow profile to be used depends on the thermal mass of the entire populated application PCB, heat transfer efficiency of the oven and on the particular type of solder paste used. Consult the datasheet of the particular solder paste used for more detailed information regarding profile configurations. The following recommendations for soldering the module are to ensure reliable solder joints and operation of the module after soldering. Since the soldering profile used is process and layout dependent, the optimum profile should be studied and decided case by case. The following recommendation should be taken only as a starting point and should be adjusted according to more detailed instructions of the solder paste and soldering equipment manufacturers.  Check the recommended soldering profile configuration from the solder paste manufacturers documentation.  Avoid using more than one flow.  Reliability of the solder joints and self-alignment of the component are dependent on the solder volume. A minimum stencil thickness of 150 m is recommended.  Aperture size of the stencil should be 1:1 with the pad size.  A low residue, “no clean” solder paste should be used due to the low mounted height of the module.  If the vias used on the application board have a diameter larger than 0.3 mm, it is recommended to mask the via holes at the module side to prevent solder wicking through the via holes. Solders have a habit of filling holes and leaving voids in the thermal pad solder junction, as well as forming solder balls on the other side of the application board. These phenomena can in some cases cause problems.
Bluegiga – A Silicon Labs Company 39 13.1 Soldering profile example As an example of a typical soldering profile please see an example of a generic example of a reflow profile shown below. As stated in previous section soldering profiles are solder paste specific. Consult the manufacturer of the paste used. Figure 24 Reference reflow profile example
Bluegiga – A Silicon Labs Company 40 Tape and reel packaging This section contains information regarding the tape and reel packaging and materials of packaging with dimensions for the Bluegiga Bluetooth Smart Ready BT121 module. 14.1 Reel material and dimensions  Reel material PS Conductive Black – surface resistance 103 ↔ 105  Reel diameter 13”  Reel color Black Table 19 Reel dimensions 14.2 Tape material and dimensions  Tape material PS Conductive Black – surface resistance 103 ↔ 105 Table 20 Tape dimensions Symbol Dimensions [mm] D0 330.2 D1 100.0 W1 24.0 Symbol Dimensions [mm] P0 4.0 P1 16.0 D3 1.5 A0 11.3 B0 14.2 K0 2.7 W0 24.0 T 0.3
Bluegiga – A Silicon Labs Company 41 14.3 Tape and reel box dimensions Table 21 Tape and reel box dimensions 14.4 Module orientation in tape Figure 25 Module orientation in tape and feed direction Symbol Dimensions [mm] W1 338 W2 344 W3 44
Bluegiga – A Silicon Labs Company 42 Certifications BT121 compliance certifications are pending. 15.1 CE BT121 is in conformity with the essential requirements and other relevant requirements of the R&TTE Directive (1999/5/EC). The product is conformity with the following standards and/or normative documents.  EMC (immunity only) EN 301 489-17 V.1.3.2 in accordance with EN 301 489-1 V1.8.1  Radiated emissions EN 300 328 V1.8.1 15.2 FCC 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. Any changes or modifications not expressly approved by Bluegiga Technologies could void the user’s authority to operate the equipment. FCC RF Radiation Exposure Statement: This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. End users must follow the specific operating instructions for satisfying RF exposure compliance. This transmitter meets both portable and mobile limits as demonstrated in the RF Exposure Analysis. This transmitter must not be co-located or operating in conjunction with any other antenna or transmitter except in accordance with FCC multi-transmitter product procedures. As long as the condition above is met, further transmitter testing will not be required. However, the OEM integrator is still responsible for testing their end-product for any additional compliance requirements required with this module installed (for example, digital device emissions, PC peripheral requirements, etc.). OEM Responsibilities to comply with FCC Regulations The BT121 Module has been certified for integration into products only by OEM integrators under the following conditions:  The antenna(s) must be installed such that a minimum separation distance of 7 mm is maintained between the radiator (antenna) and all persons at all times.  The transmitter module must not be co-located or operating in conjunction with any other antenna or transmitter. As long as the two conditions above are met, further transmitter testing will not be required. However, the OEM integrator is still responsible for testing their end-product for any additional compliance requirements required with this module installed (for example, digital device emissions, PC peripheral requirements, etc.).
Bluegiga – A Silicon Labs Company 43 IMPORTANT NOTE: In the event that these conditions cannot be met (for certain configurations or co-location with another transmitter), then the FCC authorization is no longer considered valid and the FCC ID cannot be used on the final product. In these circumstances, the OEM integrator will be responsible for re-evaluating the end product (including the transmitter) and obtaining a separate FCC and Industry Canada authorization. End Product Labeling The BT121 module is labeled with its own FCC ID. If the FCC ID is not visible when the module is installed inside another device, then the outside of the device into which the module is installed must also display a label referring to the enclosed module. In that case, the final end product must be labeled in a visible area with the following: “Contains Transmitter Module FCC ID: QOQBT121” or “Contains FCC ID: QOQBT121 The OEM integrator has to be aware not to provide information to the end user regarding how to install or remove this RF module or change RF related parameters in the user manual of the end product. 15.3 IC TBA
Bluegiga – A Silicon Labs Company 44 Ordering information Product code Description BT121-A-V1 BT121 Bluetooth Smart Ready module with an integrated antenna BT121-A-V1-iAP BT121 Bluetooth Smart Ready module with an integrated antenna and Apple iAP profile. This part number is only available to Apple MFI licenses. DKBT Bluegiga Bluetooth Smart Ready Development kit
Bluegiga – A Silicon Labs Company 45 Contact Information Sales: www.bluegiga.com Technical Support: www.bluegiga.com/support Orders: bluegiga-orders@silabs.com WWW: www.bluegiga.com SILICON LABS Phone: +1 877.444.3032 400 West Cesar Chavez Austin, TX 78701 USA FINLAND OFFICE Phone: +358 9 435 5060 Fax: +358 9 435 50660 Sinikalliontie 5A, 5th floor 02630 Espoo, Finland

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