Ublox EVK-ANNA-B4 User manual

UBX-21008123 - R02
C1-Public www.u-blox.com
EVK-ANNA-B4
Evaluation kit for ANNA-B4 modules
User guide

Abstract
This document describes how to set up the EVK-ANNA-B4 evaluation kit to evaluate ANNA-
B4
series standalone Bluetooth®
5.1 low energy modules. It also describes the different options for
debugging and testing the development capabilities supported by the evaluation board.

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Document information
Title EVK-ANNA-B4
Subtitle Evaluation kit for ANNA-B4 modules
Document type User guide
Document number UBX-21008123
Revision and date R02 19-Oct-2021
Disclosure restriction C1-Public
This document applies to the following products:
Product name Type number Firmware version PCN reference
EVK-ANNA-B402U EVK-ANNA-B402U-00 N/A -
EVK-ANNA-B402C EVK-ANNA-B402C-00 N/A -
EVK-ANNA-B412U EVK-ANNA-B412U-00 All -
EVK-ANNA-B412C EVK-ANNA-B412C-00 All -
u
-blox or third parties may hold intellectual property rights in the products, names, logos 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 u-blox.
The information contained herein is provided “as is” and u
-blox assumes no liability for its use. No warranty, either express or
implied, is given, including but not limited to, with respect to the accuracy, correctnes
s, reliability and fitness for a particular
purpose of the information. This document may be revised by u
-blox at any time without notice. For the most recent
documents, visit www.u
-blox.com.
Copyright © u
-blox AG.

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Contents
Document information .............................................................................................................................2
Contents .......................................................................................................................................................3
1Quick start guide.................................................................................................................................5
1.1 Installing s-center evaluation software.................................................................................................. 5
1.2 Installing J-Link drivers .............................................................................................................................5
2Product description............................................................................................................................6
2.1 Overview........................................................................................................................................................6
2.2 Kit includes...................................................................................................................................................7
2.3 Key features .................................................................................................................................................7
2.4 EVK-ANNA-B4 block diagram ..................................................................................................................9
2.5 Connectors .................................................................................................................................................10
3Setting up the evaluation board.................................................................................................. 11
3.1 Software and hardware preparation.....................................................................................................11
Installing software............................................................................................................................11
Connecting external antennas.......................................................................................................11
Power on evaluation board..............................................................................................................11
Assigning COM ports.......................................................................................................................12
3.2 Starting up .................................................................................................................................................12
EVK-ANNA-B412 ..............................................................................................................................12
EVK-ANNA-B402 ..............................................................................................................................12
3.3 Measuring current consumption...........................................................................................................13
Using an amperemeter....................................................................................................................13
Using a voltmeter .............................................................................................................................13
Using an external power supply or power analyzer....................................................................14
4Board configuration......................................................................................................................... 15
4.1 Powering options.......................................................................................................................................15
Selecting the power configuration jumpers................................................................................15
Default power configuration, 3.3 V ...............................................................................................17
Battery powered, 3.0 – 1.7 V...........................................................................................................19
Battery powered with protection diode, 2.7 – 1.7 V...................................................................20
External supply, 3.6 – 1.7 V.............................................................................................................21
Raspberry Pi HAT..............................................................................................................................22
4.2 Disconnecting ANNA signals from board peripherals.......................................................................23
5Interfaces and peripherals ............................................................................................................ 25
5.1 Buttons and LEDs.....................................................................................................................................25
5.2 Arduino interface ......................................................................................................................................26
Arduino shield compatibility...........................................................................................................28
5.3 Raspberry Pi compatible interface ........................................................................................................28
Powering considerations.................................................................................................................31
UART ...................................................................................................................................................31

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EEPROM support..............................................................................................................................31
5.4 Additional Interfaces................................................................................................................................31
Extra USB to UART interface .........................................................................................................33
CPU trace interface ..........................................................................................................................33
Appendix .................................................................................................................................................... 34
ASchematics ........................................................................................................................................ 34
BAssembly drawings ......................................................................................................................... 38
CGlossary .............................................................................................................................................. 40
Related documents ................................................................................................................................ 41
Revision history ....................................................................................................................................... 41
Contact....................................................................................................................................................... 42

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1Quick start guide
EVK-ANNA-B4 software and documentation is available at www.u-blox.com/evk-search.
1.1 Installing s-center evaluation software
s-center is a powerful and easy-to-use tool for evaluating, configuring, and testing u-blox short range
modules. Running on Windows 10 operating systems, the software allows end users to assess and
configure u-blox short range modules using the EVK.
Follow the procedure outlined below to download and install the s-center software and
documentation. The software can be downloaded from the u-blox s-center product page and is
available free of charge.
1. Download the latest s-center software to your computer.
2. Open the s-center setup installer to install the software.
3. Select Launch button in the installer or open the application from the Windows Start button.
1.2 Installing J-Link drivers
Follow the procedure outlined below to install the J-Link drivers needed for programming the module.
1. Connect the EVK-ANNA-B4 board to your PC using the USB cable provided with the product.
2. Verify that the USB drivers are installed successfully. If the drivers do not install automatically,
see also Evaluation board setup.
3. Once the drivers are installed, a COM port is enabled in Windows. Use the Windows Device
Manager to view the COM port number for the USB serial port.
4. Start s-center to communicate with the module.
For EVK-ANNA-B4x2U (with external antenna), attach the antenna to the antenna cable and connect
the antenna cable to the U.FL connector.

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2Product description
2.1 Overview
The EVK-ANNA-B4 evaluation kit is a versatile development platform that allows quick prototyping of
a variety of extremely low-powered Internet of Things (IoT) applications, using full Bluetooth 5.1, NFC,
and IEEE 802.15.4.
EVK-ANNA-B4 boards are available in the following four variants that accommodate alternative
antenna and software solutions:
•EVK-ANNA-B402U – includes an open CPU ANNA-B402 module and U.FL antenna connector for
connecting to external antennas.
•EVK-ANNA-B402C – includes an open CPU ANNA-B402 module with an internal 2.4 GHz antenna
(integrated in the SiP).
•EVK-ANNA-B412U – includes an ANNA-B412 module, pre-flashed with u-connectXpress
software, and a U.FL antenna connector for connecting to external antennas.
•EVK-ANNA-B412C – includes an ANNA-B412 module, pre-flashed with u-connectXpress
software, and an internal 2.4 GHz antenna (integrated in the SiP).
(a) EVK-ANNA-B402U/B412U (b) EVK-ANNA-B402C/B412C
Figure 1: EVK-ANNA-B4 evaluation boards

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All ANNA-B4 standalone modules include an Arm®Cortex®-M4F microcontroller with a 64 MHz system
clock, 512 kB internal flash and 128 kB RAM.
EVK-ANNA-B4 evaluation boards provide access to the 33 GPIO pins and interfaces supported on
ANNA-B4 modules. The interfaces are available through a variety of connectors, including Arduino™
Uno R3 [1] and Raspberry Pi [2] header connectors. The boards also support simple USB drag-and-
drop programming and SEGGER J-Link debug interface that can be used with the open CPU variants
of the EVK.
Nordic Semiconductors, the manufacturer of the nRF52833 SoC, provide a free Software
Development Kit (SDK) that includes a broad selection of drivers, libraries, and example applications
that can be used for rapid prototyping.
2.2 Kit includes
The EVK-ANNA-B4 evaluation kit includes the following:
•ANNA-B4 evaluation board
•Two 2.4 GHz antennas with U.FL connector (only for EVK-ANNA-B402U and EVK-ANNA-B412U)
•NFC antenna
•USB cable
2.3 Key features
•ANNA-B402 Open CPU, based on Nordic nRF52833 SoC, Bluetooth 5.1 Low Energy modules:
oUltra-compact SiP (6.5 x 6.5) offering both internal and external antenna options
oOpen CPU for embedded application development
oIntegrated Arm®Cortex®-M4F microcontroller with 512kB internal flash and 128 kB RAM, and
64 MHz system clock
oFull Bluetooth 5.1 functionality including long range and direction finding (AoA/ AoD)
oNFC tag, Bluetooth mesh, Zigbee and Thread
oHW interfaces:
33 GPIO pins
2x UART
4x SPI
16x PWM capable outputs
8x analog capable inputs
2x I2C
1x I2S
1x PDM input
1x Quadrature decoder
1x USB 2.0
oWide 1.7-3.6 V supply range
oExtended temperature range up to +105 °C
oGlobal certification

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•ANNA-B412 with u-connectXpress software, based on Nordic nRF52833 SoC, Bluetooth 5.1 Low
Energy modules:
oUltra-compact SiP (6.5 x 6.5) offering both internal and external antenna options
oPre-flashed u-connectXpress software for accelerated time to market
oIntegrated Arm® Cortex®-M4F microcontroller with 64 MHz system clock
oPre-flashed u-connectXpress software supporting u-blox Bluetooth Low Energy Serial Port
Service, GATT client and server, beacons, Bluetooth long range, NFC™, and simultaneous
peripheral and central roles.
oDirection Finding (AoA/ AoD) capability, u-connectLocate is available on request
oHW interfaces:
19 GPIO pins
2x UART
oBluetooth mesh, available on request
oSuperior security functionality with secure boot
oWide 1.7-3.6 V supply range
oExtended temperature range up to +105 °C
oGlobal certification
•EVK-ANNA-B4xx evaluation boards:
oTwo EVK variants:
EVK-ANNA-B402 with ANNA-B402 Open CPU modules
EVK-ANNA-B412 with ANNA-B412 modules with u-connectXpress software
oFull UART to USB converter with a virtual COM port for control of the extended UART
features of the u-connectXpress software (EVK-ANNA-B412 only)
oOn-board J-Link debugger/programmer with:
Mass Storage Device interface to PC, for drag-and-drop programming
Debug port
Additional virtual COM port that connects to add-on boards, or debug UART on ANNA-B4
oDedicated USB connector for the ANNA-B402/B412 USB interface
oRGB LED and push buttons
oArduino UNO R3 and Raspberry Pi compatible pin header interfaces
oPin header connectors and level shifters allow for flexible power supply options with
different jumper connections for the ANNA- B402/B412 module. The jumpers can isolate the
module entirely from other functional parts of the evaluation board to save battery life and
control each power net separately to measure low-power applications precisely.
oMultiple board power supply options include:
5 V USB supply
5-12 V external power supply
5-12 V Arduino VIN input
3 V CR2032 coin cell battery

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2.4 EVK-ANNA-B4 block diagram
Figure 2 shows the major interfaces and internal connections supported on the EVK-ANNA-B4.
Figure 2: EVK-ANNA-B4 block diagram
UART
to USB
USB
conn.
Interface
MCU
(Program &
Debug Unit)
USB
Hub
USB
conn.
Batt.
holder
Power
plug
RF
conn.
Voltage
Level
Shifters
UART
SWD
3.3 V VCC_ANNA
DC/DC
reg.
Protect.
diodes
NFC antenna
connector
Dedicated ANNA
USB 2.0 conn.
VCC_ANNA
Bluetooth
802.15.4
Arduino Uno R3 interface
D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 SCL SDA
A0 A1 A2 A3 A4 A5
5V
VIN
GND
RESET
ADC/Comp. GPIO/Dig. Interface GPIO/Dig. Interface
UART
GPIO/Dig. Int.
UART
SW2
Raspberry Pi 40 pin GPIO header
3V3
5V
GND
GPIO/Digital Interface
UART
ID_SC ID_SD
RPi_3
RPi_4
RPi_5 RPi_6 RPi_7
RPi_2 RPi_8
RPi_9
RPi_10
RPi_11
RPi_12 RPi_13
RPi_14
RPi_15 RPi_16 RPi_17 RPi_18 RPi_19 RPi_20
RPi_21
RPi_22 RPi_23
RPi_24
RPi_25 RPi_26 RPi_27
ANNA
Module
User
RGB LED
User
buttons
Reset
button
ANNA
SWD conn.
ANNA signal
jumper header
SWD
UART
UART
COM port
pin header
Power selector
jumper headers
USB USB
USB
3.3 V
3.3 V
20-pin Trace
connector
ETM/ITM
Trace
USB
NFC
RF
VBUS
VBUS
CR2032
3 V
5 - 12 V
ANNA COM port
ANNA program & debug
Additional COM port
1.7 - 3.6 V
Raspberry Pi pin
ANNA Open CPU function
ANNA Open CPU function
Arduino pin
ANNA Connectivity Software function
ANNA Connectivity Software function
3V3
IOREF

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2.5 Connectors
Table 1 describes the available connectors of the EVK-ANNA-B4 shown in Figure 3.
Connector
Function Description
J5 Power supply 2.1 mm power jack. The center pin of the connector is the positive terminal. 5
– 12 V input.
J17 Power supply Pin header for connecting external power supplies. 5 – 12 V input.
BT1 Battery holder CR2032 coin cell battery holder. CR2032 usually has a 3 V potential when
fully charged.
J11 NFC antenna connector Pin header that connects to the u-blox NFC antenna included in the kit. The
antenna can be mounted in either direction.
J10 2.4 GHz RF antenna connector U.FL coaxial connector used to connect antennas or RF equipments. This
connector is only included in the EVK-ANNA-B402U/EVK-ANNA-B412U.
J12 Cortex Debug connector 10-pin, 50 mil pitch connector used to connect external debuggers to the
ANNA-B4 module. ANNA-B4 modules support Serial Wire debug (SWD) and
Serial Wire Viewer, but not JTAG debug.
J8 Power supply,
COM port and debug USB
The main USB connector used to program, debug, and communicate with the
ANNA module. It can also be used to power the entire board.
J6 Power supply and ANNA USB port Additional USB connector that connects directly to the ANNA-B4 USB
interface. The connector can also be used to power the entire board.
Table 1: EVK-ANNA-B4 connector description
Figure 3: Available connectors, pinout and designation
J5
21
1 4
GNDVIN
5 - 12 V
NFC1
GND GND
NFC2
U.FL RF coax
GND GND
N/C
VDD_IO
GND
SWDIO SWDCLK IO_16 N/C RESET_N
BT1
J17
Power
J8
J6
USB
Debug
J12
Antennas
J11
J10
CR2032
+
3V
2
1
10
9
Micro USB
Micro USB
Debug
Power
Antennas
USB
USB
J8
J5 BT1
J12
J6
J10
J11
Board Connectors
J17

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3Setting up the evaluation board
As introduced in Overview section, EVK-ANNA-B4 boards are available for four variants that
accommodate alternative antenna and software solutions.
Setting up EVK-ANNA-B402 evaluation boards for the open CPU ANNA-B402 modules and EVK-
ANNA-B412 evaluation boards for ANNA-B412 modules with pre-flashed u-connectXpress require
different software and hardware prerequisites.
3.1 Software and hardware preparation
Before setting up EVK-ANNA-B402 and EVK-ANNA-B412 evaluation boards, some software and
hardware prerequisites are needed.
Installing software
•EVK-ANNA-B402 evaluation boards only
J-Link drivers are needed for programming the open CPU ANNA-B402 modules. J-Link drivers are
usually automatically installed on a PC correctly when the evaluation boards are plugged in. If the
drivers are not installed automatically, download the J-Link driver included in the Nordic nRF
Command Line Tools and follow the procedure Installing J-Link drivers to install the J-Link drivers
needed for programming the open CPU ANNA-B402 modules. The drivers need only be installed
once when you connect the EVK to a new computer.
•EVK-ANNA-B412 evaluation boards only
EVK-ANNA-B412 evaluation boards are pre-flashed with u-connectXpress software which enables
users to configure ANNA-B412 modules using AT commands with u-blox s-center evaluation
software. Follow the procedure Installing s-center evaluation software to install the u-blox s-center
evaluation software.
Connecting external antennas
3.1.2.1 2.4 GHz antenna
To evaluate the 2.4 GHz radio on the EVK-ANNA-B402U and EVK-ANNA-B412U evaluation boards,
external antennas might be needed. Connect a 2.4 GHz antenna to the U.FL connector (J10) on the
ANNA-B402U or ANNA-B412U module if needed.
EVK-ANNA-B402C and EVK-ANNA-B412C board variants include internal antennas in the modules.
External antennas are therefore not needed for evaluating these board variants
3.1.2.2 NFC antenna
To use any of the EVK-ANNA-B4 board variants as an NFC tag, an NFC antenna can be connected to
the NFC antenna connector (J11) .
Power on evaluation board
Before powering on the evaluation boards, make sure that the power configuration jumpers are
connected according to your use cases, as described in Powering options. The default configuration
described in Selecting the power configuration jumpers works for most use cases.
Check the polarity of the EVK connector before connecting an external power supply to the EVK-
ANNA-B4 evaluation board. Center conductor is positive (+) and the ring is negative (-).

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Plug the external power supply to the power jack connector (J5), or connect a USB host to the USB
connector (J8) with a USB cable. Alternatively, you can power on a EVK-ANNA-B4 evaluation board
with a CR2032 coin cell battery. See also Powering options for more details.
Assigning COM ports
Two COM ports are automatically assigned to the device by Windows:
•The COM port labelled “USB Serial Port” is used to communicate with the UART interface of the
ANNA-B4 module.
•The COM port labelled “JLink CDC UART Port” can be used as an extra USB to the UART
interface. See also Extra USB to UART interface.
Windows 7
To view assigned COM ports on Windows 7:
1. Open the Control Panel and select Hardware and Sound.
2. Open the Device Manager in Devices and Printers. This opens the Device Manager window
where you can view the assigned COM ports.
Windows 10
To view assigned COM ports on Windows 10:
1. Right click the Windows Start button
2. Select Device Manager.
3.2 Starting up
EVK-ANNA-B412
3.2.1.1 u-connectXpress software
EVK-ANNA-B412 is equipped with ANNA-B412 module that runs the u-connectXpress software. The
software is preinstalled on the module.
☞Go to the u-blox support webpage to obtain the latest available software. Instructions on
reflashing the EVK-ANNA-B4 can be found in the Software section of the ANNA-B4 system
integration manual [4].
3.2.1.2 s-center evaluation software
To communicate with the ANNA-B412 modules using AT commands, set the baud rate to 115200
with 8N1 flow control. See also Quick start guide .
All available AT commands are described in the u-connect AT commands manual [6].
To get started with the basic use-case setup of EVK-ANNA-B412 with u-connectXpress software, see
the user guide [8].
EVK-ANNA-B402
3.2.2.1 Nordic Semiconductor SDK
To use the EVK-ANNA-B402 together with Nordic Semiconductor SDK it is necessary to:
•Create your own board file
•Adapt the examples in the Nordic Semiconductor SDK to use this board file
For more information about performing these tasks, see also the Software section of the ANNA-B4
system integration manual [4]. See also the u-blox short range open CPU github repository [9].

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3.2.2.2 Software debug options
Use either of the following options to debug software with EVK-ANNA-B402:
•Onboard debug solution available through the USB connector
•External debugger connected to J12 connector
An external debugger is useful when powering the evaluation board with a CR2032 coin cell battery or
an external power supply through the power jack connector J5. An external debugger is also useful
when the MCU interface has been disconnected from the ANNA-B402 module using the jumpers on
the J19 header.
SEGGER J-Link software [7] is necessary to debug with the onboard J-Link hardware on the EVK-
ANNA-B402.
3.3 Measuring current consumption
☞Before starting the current consumption measurement, check the Board configuration to
identify your chosen power configuration and find out what ANNA signals must subsequently be
isolated. The J22 jumper pins 1 and 3 must be removed to measure the current consumption.
Figure 4 shows some suggestions for connecting the various instruments when measuring module
current consumption.
Using an amperemeter
An amperemeter should be connected in series regardless of the power source and what is being
measured. In this way, the current can be measured when the ANNA module is supplied from either
the onboard 3.3 V regulator or an external supply.
Using a voltmeter
The EVK board must be modified before module current can be measured with a voltmeter.
To modify the board, solder a low resistance, high-tolerance, 0402 sized resistor to the footprint
labeled R6. This resistor replaces the jumper normally positioned between J22 pins - 1 and 3 so that
any current running through it produces a voltage across its terminals. Measure this voltage with the
voltmeter and calculate the current using Ohm’s law.

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Using an external power supply or power analyzer
To measure the power consumption of the ANNA modules, connect the instrument terminals to the
J22 pins, as shown in Figure 4.
Since the external voltage of any connected instrument can never perfectly match the 3.3 V
generated by the EVK, some small current leakage is apparent whenever the signal from the ANNA
module is connected to an EVK peripheral. The leakage is typically in the order of one to several
hundred nano amps.
To reduce leakage current, use a second external power channel to supply the EVK peripherals. This
second channel must also be used to enable PC communication when using any ANNA supply
voltages other than 3.3 V.
Figure 4: Different options when measuring current consumption of ANNA modules
J22
VCC_IO
VCC
1
GND
5
A
J22
VCC_IO
VCC
1
GND
5
A
6
4
R6
J22
VCC_IO
VCC
3
1
V
J22
VCC_IO
VCC
3
1
A
Amperemeter Voltmeter
One channel Two channels
GND GND
Onboard
3.3 V supply
DC/DC
External supply
1.7 - 3.6 V
-.-- V

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4Board configuration
4.1 Powering options
Power can be supplied to the board in any of the following ways:
•Through any of the USB connectors, J8 or J6
•Using the power jack, J5
•Through the Arduino interface, VIN pin.
•Using the Raspberry Pi interface 5V pins, J14.2 or J14.4
•Using the pin header, J17
•Plugging in a battery to the battery holder, BT1+
The power supply sources are distributed to the rest of the board as shown in Figure 5.
Figure 5: Block diagram of the power net distribution
Selecting the power configuration jumpers
EVK-ANNA-B4 offers flexible powering options for the ANNA-B4 module and the board itself. To
configure the power options, jumpers are added to or removed from pin headers to connect or
disconnect different power nets on the evaluation board. Figure 6 provides an overview of the available
power sources and targets. Figure 7 shows the location of the power configuration pin headers.
⚠Check the jumper positions carefully. Jumpers connected with incorrect polarity, can
permanently damage the components that are either ON or connected to the board. Note also
that some jumpers should not be mounted simultaneously. For instance, pins 5 and 6 and pins 7
and 8 on J7 connector should not be connected at the same time the battery is connected.
Diode protection
3.3 V
DC/DC
Regulator
Fuse
5 V
3.3 V
Diode protection
3 V
2.7 V
J7
Power select
pin header
J22
ANNA power select
pin header
VCC_ANNA
3.3 V
3.3 V
VIN
1.7 - 3.6 V
external supply
J1 and J14
Arduino and
Raspberry Pi
pin headers
VCC
VCC_IO
VDD_IO
ANNA
module
Board
peripherals
BT1
CR2032
3 V
J5
5 - 12 V
J8
5 V
J6
5 V
J17 pin 2
VIN pin header
5 - 12 V
J1 pin 8
Ardunio VIN pin
5 - 12 V
Diode protection
USB
conn.
Batt.
holder
Power
jack
USB
conn.

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Figure 6: Overview of EVK power sources and targets showing connected schematic net names
Figure 7: Pin header connectors J7 and J22 board location and pinout
DC/DC
Onboard 3.3 V
converter
Battery
Battery with
protection diode
MCU
PC communication
HAT
Raspberry Pi
expansion board
ANNA module power
Board I/O power:
Level shifters, LEDs etc.
3V3
VBAT_DIODE
VBAT
VDD_MCU
3V3_PI
VDD_IO
VCC
VCC_IO
Sources Net names Targets
Any power net
-.-- V
External supply
iguration
GND
GND
VDD_MCU
VCC_ANNA VCC_ANNA
VCC_ANNA
3V3_PI
3V3
3V3 VBAT VBAT_DIODE
3V3
J7
J22
1
11
12 2
J7
GND
GND
VDD_IO
VCC_IO
VCC_ANNA
VCC
5
6
21
J22
Power Conf

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Connector Pin no. Schematic
net
Description
J7 1 3V3 Regulated 3.3 V net. This net is supplied by the board and is always powered when a
power source is connected.
2 3V3_PI Connects to 3V3 pins of Raspberry Pi header connector J14. With a Raspberry Pi
device attached, this net must be left unconnected to prevent back currents. If an
add-on board HAT(Hardware Attached on Top) is connected, this net can be
connected to the EVK 3.3 V supply to power the HAT.
3 VBAT_DIODE To protect the battery from current back surges, connect the battery to the ANNA
module though a protection diode using this pin.
4 VCC_ANNA Connects to J22 pin 3 from which it can be connected to the module supply pin or
somewhere else
5 VBAT Connects to positive side of the battery terminal (BT1+)
6 VCC_ANNA Connects to J22 pin 3 from which it can be connected to the module supply pin or
somewhere else
7 3V3 Regulated 3.3 V net. This net is supplied by the board and is always powered when a
power source is connected.
8 VCC_ANNA Connects to J22 pin 3 from which it can be connected to the module supply pin or
somewhere else
9 3V3 Regulated 3.3 V net. This net is supplied by the board and is always powered when a
power source is connected.
10 VDD_MCU Supply net for board functions not directly connected to the ANNA module,
includinginterfaces to the MCU, USB hub, UART to USB converter, etc.
11 GND Ground net
12 GND Ground net
J22 1 VCC ANNA module voltage supply that connects to the module VCC pin. Connects to the
VCC_IO net through a 0 Ωresistor R4 by default.
2 VCC_IO Connects to the ANNA module VCC_IO pin and the VCC net through a 0 Ωresistor R4
by default
3 VCC_ANNA Connects to J7 pins 4, 6 and 8
4 VDD_IO Supply net for level shifters, LEDs and peripherals connected directly to the ANNA
module.
5 GND Ground net
6 GND Ground net
Table 2: Pinout of connectors J7 and J22 used to configure the board power nets
Default power configuration, 3.3 V
The out-of-box jumper positions for the EVK-ANNA power configuration are shown in Figure 8. In this
default configuration, the ANNA module is directly supplied by the EVK board with all board
peripherals powered up and everything running at 3.3 V.

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Figure 8: Jumper positions for default power configuration
Connector Add jumper to pins Description
J7 7, 8 Selects the board regulated 3.3 V net as source for the VCC_ANNA net
9, 10 Powers up interfaces to the MCU, USB hub, and UART to USB converter with 3.3 V
J22 1, 3 Powers up the ANNA module. The ANNA VCC and VCC_IO pins are connected to
the selected source for the VCC_ANNA net.
2, 4 Powers up peripherals directly connected to ANNA, such as LEDs and external
memory, from the module voltage supply.
Table 3: Jumper positions for default power configuration
J7
BOARD
RASP PI 3V3
3V3
3
4
21
J22
VCC_IO
VCC
1
2
9
10
ANNA module power
board I/O power
(optional)
J22: 2-4 J22: 1-3
PC communication
(optional)
MCU
J7: 9-10
ANNA
7
8
DC/DC
EVB powered
J7: 7-8
HAT
Raspberry Pi
expansion board
J7: 1-2
3V3
J7
BOARD
NINA
3V3
34
2 1
J22
VCC_IO
VCC
7
8
9
10
ANNA module powerboard I/O power
J22: 2-4 J22: 1-3
PC communication
MCU
DC/DC
EVB powered
J7: 9-10J7: 7-8

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Battery powered, 3.0 – 1.7 V
The configuration for using EVK-ANNA-B4 with a battery is shown Figure 9. In this configuration the
battery voltage is connected to VCC_ANNA, which in turn is connected to the ANNA-B4 VCC supply.
If necessary, add jumper to pins 2 and 4 of J22 to supply LEDs and other peripherals with power – but
only if this does not exceed the maximum current rating of the battery. If the ANNA module must be
configured, add jumper to pins 9 and 10 of J7 to connect the VDD_MCU net and enable
communications between a PC and the ANNA module.
☞Pins 9 and10 of J7 and pins 2 and 4 of J22 must be connected to communicate with the ANNA
module from a PC. As connecting an extra board peripheral might deplete the battery, the EVB
power configuration should be switched to the default 3.3 V configuration.
⚠To avoid damage to the battery, do not connect pins 5 and 6 and pins 7 and 8 on J7 at the same
time the battery is connected.
Figure 9: Jumper positions for battery powered operation, the jumpers shown in dashed lines are optional
Connector Add jumper to pins Description
J7 5, 6 Selects the battery connected to the battery holder as the source for the VCC_ANNA net
9, 10 (Optional) Powers up interfaces to the MCU, USB hub, and UART to USB converter with
3.3 V
J22 1, 3 Powers up the ANNA module. The ANNA VCC and VCC_IO pins are connected to the
chosen source for the VCC_ANNA net.
2, 4 (Optional) Powers up peripherals directly connected to the ANNA module, such as LEDs
and external memory, using the voltage supply to the module.
Table 4: Jumper positions for battery powered operation, two jumpers are optional
J7
BOARD
BATT
3V3
34
2 1
J22
VCC_IO
VCC
5
6
9
10
ANNA module powerboard I/O power
(optional)
J22: 2-4 J22: 1-3
PC communication
(optional)
MCU
J7: 9-10
Battery powered
J7: 5-6

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Battery powered with protection diode, 2.7 – 1.7 V
This power configuration protects the battery from current back surges. When using the NFC
interface, there is a risk that the applied electromagnetic field can cause back surges on the module
power lines. These back surges can damage a non-chargeable battery.
To block current back surges, connect pins 3 and 4 (instead pins 5 and 6) of J7 to add a schottky diode
in series with the battery, as shown in Figure 10.
☞The diode lowers the battery voltage level by ~0.3 V.
Figure 10: Jumper positions for battery-powered operation with a protection diode (dashed lines show optional jumpers)
Connector Add jumper to pins Description
J7 3, 4 Selects the diode-protected battery as a source for the VCC_ANNA net
9, 10 (Optional) Powers up the Interface MCU, USB hub, and UART to USB converter with 3.3 V.
J22 1, 3 Powers up the ANNA module. The ANNA VCC and VCC_IO pins are connected to the
selected source for the VCC_ANNA net.
2, 4 (Optional) Powers up the peripherals directly connected to ANNA such as LEDs and
external memory with the ANNA supply voltage.
Table 5: Jumper positions for battery powered operation with a protection diode (with two optional jumpers)
J7
BOARD
BATT DIODE
3V3
34
2 1
J22
VCC_IO
VCC
3
4
9
10
ANNA module powerboard I/O power
(optional)
J22: 2-4 J22: 1-3
PC communication
(optional)
MCU
J7: 9-10
J7: 3-4
Battery powered
with protection