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ANNA-B112 - System integration manual 

UBX-18009821 - R09 

System description

  

Page 18 of 66 

C1-Public 

 

 

Choose an antenna with optimal radiating characteristics for the best electrical performance and 
overall module functionality. An internal antenna integrated on the application board, or an external 
antenna connected to the application board through a proper 50 

 connector, can be used. 

While using an external antenna, the PCB-to-RF-cable transition must be implemented using either a 
suitable 50 

  connector, or an RF-signal solder pad (including GND) that is optimized for 50 

 

characteristic impedance. 

 

Antenna matching  

The antenna return loss should be as good as possible across the entire band when the system is 
operational to provide optimal performance. The enclosure, shields, other components and 
surrounding environment will impact the return loss seen at the antenna port. Matching components 
are often required to re-tune the antenna to bring the return loss within an acceptable range. 

It is difficult to predict the actual matching values for the antenna in the final form factor. Therefore, 
it is a good practice to have a placeholder in the circuit with a “pi” network, with two shunt components 
and a series component in the middle, to allow maximum flexibility while tuning the matching to the 
antenna feed. 

 

Approved antenna designs 

ANNA-B112 module comes with a pre-certified design that can be used to save costs and time during 
the certification process. The antenna path is routed to a U.FL connector and the external antenna is 
connected to the U.FL connector. 

To take advantage of the ANNA-B112 certification, the customer is required to implement antenna 
layout according to u-blox reference design. The reference design is described in Appendix

 B. 

The designer integrating a u-blox reference design into an end-product is solely responsible for the 
unintentional emission levels produced by the end-product. 

The module may be integrated with other antennas. In this case, the OEM installer must certify his 
design with respective regulatory agencies. 

1.10.3

 

NFC antenna 

The ANNA-B112 module includes a Near Field Communication interface, capable of operating as a 
13.56 MHz NFC tag at a bit rate of 106 kbps. As an NFC tag, data can be read from or written to the 
ANNA-B112 modules using an NFC reader; however, the ANNA-B112 module is not capable of reading 
other tags or initiating NFC communications. Two pins are available for connecting to an external NFC 
antenna: 

NFC1

 and 

NFC2

 

Reserved pins (RSVD) 

Do not connect reserved (

RSVD

) pin. The reserved pins can be allocated for future interfaces and 

functionality. 

 

GND pins 

Good connection of the module's GND pins with solid ground layer of the host application board is 
required for correct RF performance. It significantly reduces EMC issues and provides a thermal heat 
sink for the module.  

See the Module  footprint  and paste mask  and  thermal guidelines  sections for information about 
ground design. 

Summary of Contents for ANNA-B112

Page 1: ...integration of ANNA B112 stand alone Bluetooth low energy modules With embedded Bluetooth low energy stack and u connectXpress software this module is tailored for OEMs who wish to have the shortest...

Page 2: ...gos and designs included in this document Copying reproduction modification or disclosure to third parties of this document or any part thereof is only permitted with the express written permission of...

Page 3: ...10 1 6 1 External crystal 10 1 6 2 Internal oscillator 11 1 6 3 External clock source 11 1 6 4 Low power clock settings for u connectXpress software 12 1 6 5 Selecting clock source 14 Debug serial wi...

Page 4: ...interface 45 3 5 1 Battery protection 45 General High Speed layout guidelines 46 3 6 1 General considerations for schematic design and PCB floor planning 46 3 6 2 Module placement 46 3 6 3 Layout and...

Page 5: ...s Page 5 of 66 C1 Public B 3 Reference design for external antennas U FL connector 59 B 4 Examples of application ground plane miniaturizations 61 B 4 1 Example application 1 61 B 4 2 Example applicat...

Page 6: ...rvice GATT client and server beacons NFC and simultaneous peripheral and central roles all configurable from a host by using AT commands The OEMs can also embed their own application using for example...

Page 7: ...ANNA B112 System integration manual UBX 18009821 R09 System description Page 7 of 66 C1 Public Product features Table 1 ANNA B112 main features summary...

Page 8: ...he ANNA B112 module The different software options are described in more detail in section 2 The u connectXpress SW comes with a separate mesh SW variant that is available for download only The ANNA B...

Page 9: ...a battery the I O voltage level will vary with the battery output voltage depending on the charge of the battery Level shifters might be needed depending on the I O voltage of the host system 1 4 3 V...

Page 10: ...lock The ANNA B112 module uses a 32 768 kHz low power clock to enable different sleep modes This clock can be generated from an internal or external clock source Different options for generating the c...

Page 11: ...clock stability 1 6 3 External clock source An external clock source generated from for example a host CPU can also be used The clock source can be either low swing signal or full swing signal The ele...

Page 12: ...nly once The only way to clear the settings is to erase the flash memory See section 2 3 2 for details on SWD flashing This section describes the AT command and the available settings for the low powe...

Page 13: ...10 PPM 9 5 PPM 10 2 PPM 11 1 PPM value2 Number When source 0 internal oscillator default 2 Temperature change calibration interval 0 Always calibrate even if the temperature has not changed 1 Invalid...

Page 14: ...e of current is negligible So if the application will be in standby for longer periods of time then an external crystal might be worth adding Table 7 shows the average current consumption for a beacon...

Page 15: ...ed to make the UART available either as test points or connected to a header for software upgrade The IO level of the UART will follow the VCC voltage and it can thus be in the range of 1 8 V and 3 6...

Page 16: ...analog Analog comparator input Compare two voltages capable of generating wake up events and interrupts Any analog PWM output Output complex pulse width modulation waveforms Any Connection status ind...

Page 17: ...tions 1 10 1 Integrated antenna The ANNA B112 is equipped with a certified integrated antenna in the module To take advantage of the ANNA B112 certification the customer is required to implement the s...

Page 18: ...ied design that can be used to save costs and time during the certification process The antenna path is routed to a U FL connector and the external antenna is connected to the U FL connector To take a...

Page 19: ...with the preflashed u connectXpress software The u connectXpress software enables the use of the Bluetooth Low Energy functions controlled by AT commands over the UART interface Examples of supported...

Page 20: ...nd extract the latest nRF5 SDK available at http www nordicsemi com eng Products Bluetooth low energy nRF5 SDK Save the software container to the directory you want to use with the nRF5 SDK 4 Read the...

Page 21: ...ode on different platforms 1 Add a build configuration in the Segger Studio project ifndef BOARD_CUSTOM_H define BOARD_CUSTOM_H ifdef __cplusplus extern C endif include nrf_gpio h In this case PIN 25...

Page 22: ...SDK Figure 6 Setting up board configuration to use evk_anna_b1 h board file The build for your configuration now uses your custom board file 2 2 2 Zephyr Zephyr 16 is a widely adopted open source Rea...

Page 23: ...m the u blox shortrange open CPU github repository 17 You can copy the configuration to the install directory zephyr boards arm folder and the build the project from your preferred environment Buildin...

Page 24: ...TOS and drivers for sensors and I O devices With an RTOS core based on the widely used open source CMSIS RTOS RTX Arm Mbed OS supports deterministic multithreaded real time software execution Arm Mbed...

Page 25: ...T_NRF5 TARGET_MCU_NRF52832 For EVK ANNA B1 the folder is called TARGET_UBLOX_EVK_ANNA_B112 In this new folder there should be two files device h and PinNames h 1 device h contains the include object h...

Page 26: ...ANNA B112 Figure 10 PinNames h Example code for EVK ANNA B112 ifndef MBED_PINNAMES_H define MBED_PINNAMES_H include cmsis h ifdef __cplusplus extern C endif typedef enum PIN_INPUT PIN_OUTPUT PinDirect...

Page 27: ...ANNA_B112_IO_35 p19 ANNA_B112_IO_36 p22 ANNA_B112_IO_37 p23 ANNA_B112_IO_38 p24 ANNA_B112_IO_45 p20 EVK ANNA B112 board LED1 ANNA_B112_IO_29 Red LED2 ANNA_B112_IO_30 Green SW1 LED3 ANNA_B112_IO_31 Bl...

Page 28: ...with an empty flash The MAC address is programmed in the CUSTOMER 0 and CUSTOMER 1 user information configuration registers of the of the nRF52832 chip The address can be read and written using eithe...

Page 29: ...NNA B112 70B module variants do not have any software preloaded and must be flashed over SWD Flashing of u connectXpress software is normally done over UART If the flash is erased or any other softwar...

Page 30: ...ce 2 ANNA B112 SWx x x bin contains the application 3 ANNA B112 Configuration x x x json contains the bin file name flash address size and crc for the SoftDevice It also includes the bin file name and...

Page 31: ...rminal application 1 Connect to the module using Tera Term and set the serial settings as shown in Figure 13 Figure 13 Screenshot that shows serial settings 2 Start the bootloader mode using either of...

Page 32: ...ce information from the json configuration file Figure 15 Screenshot that shows file transfer mode 4 When the bootloader displays ccc see also Figure 15 it is ready to receive the SoftDevice bin file...

Page 33: ...nse indicates a successful file transfer Figure 18 Screenshot shown on successful file transfer 6 Verify the transferred file using the command c SOFTDEVICE SoftDevice size SoftDevice CRC32 The size a...

Page 34: ...shown on successful verification of the transferred file Flashing the application software 1 Use command x Application address to set the bootloader in file transfer mode The application address can...

Page 35: ...dy to receive the application bin file Figure 23 Screenshot shown during file transfer 3 Send the file using the XMODEM protocol as shown in Figure 23 Figure 24 Screenshot showing how to send the file...

Page 36: ...ic Semiconductor to flash the module The external debugger SEGGER J Link BASE is verified to work with ANNA B112 The EVK ANNA B112 evaluation kit incorporates an on board debugger and can therefore be...

Page 37: ...ox webpage the following hex files are available for u connectXpress software SoftDevice s132_nrf52_xxx hex Bootloader ANNA B112_BOOT_xxx hex Application ANNA B112_SW_xxx hex u connectXpress software...

Page 38: ...e nrfjprog utility as described in section 2 2 5 Restoring the Bluetooth device address When the new u connectXpress software has been flashed to the module it is important to restore the Bluetooth de...

Page 39: ...out design 9 System functions RESET_N I2C GPIO and other System input and output pins 10 Accurate design is required to guarantee that the voltage level is well defined during module boot 11 Other pin...

Page 40: ...cted with minimum insertion losses Additional insertion loss will be introduced by low quality or long cable Large insertion loss reduces radiation performance A high quality 50 coaxial connector prov...

Page 41: ...to comply with the radiation exposure limits specified by regulatory agencies Table 13 Summary of antenna interface requirements for ANNA B112 In both the cases while selecting external or internal an...

Page 42: ...r are recommended to reduce losses Stack up should allow for thick 50 traces and at least 200 m trace width is recommended to assure good impedance control over the PCB manufacturing process FR 4 mate...

Page 43: ...oaxial cable may be relatively fragile compared to other types of cables To increase application ruggedness connect U FL connector to a more robust connector such as SMA fixed on panel A de facto stan...

Page 44: ...ntenna close to buses such as DDR or consider taking specific countermeasures like metal shields or ferrite sheets to reduce the interference Take care of interaction between co located RF systems lik...

Page 45: ...will give tuning capacitors in the range of 130 pF on each pin For good performance match the total capacitance on NFC1 and NFC2 The ANNA B112 module have been tested with a 3x3 cm PCB trace antenna...

Page 46: ...tenna to high frequency busses like DDRs and other related components or consider an optional metal shield to reduce interferences that could otherwise be picked up by the antenna and subsequently red...

Page 47: ...e EMC Directive 89 336 EEC and the Low Voltage Directive 73 23 EEC issued by the Commission of the European Community Compliance with these directives implies conformity to the following European Norm...

Page 48: ...I EN 301 489 1 ETSI EN 301 489 7 ETSI EN 301 489 24 ANNA B112 is manufactured with consideration to specific standards that minimize the occurrence of ESD events The highly automated process complies...

Page 49: ...nt of contact when handling the PCB must always be between the local GND and PCB GND Before mounting an antenna patch connect ground of the device When handling the RF pin do not come into contact wit...

Page 50: ...ss and PCB layout Process parameter Unit Value Pre heat Ramp up rate to TSMIN K s 3 TSMIN C 150 TSMAX C 200 tS from 25 C s 110 tS Pre heat s 60 Peak TL C 217 tL time above TL s 60 TP absolute max C 24...

Page 51: ...0 17 Modulus 25 C MPa 20000 Modulus 260 C MPa 500 Table 17 Parameters potting If the antenna and or antenna trace is covered by the potting it will affect the RF characteristics of the module This mig...

Page 52: ...d in detail to improve the production quality This is achieved with automatic test equipment ATE in production line which logs all production and measurement data A detailed test report for each unit...

Page 53: ...e result The standard operational module firmware and test software on the host can be used to perform functional tests communication with the host controller check interfaces and to perform basic RF...

Page 54: ...I2C Inter Integrated Circuit JSON JavaScript Object Notation LDO Low Drop Out LED Light Emitting Diode MAC Media Access Control MSL Moisture Sensitivity Level NSMD Non Solder Mask Defined PCB Printed...

Page 55: ...lidated parts for antenna matching PCB layout must be identical to the one provided by u blox Implement one of the reference designs included in this section or contact u blox The designer must use th...

Page 56: ...NA B112 System integration manual UBX 18009821 R09 Appendix Page 56 of 66 C1 Public Figure 30 Reference design for internal antenna corner version top layer Traces and vias for other signals not prese...

Page 57: ...Traces and vias for other signals not present B 2 Internal antenna reference design with module along PCB edge When using the ANNA B112 together with this antenna reference design the circuit trace la...

Page 58: ...age 58 of 66 C1 Public Figure 32 Reference design for internal antenna edge version top layer Traces and vias for other signals are not present Figure 33 Reference design for internal antenna edge ver...

Page 59: ...ust be kept as indicated in the reference design The reference design uses a micro coaxial connector that is connected to the external antenna via a 50 pigtail This section describes where the critica...

Page 60: ...r signals are not present The 50 coplanar micro strip dimensions used in the reference design are stated in Figure 36 and Table 20 The GND plane beneath the RF trace must be intact Figure 36 Coplanar...

Page 61: ...the left as shown in Figure 3737 is the first example that shows what can be achieved by shrinking the board size The below graph visualizes the correlation between the total radiated power TRP and t...

Page 62: ...atterns Integrating the graph the TRP is achieved 5 67 dBm A spherical shape is ideal B 4 2 Example application 2 The tiny device in Figure 4040 is an example of building with both range and miniaturi...

Page 63: ...40 A tiny ANNA B1 application including coin cell battery with the range of about 100 m size 7 5 x 12 mm Theta 60 Phi 45 Theta 1 4 Phi 189 5 Figure 41 The tiny ANNA B1 graphs show the total radiation...

Page 64: ...ces from electrostatic phenomena General requirements 10 ETSI EN 60950 1 2006 Information technology equipment Safety Part 1 General requirements 11 FCC Regulatory Information Title 47 Telecommunicati...

Page 65: ...tenna reference designs appendix B Replaced u blox connectivity software with u connectXpress software in all instances Replaced all references to the ANNA B112 GettingStarted guide with the new docum...

Page 66: ...om Regional Office China Beijing Phone 86 10 68 133 545 E mail info_cn u blox com Support support_cn u blox com Regional Office China Chongqing Phone 86 23 6815 1588 E mail info_cn u blox com Support...

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