UG554 xG27 Development Kit
Product Information
The xG27 Dev Kit is a low-cost, small form factor prototype and
development platform for the EFR32BG27 Wireless Gecko
System-on-Chip. It is a small and cost-effective, feature-rich
platform based on the EFR32TM Wireless Gecko System-on-Chip. The
xG27 Dev Kit is an ideal platform for developing energy-friendly
connected IoT devices. It comes with a Bluetooth demo that works
with a cloud connected smartphone app, showcasing easy collection
of environmental and motion sensor data, as well as button and LED
control. The kit also includes a built-in SEGGER J-Link debugger
for easy debugging through the USB Micro-B connector.
Product Usage Instructions
- Kit Contents:
- Check that the xG27 Dev Kit includes all the necessary
components mentioned in the kit contents section of the user
manual.
- Check that the xG27 Dev Kit includes all the necessary
- Getting Started:
- Refer to the getting started section of the user manual for
step-by-step instructions on how to set up and power on the xG27
Dev Kit.
- Refer to the getting started section of the user manual for
- Hardware Content:
- Review the hardware content section of the user manual to
understand the different components and connectors present on the
xG27 Dev Kit.
- Review the hardware content section of the user manual to
- Kit Hardware Layout:
- Refer to the kit hardware layout section of the user manual to
get a visual representation of the layout and placement of various
hardware components on the xG27 Dev Kit.
- Refer to the kit hardware layout section of the user manual to
- Specifications:
- Review the recommended operating conditions and current
consumption mentioned in the specifications section of the user
manual to ensure proper usage of the xG27 Dev Kit.
- Review the recommended operating conditions and current
- Block Diagram:
- Refer to the block diagram section of the user manual to get a
high-level overview of the internal components and their
interconnections on the xG27 Dev Kit.
- Refer to the block diagram section of the user manual to get a
- Power Supply:
- Follow the instructions provided in the power supply section of
the user manual to correctly connect and provide power to the xG27
Dev Kit.
- Follow the instructions provided in the power supply section of
- EFR32BG27 Reset:
- Learn about the EFR32BG27 reset mechanism and how to perform a
reset on the xG27 Dev Kit by referring to the EFR32BG27 reset
section of the user manual.
- Learn about the EFR32BG27 reset mechanism and how to perform a
- On-board Debugger:
- Understand how to use the built-in SEGGER J-Link debugger for
easy debugging of the xG27 Dev Kit by following the instructions
mentioned in the on-board debugger section of the user manual.
- Understand how to use the built-in SEGGER J-Link debugger for
- Connectors:
- Get detailed information about the different connectors on the
xG27 Dev Kit, including breakout pads, mini simplicity connector,
and debug USB Type-C connector, by referring to the connectors
section of the user manual.
- Get detailed information about the different connectors on the
- Debugging:
- Learn about different debugging options available for the xG27
Dev Kit, including on-board debugger, external debugger, and
virtual COM port, by reading the debugging section of the user
manual.
- Learn about different debugging options available for the xG27
- EMC Regulations for 2.4 GHz:
- Refer to the EMC regulations section of the user manual to
understand the emission limits and compliance recommendations for
operating the xG27 Dev Kit in the 2.4 GHz frequency band.
- Refer to the EMC regulations section of the user manual to
UG554: xG27 Dev Kit User’s Guide
The xG27 Dev Kit is a low-cost, small form factor prototype and development platform for the EFR32BG27 Wireless Gecko System-on-Chip.
The board is a small and cost-effective, feature-rich, prototype and development platform based on the EFR32TM Wireless Gecko System-on-Chip. The xG27 Dev Kit is an ideal platform for developing energy-friendly connected IoT devices.
The xG27 Dev Kit ships with a Bluetooth demo that works with a cloud connected smartphone app, showcasing easy collection of environmental and motion sensor data, as well as button and LED control.
A built in SEGGER J-Link debugger ensures easy debugging through the USB Micro-B connector.
TARGET DEVICE
· EFR32 Wireless Gecko System-on-Chip (EFR32BG27C140F768IM40) · Cortex-M33 w/FPU with 76.8 MHz maximum operating frequency · 512 kB flash and 32 kB RAM · Energy-efficient radio core with low active and sleep currents · Bluetooth 5.2 Direction Finding · Integrated PA with up to 8 dBm (2.4 GHz) TX power · Secure Boot with Root of Trust and Secure Loader (RTSL)
KIT FEATURES
· 2.4 GHz ceramic chip antenna · Power control of on-board peripherals for
ultra-low-power operation · Relative humidity and temperature sensor · Ambient light sensor · Hall effect sensor · 6-axis inertial sensor · PDM stereo microphones · 8 Mbit flash for OTA programming and
data logging · User LED and push button · 20-pin 2.54 mm breakout pads · SEGGER J-Link on-board debugger · Virtual COM port · Packet Trace Interface (PTI) · Mini Simplicity connector for AEM and
packet trace using external Silicon Labs debugger · USB or coin cell battery powered.
SOFTWARE SUPPORT
· Simplicity StudioTM
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Copyright © 2023 by Silicon Laboratories
Rev. 1.0
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1 Kit Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 Getting Started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.3 Hardware Content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.4 Kit Hardware Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.1 Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Current Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3. Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.1 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
3.3 EFR32BG27 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
3.4 Peripherals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 3.4.1 Si7021 Relative Humidity and Temperature Sensor . . . . . . . . . . . . . . . .12 3.4.2 Si7210 Hall Effect Sensor . . . . . . . . . . . . . . . . . . . . . . . . .12 3.4.3 VEML6035 Ambient Light Sensor . . . . . . . . . . . . . . . . . . . . . .13 3.4.4 PDM Stereo Microphones . . . . . . . . . . . . . . . . . . . . . . . . .13 3.4.5 ICM-20648 6-Axis Inertial Sensor . . . . . . . . . . . . . . . . . . . . . .14 3.4.6 Push Button and LED . . . . . . . . . . . . . . . . . . . . . . . . . .15 3.4.7 External Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
3.5 On-board Debugger . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
3.6 Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17 3.6.1 Breakout Pads . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 3.6.2 Mini Simplicity Connector . . . . . . . . . . . . . . . . . . . . . . . . .19 3.6.3 Debug USB Type-C Connector . . . . . . . . . . . . . . . . . . . . . . .19
4. Debugging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 4.1 On-board Debugger . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
4.2 External Debugger. . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
4.3 Virtual COM Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
5. Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 5.1 RF Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 5.1.1 Description of the RF Matching . . . . . . . . . . . . . . . . . . . . . . .22 5.1.2 RF Section Power Supply . . . . . . . . . . . . . . . . . . . . . . . . .22 5.1.3 RF Matching Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . .22 5.1.4 Antenna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23 5.1.5 Antenna Matching Bill of Materials . . . . . . . . . . . . . . . . . . . . . .23
5.2 EMC Regulations for 2.4 GHz . . . . . . . . . . . . . . . . . . . . . . . . .24 5.2.1 ETSI EN 300-328 Emission Limits for the 2400-2483.5 MHz Band . . . . . . . . . . .24 5.2.2 FCC15.247 Emission Limits for the 2400-2483.5 MHz Band . . . . . . . . . . . . .24
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5.2.3 Applied Emission Limits . . . . . . . . . . . . . . . . . . . . . . . . .24 5.3 Relaxation with Modulated Carrier . . . . . . . . . . . . . . . . . . . . . . .24 5.4 Radiated Power Measurements . . . . . . . . . . . . . . . . . . . . . . . .25
5.4.1 Maximum Radiated Power Measurement . . . . . . . . . . . . . . . . . . .25 5.4.2 Antenna Pattern Measurement . . . . . . . . . . . . . . . . . . . . . . .26 5.5 EMC Compliance Recommendations . . . . . . . . . . . . . . . . . . . . . .28 5.5.1 Recommendations for 2.4 GHz ETSI EN 300-328 Compliance . . . . . . . . . . . .28 5.5.2 Recommendations for 2.4 GHz FCC 15.247 Compliance . . . . . . . . . . . . . .28
6. Schematics, Assembly Drawings, and BOM . . . . . . . . . . . . . . . . . . . 29
7. Kit Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
8. Board Revision History and Errata . . . . . . . . . . . . . . . . . . . . . . 31 8.1 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 8.2 Errata . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
9. Document Revision History . . . . . . . . . . . . . . . . . . . . . . . . . 32
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UG554: xG27 Dev Kit User’s Guide
Introduction
1. Introduction
The xG27 Dev Kit (OPN: xG27-DK2602A) has been designed to inspire customers to make battery-operated IoT devices with the Silicon Labs EFR32BG27 Wireless Gecko System-on-Chip. The highlights of the board include four different environmental sensors and stereo PDM microphones accessible to the EFR32BG27 wireless MCU. The peripherals have been grouped into power domains that can be turned on and off by the application code as needed.
Programming the xG27 Dev Kit is easily done using a USB Micro-B cable and the on-board J-Link debugger. A USB virtual COM port provides a serial connection to the target application, and the Packet Trace Interface (PTI) offers invaluable debug information about transmitted and received packets in wireless links. Included on the board is an 8 Mbit serial flash that can be used for Over-The-Air (OTA) firmware upgrade, or as a general purpose non-volatile memory. The xG27 Dev Kit is supported in Simplicity StudioTM, and a Board Support Package (BSP) is provided to give application developers a flying start.
Energy profiling and advanced wireless network analysis and debugging tools are available through the provided Mini Simplicity Connector using an external Silicon Labs debugger.
Connecting external hardware to the xG27 Dev Kit can be done using the 20 breakout pads, which present peripherals from the EFR32BG27 Wireless Gecko such as I2C, SPI, UART, and GPIOs. The breakout pads follow the same pinout as the expansion headers (EXP) on other Silicon Labs Starter Kits.
1.1 Kit Contents
The following items are included in the box: · 1x xG27 Dev Kit board (BRD2602A).
1.2 Getting Started
Detailed instructions for how to get started with your new xG27 Dev Kit can be found on the Silicon Labs web page: https:// www.silabs.com/dev-tools
1.3 Hardware Content
The following key hardware elements are included on the xG27 Dev Kit: · EFR32BG27 Wireless Gecko SoC with 76.8 MHz operating frequency, 512 kB flash, and 32 kB RAM · 2.4 GHz ceramic antenna for wireless transmission · Silicon Labs Si7021 relative humidity and temperature sensor · Silicon Labs Si7210 hall effect sensor · Vishay VEML6035 ambient light sensor · TDK InvenSense ICM-20689 6-axis inertial sensor · Two Knowles SPK0641HT4H-1 MEMS microphones · Macronix ultra low power 8 Mbit SPI flash (MX25R8035F) · One LED and one push button · Power enable signals and isolation switches for ultra-low power operation · On-board SEGGER J-Link debugger for easy programming and debugging, which includes a USB virtual COM port and Packet
Trace Interface (PTI) · Mini Simplicity connector for access to energy profiling and advanced wireless network debugging · Breakout pads for GPIO access and connection to external hardware · Reset button · Automatic switchover between USB and battery power · CR2032 coin cell holder
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UG554: xG27 Dev Kit User’s Guide
Introduction
1.4 Kit Hardware Layout xG27 Dev Kit layout is shown below.
Left PDM Microphone
2.4 GHz Chip Antenna EFR32BG27
Wireless Gecko
Top View
Right PDM Microphone
30.4 mm Bottom View
Hall Effect Sensor
Reset Button
20-pin EXP-header Breakout Pads
6-axis Inertial Sensor
LED
Ambient Light Sensor
On-board USB J-Link Debugger
Mini Simplicity Connector
45.4 mm
Push Button
USB Micro-B Connector – Virtual COM port – Debug access – Packet trace
Humidity and Temperature Sensor
CR2032 Coin Cell Holder
Figure 1.1. xG27 Dev Kit Hardware Layout
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2. Specifications
UG554: xG27 Dev Kit User’s Guide
Specifications
2.1 Recommended Operating Conditions The following table provides guidelines for correct use of the xG27 Dev Kit, indicating typical operating conditions and some design limits.
Table 2.1. Recommended Operating Conditions
Parameter
Symbol
Min
Typ
Max
Unit
USB Supply Input Voltage
VUSB
—
5.0
—
V
Battery Supply Input Voltage
VVBAT
2.0
3.0
3.3
V
Supply Input Voltage (VMCU supplied externally)1,2
VVMCU
2.0
3.0
3.6
V
Operating Temperature
TOP
—
20
—
°C
Note: 1. The maximum supply voltage may be less under certain conditions when using the EFR32BG27’s dc-dc converter. For more information, see the EFR32BG27 data sheet.
2. Not recommended for use with rechargeable Lithium batteries. Most Li-Ion and Li-Po cells exceed 3.6 V when fully charged.
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UG554: xG27 Dev Kit User’s Guide
Specifications
2.2 Current Consumption
The table below summarizes the data sheet current consumption of the various components on the board. The operating current of the board greatly depends on the application. The number of enabled sensors, how often they are sampled, and how often the radio is transmitting or receiving are examples of factors that influence the operating current. In many cases the given conditions differ from the operating conditions on the xG27 Dev Kit, but the table can still be used as an indication of how much each feature contributes to the total current consumption. More details can be found in the specific data sheet for each device.
Table 2.2. Current Consumption
Parameter EFR32BG27 Current Consumption1
Ambient Light Sensor Current Consumption 2 RH/Temp Sensor Current Consumption3
Hall Effect Magnetic Sensor Current Consumption 4
Microphone Current Consumption5 IMU Current Consumption6
Serial Flash Memory Current Consumption 7
Symbol IEFR32
IVEML6035 ISi7021 IDD IMIC IIMU IFlash
Condition
MCU current consumption in EM0 mode with all peripherals disabled (dc-dc converter at 3.0 V input and 1.8 V output, VSCALE1, 38.4 MHz crystal, CPU running Prime from flash at 25 °C)
EM4, no BURTC, no LF oscillator
Radio system current consumption in receive mode, active packet reception (dc-dc converter at 3.0 V input and 1.8 V output, MCU in EM1 and all MCU peripherals disabled, HCLK = 38.4 MHz, 1Mbit/s, 2GFSK, f = 2.4 GHz, VSCALE1 at 25 °C)
Radio system current consumption in transmit mode (dcdc converter at 3.0 V input and 1.8 V output, MCU in EM1 and all MCU peripherals disabled, HCLK = 38.4 MHz, f = 2.4 GHz, CW, 8 dBm output power, VSCALE1 at 25 °C)
Shutdown at 1.8 V
Operation mode at 1.8 V (ALS only)
Standby, -40 to +85°C
RH conversion in progress
Temperature conversion in progress
Peak IDD during I2C operations
Sleep mode at 3.3 V
Average current for periodic activation at 3.3 V, sleep timer enabled, 200 msec sleep time
Conversion in progress at 3.3 V
Sleep mode current (Fclock = 0 Hz, VDD = 3.6 V)
Supply current in performance mode (VDD = 3.6 V, Fclock = 2.4 MHz)
Full-chip sleep mode at 1.8 V supply
Gyroscope only, 100 Hz update rate at 1.8 V supply
Accelerometer only, 100 Hz update rate at 1.8 V supply
Gyroscope + Accelerometer, 100 Hz update rate at 1.8 V supply
Deep power-down current in ultra-low-power mode at 1.8 V
Standby current in ultra-low-power mode at 1.8 V
Write status register current in ultra-low-power mode at 1.8 V
Typ 30
0.18 4
11.5
0.5 170 0.06 150 90 3.5 50 0.4
5 26 700
6 1.6 57 1.9 0.007 5 3.1
Unit µA/MHz
µA mA
mA
µA µA µA µA µA mA nA µA mA µA µA
µA mA µA mA µA µA mA
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UG554: xG27 Dev Kit User’s Guide
Specifications
Parameter
Symbol
Condition
Typ
Unit
On-board Debugger Sleep
IDBG
On-board debugger current consumption when USB cable
80
nA
Current Consumption 8
is not inserted (EFM32GG12 EM4S mode current con-
sumption)
Minimum Board Current
IBOARD Minimum total board current consumption for VMCU = 3.0
0.4
µA
Consumption
V with EFR32BG27 in EM4S, the USB cable disconnec-
ted, and all peripherals either in sleep mode or disconnec-
ted
Note: 1. From EFM32BG27 data sheet 2. From VEML6035 data sheet 3. From Si7021-A20 data sheet 4. From Si7210 data sheet 5. From SPK0641HT4H-1 data sheet 6. From ICM-20648 data sheet 7. From MX25R8035F data sheet 8. From EFM32GG12 data sheet
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UG554: xG27 Dev Kit User’s Guide
Hardware
3. Hardware
The core of the xG27 Dev Kit is the EFR32BG27 Wireless Gecko System-on-Chip. The board also contains several peripherals connected to the EFR32BG27. Refer to section 1.4 Kit Hardware Layout for hardware component placement and layout information.
3.1 Block Diagram An overview of the xG27 Dev Kit is illustrated in the figure below.
Device Connectivity & Debugging
USB Micro-B Connector
J-Link Debugger
Mini-Simplicity Breakout Pads
Connector
(EXP-Header pinout)
Radio
2.4 GHz Antenna Memory
8 Mbit MX25R
Serial Flash
EFR32BG27 Wireless SoC
Button and LED
User Button & LED
Sensors Si7021
VEML6035
Si7210
Temperature & Humidity
Sensor
Ambient Light Sensor
SPK0641HT4H-1 ICM-20648
Hall Effect Sensor
2x PDM Microphones
6-axis Inertial Sensor
Figure 3.1. Kit Block Diagram
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Hardware
3.2 Power Supply
The kit can be powered through one of these interfaces:
· USB Type-C · Battery · Mini Simplicity connector
The figure below shows the power options available on the kit and illustrates the main system power architecture.
Battery
Automatic Switchover
VMCU
Mini Simplicity Connector
5V0
3V0
USB Micro-B
IN
OUT
LDO
Peripherals
Peripherals
Peripherals
EFR32BG27 Wireless SoC Peripherals
Figure 3.2. xG27 Dev Kit Power Architecture
Power is normally applied either through the USB cable or a CR2032 battery. When the USB cable is connected, VBUS is regulated down to 3.0 V. An automatic switchover circuit switches the main system power from battery power to USB power when the USB cable is inserted and protects the battery from reverse current. Power can also be applied through the Mini Simplicity connector. This requires that no other power sources are present on the kit, as power is injected directly to the VMCU net. It is important to follow this process to avoid power conflicts and backfeeding the battery. Powering the xG27 Dev Kit through the Mini Simplicity connector allows current measurements using the Advanced Energy Monitoring (AEM) as described in section 4.2 External Debugger. Important: When powering the board through the Mini Simplicity connector, the USB and battery power sources must be removed.
The power supply options are summarized in the table below.
Table 3.1. xG27 Dev Kit Power Options
Supply Mode USB power
CR2032 battery Mini Simplicity
Typical Input Voltage 5.0 V 3.0 V 3.3 V
VMCU Source On-board regulator
Battery voltage Debugger dependent
3V0 On-board regulator
Disconnected Disconnected
5V USB VBUS No voltage present No voltage present
3.3 EFR32BG27 Reset
The EFR32BG27 can be reset by a few different sources: · A user pressing the RESET button. · The on-board debugger pulling the #RESET pin low. · An external debugger pulling the #RESET pin low.
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Hardware
3.4 Peripherals
The xG27 Dev Kit contains a set of peripherals that can be accessed from the EFR32BG27. All the peripherals have enable signals which can be used to completely turn off the peripherals that are not in use, or they can be put into a state that draws a minuscule amount of power. This allows for the lowest possible power consumption in every application. The following peripherals are accessible to the EFR32BG27:
· One Silicon Labs Si7021 relative humidity & temperature sensor · One Silicon Labs Si7210 hall effect sensor · One Vishay VEML6035 ambient light sensor · One TDK InvenSense ICM-20648 6-axis inertial measurement sensor · Two Knowles SPK0641HT4H-1 MEMS microphones with PDM output · One Macronix MX25R8035F ultra-low-power 8 Mbit SPI flash · One LED and one push button
The figure below gives an overview of the peripherals that are connected to the EFR32BG27. Note that some of the peripherals share the same interface and enable signals. As the enable signals do not have external pull-down resistors on the board, the application code should actively drive the signals either low or high to prevent the lines from floating.
ICM-20648
IMU INTERRUPT IMU ENABLE VMCU
VMCU
2x SPK0641HT4H-1
SPI IMU CS
SPI 3
MX25R
VMCU
EFR32BG27
8 Mbit Flash
SPI FLASH CS
PC10 (I2C0_SCL#14) PC11 (I2C0_SDA#16)
PDM 2
MIC ENABLE
VMCU
I2C 2
SENSOR ENABLE
Si7021 VEML6035 Si7210
Button
GPIO
GPIO
LED
Figure 3.3. Peripherals
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UG554: xG27 Dev Kit User’s Guide
Hardware
3.4.1 Si7021 Relative Humidity and Temperature Sensor
The Si7021 I2C relative humidity and temperature sensor is a monolithic CMOS IC integrating humidity and temperature sensor elements, an analog-to-digital converter, signal processing, calibration data, and an I2C interface. The patented use of industry-standard, low-K polymeric dielectrics for sensing humidity enables the construction of low-power, monolithic CMOS Sensor ICs with low drift and hysteresis, and excellent long term stability. The Si7021 offers an accurate, low-power, factory-calibrated digital solution ideal for measuring humidity, dew-point, and temperature in applications ranging from HVAC/R and asset tracking to industrial and consumer platforms.
On the xG27 Dev Kit, the Si7021 is connected through a switch. The switch must therefore be enabled by setting EFR32_SENSOR_EN high before it can be used by the application. This enables power to the Si7021 and connects the I2C lines used for the sensor to the EFR32BG27 I2C bus. The application code should always drive the EFR32_SENSOR_EN signal either high or low to prevent it from floating. The figure below shows how the Si7021 is connected to the EFR32BG27.
EFR32BG27
VMCU
VDD_SENSOR
Si7021
PD03 (I2C0.SCL) EFR32_I2C_SCL PD02 (I2C0.SDA) EFR32_I2C_SDA
PC06 (GPIO) EFR32_SENSOR_ENABLE
SENSOR_I2C_SCL SENSOR_I2C_SDA
0: Sensor is not powered 1: Sensor is powered
Temperature & Humidity
Sensor
Figure 3.4. Si7021 Relative Humidity and Temperature Sensor
Although measures have been taken to thermally isolate the sensor from the board, temperature readings will be influenced when power is dissipated on the board. More accurate temperature measurements are achieved when powering the board with a battery or through the Mini Simplicity connector as self-heating from the on-board LDO is eliminated and the on-board debugger is put in a lowpower state.
3.4.2 Si7210 Hall Effect Sensor
The Si7210 family of Hall effect sensors from Silicon Labs combines a chopper-stabilized Hall element with a low-noise analog amplifier, 13-bit analog-to-digital converter, and an I2C interface. Leveraging Silicon Labs’ proven CMOS design techniques, the Si7210 family incorporates digital signal processing to provide precise compensation for temperature and offset drift. The 13-bit magnetic field strength can be read through the I2C interface at any time. Applications for the Si7210 include mechanical position sensing in consumer, industrial, and automotive applications, reed switch replacement, fluid level measurement, speed sensing, and control knobs, and switches.
On the xG27 Dev Kit, the Si7210 is connected through a switch. The switch must therefore be enabled by setting EFR32_SENSOR_EN high before it can be used by the application. This enables power to the Si7210 and connects the I2C lines used for the sensor to the EFR32BG27 I2C bus. The application code should always drive the EFR32_SENSOR_EN signal either high or low to prevent it from floating. The figure below shows how the Si7210 is connected to the EFR32BG27.
EFR32BG27
VMCU
VDD_SENSOR
Si7210
PD03 (I2C0.SCL) EFR32_I2C_SCL PD02 (I2C0.SDA) EFR32_I2C_SDA
PC06 (GPIO) EFR32_SENSOR_ENABLE
SENSOR_I2C_SCL SENSOR_I2C_SDA
0: Sensor is not powered 1: Sensor is powered
Hall Effect Sensor
Figure 3.5. Hall Effect Sensor
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Hardware
3.4.3 VEML6035 Ambient Light Sensor
The VEML6035 is an ambient light sensor with I2C digital interface.
On the xG27 Dev Kit, the VEML6035 is connected through a switch. The switch must therefore be enabled by setting EFR32_SENSOR_EN high before it can be used by the application. This enables power to the VEML6035 and connects the I2C lines used for the sensor to the EFR32BG27 I2C bus. The application code should always drive the EFR32_SENSOR_EN signal either high or low to prevent it from floating. The figure below shows how the VEML6035 is connected to the EFR32BG27.
EFR32BG27
VMCU
VDD_SENSOR
VEML6035
PD03 (I2C0.SCL) EFR32_I2C_SCL PD02 (I2C0.SDA) EFR32_I2C_SDA
PC06 (GPIO) EFR32_SENSOR_ENABLE
SENSOR_I2C_SCL SENSOR_I2C_SDA
0: Sensor is not powered 1: Sensor is powered
Ambient Light Sensor
Figure 3.6. VEML6035 Ambient Light Sensor
3.4.4 PDM Stereo Microphones
The xG27 Dev Kit features two Knowles SPK0641HT4H-1 digital MEMS microphones with PDM output. The microphones are configured to form a stereo sound input device using only a single PDM data line. The clock to the microphones are fed from a pin on EFR32BG27 with PDM clock support. The output from both microphones are connected to the same line and connected to a pin on the EFR32BG27 supporting PDM data input.
On the xG27 Dev Kit, the microphones are connected through a switch. The switch must therefore be enabled by setting EFR32_MIC_EN high before it can be used by the application. This enables power to the microphones and connects the PDM lines used for the sensor to the EFR32BG27. The application code should always drive the EFR32_MIC_EN signal either high or low to prevent it from floating. The figure below shows how the microphones are connected to the EFR32BG27.
EFR32BG27
VMCU
PB00 (PDM.CLK) EFR32_PDM_CLK PB01 (PDM.DAT0) EFR32_PDM_DATA
PC07 (GPIO) EFR32_MIC_ENABLE
VDD_MIC
MIC_PDM_CLK MIC_PDM_DATA 0: Sensor is not powered 1: Sensor is powered
SPK0641HT4H-1
VDD_MIC
PDM Microphone (R)
SPK0641HT4H-1
VDD_MIC
PDM Microphone (L)
Figure 3.7. Digital Stereo Microphones
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3.4.5 ICM-20648 6-Axis Inertial Sensor
The ICM-20648 is a 6-axis inertial sensor consisting of a 3-axis gyroscope and a 3-axis accelerometer. The sensor detects acceleration and angular rate in and around the X-, Y- and Z-axes with integrated 16-bit ADCs and programmable digital filters.
On the xG27 Dev Kit, the ICM-20648 is connected through a switch. The switch must be enabled by setting EFR32_IMU_EN high before it can be used by the application. This enables power to the ICM-20648 and connects the SPI lines used for the sensor to the EFR32BG27 SPI bus. The application code should always drive the EFR32_IMU_EN signal either high or low to prevent it from floating. Note the presence of the external pull-up resistor on the interrupt line as this can cause back powering if not handled correctly in software. The figure below shows how the ICM-20648 is connected to the EFR32BG27.
EFR32BG27
VMCU
VDD_IMU
PC02 (US0.CLK) GPIO_SPI_MOSI GPIO_SPI_MISO
PB02 (US0.CS)
EFR32_SPI_SCLK NET_TARGET_SPI_MOSI NET_TARGET_SPI_MISO EFR32_SPI_IMU_CS#
PB04 (GPIO) EFR32_IMU_ENABLE
PA00 (GPIO)
IMU_SPI_SCLK NET_IMU_SPI_MOSI NET_IMU_SPI_MISO IMU_SPI_CS#
0: Sensor is not powered 1: Sensor is powered
EFR32_IMU_INT
ICM-20648
6-axis Intertial Sensor
Figure 3.8. ICM-20648 Six-axis Inertial Sensor
The inertial sensor is located close to the geometrical center of the board. The coordinate system and rotation of the sensor follows the right-hand rule, and the spatial orientation of the board is shown in the figure below.
Figure 3.9. xG27 Dev Kit Spatial Orientation
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3.4.6 Push Button and LED
The kit has one user push button, marked BTN0, that is connected to a GPIO on the EFR32BG27. The button is connected to pin PB03 and it is debounced by an RC filter with a time constant of 1 ms. The logic state of the button is high while the button is not being pressed, and low when the button is pressed.
The kit also features one yellow LED, marked LED0, that is controlled by a GPIO pin on the EFR32BG27. The LED is connected to pin PA04 in an active-high configuration.
EFR32BG27
PB03 (GPIO.EM4WU4) PA04 (GPIO)
EFR32_BUTTON0 EFR32_LED0
User Button & LED
Figure 3.10. Button and LED
3.4.6.1 GPIOs on Unused JTAG Debug Pins
The EFR32BG27 allows the PA04 pin, which is connected to TDI on the JTAG Debug Port, to be used for other purposes if JTAG is not used. The xG27 Dev Kit uses SWD as debugging interface and the PA04 pin of the EFR32BG27 is used to control LED0. Under certain circumstances, such as an unexpected reset during a debug session, control of the PA04 pin can be transferred to the debug port which will result in the user application losing control of the PA04 pin. If this happens, known workarounds are to disconnect all active debug sessions and then reset the EFR32BG27 through either the reset pin or by toggling the power.
3.4.7 External Memory
The xG27 Dev Kit includes an 8 Mbit Macronix SPI Flash that is connected directly to the EFR32BG27. The MX25R series are ultra-low power serial flash devices, so there is no need for a separate enable switch to keep current consumption down. However, it is important that the flash is always put in deep power down mode when not used. This is done by issuing a command over the SPI interface. In deep power down, the MX25R typically adds approximately 100 nA to the current consumption. The figure below shows how the serial flash is connected to the EFR32BG27.
EFR32BG27
VMCU
PC02 (US0.CLK) GPIO_SPI_MOSI GPIO_SPI_MISO
PC03 (US0.CS)
EFR32_SPI_SCLK NET_SPI_MOSI NET_SPI_MISO EFR32_SPI_FLASH_CS#
flash_size Mbit MX25R
Serial Flash
Figure 3.11. Serial Flash
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3.5 On-board Debugger
The xG27 Dev Kit contains a microcontroller separate from the EFR32BG27 Wireless Gecko that provides the user with an on-board JLink debugger through the USB Type-C port. This microcontroller is referred to as the “on-board debugger” and is not programmable by the user. When the USB cable is removed, the on-board debugger goes into a very low power shutoff mode (EM4S).
In addition to providing code download and debug features, the on-board debugger also presents a virtual COM port for general purpose application serial data transfer. The Packet Trace Interface (PTI) is also supported which offers invaluable debug information about transmitted and received packets in wireless links.
The figure below shows the connections between the target EFR32BG27 device and the on-board debugger. The figure also shows the Mini Simplicity Connector, and how this is connected to the same I/O pins.
Refer to section 4. Debugging for more details on debugging.
Mini Simplicity Connector EFERF3R23B2GM2G7
Host PC
DBG_VCOM_TX
DBG_VCOM_RX
USB
On-Board
DBG_VCOM_CTS
J-Link
DBG_VCOM_RTS
Debugger
DBG_SWCLK
DBG_SWDIO
DBG_SWO
DBG_PTI_DATA DBG_PTI_FRAME
DBG_RESET
PA05 (USART1.TX) PA06 (USART1.RX) PA08 (USART1.CTS) PA07 (USART1.RTS) PA01 (GPIO.SWCLK) PA02 (GPIO.SWDIO) PA03 (GPIO.SWV) PC04 (FRC.DOUT) PC05 (FRC.DFRAME) RESETn
Figure 3.12. On-Board Debugger Connections
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3.6 Connectors
The xG27 Dev Kit features a Mini Simplicity Connector, a USB Type-C connector, and 20 breakout pads that follow the EXP header pinout. The connectors are placed on the top side of the board, and their placement and pinout are shown in the figure below. For additional information on the connectors, see the following sub-chapters.
Expansion Header Breakout Pads
GND – EXP1
1
PA8 – EXP3
3
PA7 – EXP5
5
PB0 – EXP7
7
PB1 – EXP9
9
PA4 – EXP11
11
PB3 – EXP13
13
PD3 – I2C_SCL – EXP15
15
BOARD_ID_SCL – EXP17
17
BOARD_ID_SDA – EXP19
19
Mini-Simplicity
Connector
2
EXP2 – VMCU
4
EXP4 – SPI_MOSI – PC0
6
EXP6 – SPI_MISO – PC1
8
EXP8 – SPI_SCLK – PC2
10
EXP10 – SPI_CS – PB2
12
EXP12 – UART_TX – PA5
14
EXP14 – UART_RX – PA6
16
EXP16 – I2C_SDA – PD2
18
EXP18 – 5V
20
EXP20 – 3V0
USB Micro-B Connector
PTI_DATA – PC4 SWCLK – PA1 SWO – PA3
VCOM_RX – PA6 GND
Mini Simplicity Connector
PC5 – PTI_FRAME PA2 – SWDIO PA5 – VCOM_TX RST VMCU
Pin 1
Figure 3.13. xG27 Dev Kit Connectors
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3.6.1 Breakout Pads
Twenty breakout pads, which follow the EXP header pinout, are provided and allow connection of peripherals or add-on boards. Ten of the pads are located along the left side of the board and ten are located on the right side. The breakout pads expose I/O pins that can be used with most of the EFR32BG27’s features. Additionally, the VMCU (main power rail), 3V0 (LDO regulator output), and 5V power rails are also exposed.
The breakout pads are pinned out similar to the EXP header found on other Silicon Labs Starter Kits, which ensures that commonly used peripherals such as SPI, UART, and I2C buses are available on fixed locations. The rest of the pins are used for general purpose IO. The EXP header allows the definition of EXP boards that can plug into a number of different Silicon Labs starter kits.
The pin-routing on EFR32 is very flexible, so most peripherals can be routed to any pin. However, pins may be shared between the breakout pads and other functions on the xG27 Dev Kit. The table below includes an overview of the EXP header and functionality that is shared with the kit.
Table 3.2. Expansion Header Pinout
Pin
Connection
EXP Header Function
Shared Feature
Right-side Breakout Pins
2
VMCU
EFR32BG27 voltage domain, included in AEM measurements.
4
PC00
SPI_COPI
IMU & Flash
6
PC01
SPI_CIPO
IMU & Flash
8
PC02
SPI_SCLK
IMU & Flash
10
PB02
SPI_CS
IMU
12
PA05
UART_TX
Virtual COM Port
14
PA06
UART_RX
Virtual COM Port
16
PD02
I2C_SDA
Sensor I2C bus
18
5V
Board USB voltage
20
3V0
Board controller supply
Left-side Breakout Pins
1
GND
Ground
3
PA08
GPIO
Virtual COM Port
5
PA07
GPIO
Virtual COM Port
7
PB00
GPIO
PDM Microphones
9
PB01
GPIO
PDM Microphones
11
PA04
GPIO
LED
13
PB03
GPIO
Button
15
PD03
I2C_SCL
Sensor I2C bus
17
BOARD_ID_SCL Connected to Board Controller for identification of add-on boards.
19
BOARD_ID_SDA Connected to Board Controller for identification of add-on boards.
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3.6.2 Mini Simplicity Connector
The Mini Simplicity connector is a 10-pin, 1.27 mm pitch connector that allows the use of an external debugger such as the one found on a Silicon Labs Wireless Starter Kit mainboard. See section 4.2 External Debugger for more details. The pinout of the connector on the board is described in the table below with the names being referenced from the EFR32BG27.
Table 3.3. Mini Simplicity Connector Pin Descriptions
Pin number 1
2 3 4 5 6 7 8 9 10
Function AEM
GND RST VCOM_RX VCOM_TX SWO SWDIO SWCLK PTI_FRAME PTI_DATA
Connection VMCU
GND RESET PA06 PA05 PA03 PA02 PA01 PC05 PC04
Description Target voltage on the debugged application. May be supplied and monitored by the AEM on an external debugger. Ground EFR32BG27 reset Virtual COM Rx Virtual COM Tx Serial Wire Output Serial Wire Data Serial Wire Clock Packet Trace Frame Packet Trace Data
3.6.3 Debug USB Type-C Connector
The debug USB port can be used for uploading code, debugging, and as a Virtual COM port. More information is available in section 4. Debugging.
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Debugging
4. Debugging
The xG27 Dev Kit contains an on-board SEGGER J-Link Debugger that interfaces to the target EFR32BG27 using the Serial Wire Debug (SWD) interface. The debugger allows the user to download code and debug applications running in the target EFR32BG27. Additionally, it also provides a VCOM port to the host computer that is connected to the target device’s serial port for general purpose communication between the running application and the host computer. The Packet Trace Interface (PTI) is also supported by the on-board debugger which offers invaluable debug information about transmitted and received packets in wireless links. The on-board debugger is accessible through the USB Type-C connector.
An external debugger can be used instead of the on-board debugger by connecting it to the Mini Simplicity Connector. This allows advanced debugging features as described in section 4.2 External Debugger. When using an external debugger it is very important to make sure that there is no power source present on the xG27 Dev Kit, as the external debugger might source a voltage on the target power domain (VMCU).
Important: When connecting an external debugger that sources voltage to the VMCU net, the USB cable and battery must be removed from the xG27 Dev Kit. Failure to do so will create power conflicts.
The figure below shows the possible debug options.
Figure 4.1. xG27 Dev Kit Debugging Possibilities
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4.1 On-board Debugger
The on-board debugger is a SEGGER J-Link debugger running on an EFM32 Giant Gecko. The debugger is directly connected to the debug and VCOM pins of the target EFR32BG27.
When the debug USB cable is inserted, the on-board debugger is automatically activated, and takes control of the debug and VCOM interfaces. This means that debug and communication will not work with an external debugger connected at the same time. The onboard LDO is also activated, providing power to the board.
When the USB cable is removed, the board might still be running on battery power, as described in section . In this case, the on-board debugger goes into a very low power shutoff mode (EM4S), consuming about 80 nA. This means that battery lifetime will not be affected too much by the on-board debugger power consumption. Since the I/O voltage rail of the debugger remains powered in the battery operated mode, the pins connected to the debug and VCOM interfaces maintain proper isolation and prevent leakage currents.
4.2 External Debugger
A Wireless mainboard from Silicon Labs can be connected to the Mini Simplicity Connector and used for debugging instead of the onboard debugger. For instruction on using the mainboard for debugging, see AN958: Debugging and Programming Interfaces for Custom Designs. Note that the Wireless STK Mainboard (BRD4001A) requires a BRD8010A STK/WSTK Debug Adapter to get access to the Mini Simplicity Connector. Debugging with an external Wireless mainboard gives access to the following debugging features:
· Debugging of the target device through SWD · Communication using the VCOM port · Packet Trace Interface (for wireless devices only) · Advanced Energy Monitor
Note that the Mini Simplicity Connector cannot be used at the same time that the on-board debugger is active (USB cable is plugged in). For information on how to correctly connect to the kit, see Figure 4.1 xG27 Dev Kit Debugging Possibilities on page 20.
Powering the board when using the Mini Simplicity Connector with a Wireless mainboard can be done using the AEM voltage supply of the Wireless mainboard. When doing this, remove both the USB cable and the coin cell battery from the xG27 Dev Kit before connecting the Wireless mainboard to the Mini Simplicity Connector. The power switch on the Wireless mainboard should be set in “AEM”. Power-cycling of the board, if necessary, is easily done by flipping the power switch on the Wireless to “BAT” and back to “AEM”, assuming a battery is not inserted in the Wireless mainboard.
It is possible to have the xG27 Dev Kit powered by a battery and still use the Mini Simplicity Connector with a Wireless mainboard for debugging and communication. In this case, the power switch on the Wireless mainboard must be set to the “BAT” position and the coin cell battery on the Wireless mainboard must be removed. In this case, level shifters on the Wireless mainboard itself take care of interfacing to different voltage levels on the xG27 Dev Kit. Connecting the board to an external debugger in other ways than those described above might create power conflicts, compromise the ability to monitor power consumption, and hazardously feed power back to the on-board battery.
Important: Always remove the battery if you are not sure whether the external debugger is sourcing voltage to xG27 Dev Kit.
4.3 Virtual COM Port
The virtual COM port (VCOM) is a connection to a UART on the EFR32BG27 and allows serial data to be sent and received from the device. The on-board debugger presents this connection as a virtual COM port on the host computer that shows up when the USB cable is inserted.
Data is transferred between the host computer and the debugger through the USB connection, which emulates a serial port using the USB Communication Device Class (CDC). From the debugger, the data is passed on to the target device through a physical UART connection.
The serial format is 115200 bps, 8 bits, no parity, and 1 stop bit by default.
Note: Changing the baud rate for the COM port on the PC side does not influence the UART baud rate between the debugger and the target device. However, it is possible to change the VCOM baud rate through the kits’ Admin Console available through Simplicity Studio.
Alternatively, the VCOM port can also be used through the Mini Simplicity Connector with an external Wireless mainboard. Using the VCOM port through the Mini Simplicity Connector with an external Wireless mainboard works in a similar way, but requires that the USB cable to the on-board debugger is unplugged. The board controller on the Wireless mainboard then makes the data available over USB (CDC) or an IP socket. Flow control is not available over the Mini Simplicity Connector.
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5. Radio
UG554: xG27 Dev Kit User’s Guide
Radio
5.1 RF Section
This section gives a short introduction to the RF section of the BRD2602A board.
The schematic of the RF section is shown in the figure below.
High Frequency
Crystal
3
U1B EFR32BG27
RF Cr ys t a l 9 HFXTAL_I
Supply
2
X1
4
38.4 MHz
VDCDC Filtering
L4 742692004
GND
1
2
1
10 HFXTAL_O
RF Ana l og Powe r 12 RFVDD
C11 100N
C12 120P
PA Powe r 15 PAVDD
L5 742692004
1
2
GND GND
C18 100N
C19 120P
RF I / O RF2G4_IO 14
Gr ound
RFVSS 13
2.4 GHz
Matching
Network
L1
L2
2N0
3N2
C2 1P6
Chip Antenna and Antenna Matching Network
CC1
L9 0R
18P
ANT1
1 IN
GND 2
4 GND GND 3
C4
2450AT18D0100
1P0
GND
GND GND
Figure 5.1. Schematic of the RF section
5.1.1 Description of the RF Matching The EFR32BG27 RF port impedance is matched to 50 Ohm: the RF2G4_IO pin is connected to a three-element impedance matching and harmonic filter circuitry and a dc blocking capacitor. The on-board ceramic antenna is also matched to 50 Ohm by its impedance matching components and connected to the EFR32BG27.
5.1.2 RF Section Power Supply On the BRD2602A, the supply for the radio (RFVDD) and the power amplifier (PAVDD) is connected to the on-chip dc-dc converter. By default, the dc-dc converter provides 1.8 V for the entire RF section (for details, see the schematic of the BRD2602A).
5.1.3 RF Matching Bill of Materials The Bill of Materials of the BRD2602A RF matching network is shown in the following table.
Table 5.1. Bill of Materials of the BRD2602A RF Matching Network
Component name L1 L2 C2 CC1
Value 2.0 nH 3.2 nH 1.6 pF 18 pF
Manufacturer Murata Murata Murata Murata
Part Number LQP03TN2N0C02D LQP03TN3N2C02D GRM0335C1H1R6WA01D GJM0335C1E180GB01D
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5.1.4 Antenna
The BRD2602A has an on-board ceramic antenna.
The land pattern for the antenna on the PCB layout was designed based on the recommendations of the antenna data sheet. Because there is a significant difference between the layout (practically the board size) of the BRD2602A and the antenna evaluation board, the applied antenna matching network deviates from the recommendation.
The values of the antenna matching network components were fine-tuned to match the antenna impedance close to 50 Ohm on the BRD2602A PCB. The resulting antenna impedance and reflection are shown in the figure below.
Figure 5.2. Fine-tuned Antenna Impedance (Blue Curve) and Reflection (Red Curve)
5.1.5 Antenna Matching Bill of Materials The Bill of Materials of the BRD2602A antenna matching network is shown in the following table.
Table 5.2. Bill of Materials of the BRD2602A Antenna Matching Network
Component name ANT1 L9 C5
Value —
0 Ohm 1.0 pF
Manufacturer Johanson — Murata
Part Number 2450AT18D0100
— GRM0335C1E1R0BA01D
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5.2 EMC Regulations for 2.4 GHz
UG554: xG27 Dev Kit User’s Guide
Radio
5.2.1 ETSI EN 300-328 Emission Limits for the 2400-2483.5 MHz Band
Based on ETSI EN 300-328, the allowed maximum fundamental power for the 2400-2483.5 MHz band is 20 dBm EIRP. For the unwanted emissions in the 1 GHz to 12.75 GHz domain the specified limit is -30 dBm EIRP.
5.2.2 FCC15.247 Emission Limits for the 2400-2483.5 MHz Band
FCC 15.247 allows conducted output power up to 1 Watt (30 dBm) in the 2400-2483.5 MHz band. For spurious emissions the limit is -20 dBc based on either conducted or radiated measurement, if the emission is not in a restricted band. The restricted bands are specified in FCC 15.205. In these bands the spurious emission levels must meet the levels set out in FCC 15.209. In the range from 960 MHz to the frequency of the 5th harmonic, it is defined as 0.5 mV/m at 3 m distance (equals to -41.2 dBm in EIRP).
If of operating in the 2400-2483.5 MHz band, the 2nd, 3rd, and 5th harmonics can fall into restricted bands, so for those the -41.2 dBm limit should be applied. For the 4th harmonic, the -20 dBc limit should be applied.
5.2.3 Applied Emission Limits The overall applied limits are shown in the table below. For the harmonics that fall into the FCC restricted bands, the FCC 15.209 limit is applied, and the ETSI EN 300-328 limit is applied for the rest.
Table 5.3. Applied Limits for Spurious Emissions
Harmonic 2nd 3rd 4th 5th
Frequency 4800~4967 MHz 7200~7450.5 MHz 9600~9934 MHz 12000~12417.5 MHz
Limit -41.2 dBm -41.2 dBm -30 dBm -41.2 dBm
5.3 Relaxation with Modulated Carrier
Depending on the applied modulation scheme and the Spectrum Analyzer settings specified by the relevant EMC regulations, the measured power levels are usually lower compared to the results with an unmodulated carrier. These differences have been measured and used as relaxation factors on the results of the radiated measurement performed with an unmodulated carrier. With this method, the radiated compliance with modulated transmission can be evaluated.
In this case, both the ETSI EN 300-328 and the FCC 15.247 regulations define the following Spectrum Analyzer settings for measuring the unwanted emissions above 1 GHz: · Detector: Average · RBW: 1 MHz
The table below shows the relative levels of the measured modulated signals compared to the unmodulated levels with the above Spectrum Analyzer settings in case of the supported modulation schemes.
Table 5.4. Measured Relaxation Factors for the Supported Modulation Schemes
Applied Modulation (Packet Length: 255 bytes)
2nd harmonic
3rd harmonic
4th harmonic
5th harmonic
BLE Coded PHY:
BLE Coded PHY:
BLE 1M PHY: 1 Mb/s
125 Kb/s (PRBS9) [dB] 500 Kb/s (PRBS9) [dB]
(PRBS9) [dB]
-2.7
-3.1
-3.3
-4.8
-5.2
-5.2
-5.5
-6.5
-6.7
-6.3
-6.5
-6.7
BLE 2M PHY: 2 Mb/s (PRBS9) [dB] -9.1 -10.7 -11.9 -11.4
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As it can be observed, the BLE 125 Kb/s coded modulation scheme has the lowest relaxation factors. These values will be used as the worst-case relaxation factors for the radiated measurements.
5.4 Radiated Power Measurements
The output power of the EFR32BG27 was set to 8 dBm. The board was supplied through its USB connector by connecting to a PC through a USB cable.
During the measurements, the board was rotated in three cuts; see the reference plane illustration in the figure below. The radiated powers of the fundamental and the harmonics were measured with horizontal and vertical reference antenna polarizations.
X
Z
Y
Figure 5.3. DUT Reference Planes
5.4.1 Maximum Radiated Power Measurement
The transceiver was operated in unmodulated carrier transmission mode, and the output power of the radio was set to 8 dBm. The results are shown in the table below.
The correction factors are applied based on the BLE 125 Kb/s coded modulation, showed in section 5.3 Relaxation with Modulated Carrier. The correction factors are larger for the rest of the supported modulation schemes; thus, the related calculated margins would be higher than those shown in the table below. Thus, the below margins can be considered as worst-case margins.
Table 5.5. Maximums of the Measured Radiated Powers of BRD2602A
Frequency (2440 MHz)
Measured Unmodulated EIRP
[dBm]
Orientation
BLE 125 Kb/s Coded Modulation
Correction Factor [dB]
Calculated Modulated EIRP
[dBm]
Modulated Margin [dB]
Fund
9.5
YZ/H
NA (0 is used)
7.3
22.7
2nd
-57.8
YZ/H
-2.7
-60.5
19.3
3rd
-46.3
YZ/H
-4.8
-51.1
9.9
4th
<-50*
—
-5.5
—
>20
5th
-49.9
YZ/V
-6.3
-56.2
15.0
* Signal level is below the Spectrum Analyzer noise floor.
Limit in EIRP [dBm] 30 -41.2 -41.2 -30 -41.2
As shown in the above table, the radiated power levels with modulation are far below the applied limits.
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5.4.2 Antenna Pattern Measurement The measured typical antenna patterns are shown in the figures below.
UG554: xG27 Dev Kit User’s Guide
Radio
Normalized Radiation Pattern [dB], XY cut
315° 270°
0° 0 -5 -10 -15 -20 -25 -30 -35
45° 90°
225°
135°
180°
Figure 5.4. Antenna Pattern – XY
Horizontal Vertical
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Normalized Radiation Pattern [dB], XZ cut
315° 270°
0° 0 -5 -10 -15 -20 -25 -30 -35
45° 90°
225°
135°
180°
Figure 5.5. Antenna Pattern – XZ
Horizontal Vertical
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Radio
Normalized Radiation Pattern [dB], YZ cut
315° 270°
0° 0 -5 -10 -15 -20 -25 -30 -35
45° 90°
225°
135°
180°
Figure 5.6. Antenna Pattern – YZ
Horizontal Vertical
5.5 EMC Compliance Recommendations
5.5.1 Recommendations for 2.4 GHz ETSI EN 300-328 Compliance As shown in the previous chapter, with the EFR32BG27 output power set to 8 dBm, the radiated power of the BRD2602A fundamental complies with the 20 dBm limit of the ETSI EN 300-328. The harmonic emissions are under the applied limits with margin.
5.5.2 Recommendations for 2.4 GHz FCC 15.247 Compliance As shown in the previous chapter, with the EFR32BG27 output power set to 8 dBm, the radiated power of the BRD2602A fundamental complies with the 30 dBm limit of the FCC 15.247. The harmonic emissions are under the applied limits with margin.
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Schematics, Assembly Drawings, and BOM
6. Schematics, Assembly Drawings, and BOM
Schematics, assembly drawings, and bill of materials (BOM) are available through Simplicity Studio when the kit documentation package has been installed. They are also available from the kit page on the Silicon Labs website: silabs.com.
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Kit Revision History
7. Kit Revision History
The kit revision can be found printed on the box label of the kit, as outlined in the figure below. The kit revision history is summarized in the table below.
EFR32BG27 Dev Kit
xG27-DK2602A
26-04-23
2317000360 A01
Kit Revision A01 A00
Released 26 April 2023 8 March 2023
Figure 7.1. Revision Info
Table 7.1. Kit Revision History
Description Updated board revision to BRD2602A Rev. A02, changed kit packaging. Initial kit revision.
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8. Board Revision History and Errata
UG554: xG27 Dev Kit User’s Guide
Board Revision History and Errata
8.1 Revision History The board revision can be found laser printed on the board, and the board revision history is summarized in the following table.
Table 8.1. Board Revision History
Board BRD2602A Rev. A02 BRD2602A Rev. A01 BRD2602A Rev. A00
Released 19 April 2023 11 November 2022 9 March 2022
Description Updated antenna matching network. Updated BG27 matching network. Initial version.
8.2 Errata There are no known errata at present.
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9. Document Revision History
Revision 1.0 June 2023 · Initial document version.
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Document Revision History
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