Boron BRN404X datasheet

Functional description

Overview

The Boron is a powerful LTE Cat M1 enabled development kit that supports cellular networks and Bluetooth LE (BLE). It is based on the Nordic nRF52840 and has built-in battery charging circuitry so it’s easy to connect a Li-Po and deploy your local network in minutes.

The Boron is great for connecting existing projects to the Particle Device Cloud where Wi-Fi is missing or unreliable.

Features

Features - BRN404X (Boron LTE)

  • u-blox SARA-R510S-01B LTE modem
  • LTE Cat M1 module
  • Support for United States, Canada, and Mexico only
  • 3GPP Release 14 LTE Cat M1
  • LTE Cat M1 bands: 2, 4, 5, 12, 13
  • Embedded Particle EtherSIM
  • Requires Device OS 4.0.0 LTS (or later)

Features - all models

  • Nordic Semiconductor nRF52840 SoC
    • ARM Cortex-M4F 32-bit processor @ 64MHz
    • 1MB flash, 256KB RAM
    • Bluetooth 5: 2 Mbps, 1 Mbps, 500 Kbps, 125 Kbps
    • Supports DSP instructions, HW accelerated Floating Point Unit (FPU) and encryption functions
    • Up to +8 dBm TX power (down to -20 dBm in 4 dB steps)
    • NFC-A tag
  • On-board additional 4MB SPI flash
  • 20 mixed signal GPIO (6 x Analog, 8 x PWM), UART, I2C, SPI
  • Micro USB 2.0 full speed (12 Mbps)
  • Integrated Li-Po charging and battery connector
  • JTAG (SWD) Connector
  • RGB status LED
  • Reset and Mode buttons
  • Dual SIM support: Nano 4FF and MFF2
  • On-board PCB antenna
  • U.FL connector for external antenna
  • Meets the Adafruit Feather specification in dimensions and pinout
  • FCC (United States) and ISED (Canada) certified
  • RoHS compliant (lead-free)

Model comparison

BRN404X BRN404 BRN402 BRN313 BRN310
Region NorAm NorAm NorAm Global Global
Technology LTE Cat M1 LTE Cat M1 LTE Cat M1 2G/3G 2G/3G
EtherSIM    
Supply Secure        
Lifecycle GA Deprecated Deprecated NRND NRND
  • EtherSIM devices generally have a larger number of carriers and more may be added in the future
  • NorAm: North America (United States, Canada, and Mexico)
  • Global 2G/3G devices not recommended in the United States due to the impending shutdown of 2G/3G networks
  • NRND: Not recommended for new designs
  • See the Carrier list for specific carrier and country compatibility
  • See the Supply secure FAQ for more information
  • See Lifestyle stages for more information

Device OS support

It is recommended that you use the latest version in the 4.x LTS release line with the BRN404X. The minimum required version is 4.0.0. You cannot use the BRN404X with Device OS 2.x LTS.

For information on upgrading Device OS, see Version information. For the latest version shipped from the factory, see Manufacturing firmware versions page. See also Long Term Support (LTS) releases.

Interfaces

Block diagram

Block Diagram

Power

USB PORT

The USB port is the easiest way to power up the Boron. Please make sure that the USB port is able to provide at least 500mA. Power from the USB is regulated down to 3.3V by a step-down regulator.

VUSB PIN

The pin is internally connected to the VBUS of the USB port. The nominal output should be around 4.5 to 5 VDC when the device is plugged into the USB port and 0 when not connected to a USB source. You can use this pin to power peripherals that operate at such voltages. Do not exceed the current rating of the USB port, which is nominally rated to 500mA.

LiPo

If you want to make your projects truly wireless, you can power the device with a single cell LiPo (3.7V). The Boron has an on board LiPo charger that will charge and power the device when USB source is plugged in, or power the device from the LiPo alone in the absence of the USB.

NOTE: Please pay attention to the polarity of the LiPo connector. Not all LiPo batteries follow the same polarity convention!

Li+ pin

This pin is internally connected to the positive terminal of the LiPo connector. You can connect a single cell LiPo/Lithium Ion or a DC supply source to this pin for powering the Boron. Remember that the input voltage range on this pin is 3.6 to 4.2 VDC.

3V3 PIN

This pin is the output of the on board 3.3V step-down switching regulator. The regulator is rated at 1000mA max. When using this pin to power other devices or peripherals remember to budget in the current requirement of the Boron first. Unlike the Photon, this pin CANNOT be used to power the Boron.

EN pin

The EN pin is not a power pin, per se, but it controls the 3V3 and cellular modem power via a load switch (XC8107, U2). The EN pin is pulled high by a 100K resistor to PMIC_SYS (3.8V), which is powered by VUSB, the micro USB connector, or the LiPo battery. Because the pull-up can result in voltages above 3.3V you should never directly connect EN to a 3.3V GPIO pin. Instead, you should only pull EN low, such as by using an N-channel MOSFET or other open-collector transistor.

The EN pin can force the device into a deep power-down state where it uses very little power. It also can used to assure that the device is completely reset, similar to unplugging it, with one caveat:

If using the EN pin to deeply reset the device, you must be careful not to allow leakage current back into the nRF52 MCU by GPIO or by pull-ups to 3V3. If you only power external devices by 3V3 you won't run into this, as 3V3 is de-powered when EN is low.

However, if you have circuitry that is powered by a separate, external power supply, you must be careful. An externally powered circuit that drives a nRF52 GPIO high when EN is low can provide enough current to keep the nRF52 from powering down and resetting. Likewise, a pull-up to an external power supply can do the same thing. Be sure that in no circumstances can power by supplied to the nRF52 when 3V3 is de-powered.

See the power supply schematic, below, for more information.


Antenna

There are two radios on the Boron. A BLE radio (nRF52840) and a cellular radio (u-blox). For the cellular radio, we have provided a u.FL connector to plug in the cellular antenna. This is required if you wish to use the cellular connectivity.

There are two options for the BLE antenna on the Boron. It comes with an on-board PCB antenna which is selected by default in the device OS and a u.FL connector if you wish to connect an external antenna. If you wish to use the external antenna, you'll need to issue an appropriate command in the firmware.

FCC approved antennas

Certified cellular antenna

The following antenna is included in single-unit packages that include an antenna.

Antenna SKU Details Links
Wide band LTE-CAT M1 cell antenna, [x1] PARANTC41EA B404X, BRN404X, and E404X Datasheet
Wide band LTE-CAT M1 cell antenna, [x50] PARANTC41TY B404X, BRN404X, and E404X Datasheet

General antenna parameters:

Parameter Value Unit
Antenna Type Dipole
Radiation Properties Omnidirectional
Maximum Input Power 5 watts
Polarization Linear
Impedance 50 ohms

Antenna parameters in frequency ranges:

Parameter 698 MHz - 894 MHz 1700 MHz - 2690 MHz Unit
Peak Gain 2.46 3.86 dBi
Efficiency 65.46 54.95 %
Average Gain 1 0.98

Antenna parameters in specific frequency bands:

Parameter 698 MHz 894 MHz 1700 MHz 2170 MHz 2690 MHz Unit
Max VSWR 1.6 1.8 1.7 2.8 2.5
Max Return Loss -12 -10 -11 -6 -7 dB

Mechanical:

Parameter Value Unit
Dimensions 122.1 x 12.8 x 0.2 mm
Material Flexible polymer
Connector and cable U.FL and 1.13mm mini coax
Cable length 183 mm

Environmental:

Parameter Value
Operating temperature -40°C to 85°C
Storage temperature -40°C to 85°C
ROHS Compliant

Particle devices are certified for use only with the designated antenna specified above. The use of alternative antennas with our modules could necessitate a recertification process. To fully understand the potential consequences of using a non-certified antenna, Particle strongly advises seeking consultation with a qualified RF expert.

Alternate cellular antenna

Additionally, the following antenna is certified as an alternative antenna.

Antenna SKU Details Links
Taoglas Cellular Flex Antenna 2G/3G/LTE 5dBi, [x1] ANT-FLXU Boron and Electron/E-Series LTE M1 Datasheet | Retail Store
Taoglas Cellular Flex Antenna 2G/3G/LTE 5dBi, [x50] ANT-FLXU-50 Boron and Electron/E-Series LTE M1 Datasheet

General antenna parameters:

Parameter Value Unit
Antenna Type Dipole
Radiation Properties Omnidirectional
Maximum Input Power 5 watts
Polarization Linear
Impedance 50 ohms

Antenna parameters in frequency ranges:

Parameter 700/850/900 1700/1800/1900 2100 2400 2600 Unit
Peak Gain 1 3.5 5 5 4.5 dBi
Efficiency 50 78 65 75 75 %
Average Gain -3 -2 -2.5 -2 -2 dB

Antenna parameters in specific frequency bands:

Parameter 700/850/900 1700/1800/1900 2100 2400 2600 Unit
Max VSWR 2.0 1.8 1.7 1.7 2.3
Max Return Loss -10 -11 -12 -12 -8 dB

Mechanical:

Parameter Value Unit
Dimensions 96 x 21 x 0.2 mm
Material Flexible polymer
Connector and cable U.FL and 1.37mm mini coax
Cable length 150 mm

Environmental:

Parameter Value
Operating temperature -40°C to 85°C
Storage temperature -40°C to 85°C
ROHS Compliant

Certified BLE antenna

The Boron 404X contains an onboard chip antenna for Bluetooth LE (BLE). You can optionally use an external 2.4 GHz BLE antenna.

Antenna SKU Links
Built-in chip antenna Datasheet
Particle Wi-Fi Antenna 2.4GHz, [x1] ANT-FLXV2 Datasheet | Retail Store
Particle Wi-Fi Antenna 2.4GHz, [x50] ANT-FLXV2-50 Datasheet
Frequency Antenna Type Manufacturer MFG. Part # Gain
2400-2500 MHz Chip Antenna ACX AT5020-E3R0HBA 0dBi peak
2400-2500 MHz PCB Antenna Particle ANT-FLXV2 2.0dBi peak

Built-in chip antenna

General antenna parameters:

Parameter Value Unit
Manufacturer ACX
Model AT5020-E3R0HBA
Antenna Type Chip
Impedance 50 ohms
Peak Gain 0 dBi
Average Gain -1.5 dBi
Max VSWR 2

Particle external antenna ANT-FLXV2 General antenna parameters:

Parameter Value Unit
Antenna Type Dipole
Radiation Properties Omnidirectional
Polarization Vertical
Impedance 50 ohms
Peak Gain 2.0 dBi
Max VSWR < 2.0

Mechanical:

Parameter Value Unit
Dimensions 45.1 x 7.4 x 1.0 mm
Material PCB
Connector U.FL (IPEX)
Cable Mini-coax 1.13mm
Cable length 120 mm

Environmental:

Parameter Value
Operating temperature -20°C to 75°C
Storage temperature -20°C to 75°C
ROHS Compliant

Certified NFC antenna

Antenna SKU Links
Particle NFC Antenna, [x1] ANT-NFC Datasheet | Retail Store

General antenna parameters:

Parameter Value Unit
Frequency 13.56 MHz
Communication Distance (max) 52 mm

Mechanical:

Parameter Value Unit
Dimensions 35 x 35 mm
Connector and cable U.FL and 1.13mm mini coax
Cable length 100 mm

Environmental:

Parameter Value
Operating temperature -20°C to 85°C
Storage temperature -20°C to 85°C
ROHS Compliant

Peripherals and GPIO

Peripheral Type Qty Input(I) / Output(O)
Digital 20 I/O
Analog (ADC) 6 I
UART 1 I/O
SPI 1 I/O
I2C 2 I/O
USB 1 I/O
PWM 8 O

Note: All GPIOs are only rated at 3.3VDC max.

SWD

The Boron has a dedicated 10 pin debug connector that exposes the SWD interface of the nRF52840. This interface can be used to debug your code or reprogram your Boron bootloader, device OS, or the user firmware using any standard SWD tools including our Gen 3 Debugger.

Memory map

nRF52840 flash layout overview

  • Bootloader (48KB, @0xF4000)
  • User Application
    • 256KB @ 0xB4000 (Device OS 3.1 and later)
    • 128KB @ 0xD4000 (Device OS 3.0 and earlier)
  • System (656KB, @0x30000)
  • SoftDevice (192KB)

External SPI flash layout overview (dfu offset: 0x80000000)

  • OTA (1500KB, @0x00289000)
  • Reserved (420KB, @0x00220000)
  • FAC (128KB, @0x00200000)
  • LittleFS (2M, @0x00000000)

Pins and button definitions

Pin markings

Pinout diagram

Pinout

You can download a high resolution PDF version of the pin out here.

Pin description

Pin Description
Li+ This pin is internally connected to the positive terminal of the LiPo battery connector.
VUSB This pin is internally connected to the USB (+ve) supply.
3V3 This pin is the output of the on-board 3.3V regulator.
GND System ground pin.
EN Device enable pin is internally pulled-up. To disable the device, connect this pin to GND.
RST Active-low system reset input. This pin is internally pulled-up.
MD This pin is internally connected to the MODE button. The MODE function is active-low.
RX Primarily used as UART RX, but can also be used as a digital GPIO.
TX Primarily used as UART TX, but can also be used as a digital GPIO.
SDA Primarily used as data pin for I2C, but can also be used as a digital GPIO.
SCL Primarily used as clock pin for I2C, but can also be used as a digital GPIO.
MO,MI,SCK These are the SPI interface pins, but can also be used as a digital GPIO.
D2-D8 These are generic GPIO pins. D2-D8 are PWM-able.
A0-A5 These are analog input pins that can also act as standard digital GPIO. A0-A5 are PWM-able.

GPIO and port listing

Pin Name MCU
A0 / D19 ADC0       P0.03
A1 / D18 ADC1       P0.04
A2 / D17 ADC2       P0.28
A3 / D16 ADC3       P0.29
A4 / D15 ADC4       P0.30
A5 / D14 ADC5   SPI (SS)   P0.31
D0   Wire (SDA)     P0.26
D1   Wire (SCL)     P0.27
D2     SPI1 (SCK) Serial1 RTS P1.01
D3     SPI1 (MOSI) Serial1 CTS P1.02
D4     SPI1 (MISO)   P1.08
D5         P1.10
D6         P1.11
D7         P1.12
D8 / WKP         P1.03
MISO / D11     SPI (MISO)   P1.14
MOSI / D12     SPI (MOSI)   P1.13
RX / D10       Serial1 RX P0.08
SCK / D13     SPI (SCK)   P1.15
TX / D09       Serial1 TX P0.06

ADC (analog to digital converter)

The Boron supports 6 ADC inputs.

Pin Name Description Interface MCU
A0 / D19 A0 Analog in, GPIO, PWM ADC0 P0.03
A1 / D18 A1 Analog in, GPIO, PWM ADC1 P0.04
A2 / D17 A2 Analog in, GPIO, PWM ADC2 P0.28
A3 / D16 A3 Analog in, GPIO, PWM ADC3 P0.29
A4 / D15 A4 Analog in, GPIO, PWM ADC4 P0.30
A5 / D14 A5 Analog in, GPIO, PWM, SPI SS ADC5 P0.31
  • ADC inputs are single-ended and limited to 0 to 3.3V
  • Resolution is 12 bits

UART serial

The Boron supports one UART serial interface.

Pin Name Description Interface MCU
D2 SPI1 SCK, Serial1 RTS, GPIO, PWM Serial1 RTS P1.01
D3 SPI1 MOSI, Serial1 CTS, PWM, GPIO Serial1 CTS P1.02
RX / D10 Serial RX, GPIO Serial1 RX P0.08
TX / D09 Serial TX, GPIO Serial1 TX P0.06
  • The UART pins are 3.3V and must not be connected directly to a RS-232C port or to a 5V TTL serial port
  • Hardware flow control is optional; if not used then the RTS and CTS pins can be used as regular GPIO
  • You cannot use hardware flow control and Ethernet at the same time.

SPI

The Boron supports two SPI (serial peripheral interconnect) ports.

Pin Name Description Interface MCU
A5 / D14 A5 Analog in, GPIO, PWM, SPI SS SPI (SS) P0.31
D2 SPI1 SCK, Serial1 RTS, GPIO, PWM SPI1 (SCK) P1.01
D3 SPI1 MOSI, Serial1 CTS, PWM, GPIO SPI1 (MOSI) P1.02
D4 SPI1 MISO, PWM, GPIO SPI1 (MISO) P1.08
MISO / D11 SPI MISO, GPIO SPI (MISO) P1.14
MOSI / D12 SPI MOSI, GPIO SPI (MOSI) P1.13
SCK / D13 SPI SCK, GPIO SPI (SCK) P1.15
  • The SPI port is 3.3V and must not be connected directly to devices that drive MISO at 5V
  • If not using a SPI port, its pins can be used as GPIO
  • Any pins can be used as the SPI chip select
  • Multiple devices can generally share a single SPI port
  • You cannot use SPI1 and Ethernet at the same time.

I2C

The Boron supports one I2C (two-wire serial interface) port.

Pin Name Description Interface MCU
D0 I2C SDA, GPIO Wire (SDA) P0.26
D1 I2C SCL, GPIO Wire (SCL) P0.27
  • The I2C port is 3.3V and must not be connected directly a 5V I2C bus
  • Maximum bus speed is 400 kHz
  • External pull-up resistors are recommended for I2C as the internal pull-up is 13K.
  • If not using I2C, pins D0 and D1 can be used as GPIO or analog input.

PWM

The Boron supports PWM (pulse-width modulation) on the following pins:

Pin Name Description Timer MCU
A0 / D19 A0 Analog in, GPIO, PWM PWM2 P0.03
A1 / D18 A1 Analog in, GPIO, PWM PWM2 P0.04
A2 / D17 A2 Analog in, GPIO, PWM PWM2 P0.28
A3 / D16 A3 Analog in, GPIO, PWM PWM2 P0.29
A4 / D15 A4 Analog in, GPIO, PWM PWM3 P0.30
A5 / D14 A5 Analog in, GPIO, PWM, SPI SS PWM3 P0.31
D2 SPI1 SCK, Serial1 RTS, GPIO, PWM PWM3 P1.01
D3 SPI1 MOSI, Serial1 CTS, PWM, GPIO PWM3 P1.02
D4 SPI1 MISO, PWM, GPIO PWM1 P1.08
D5 PWM, GPIO PWM1 P1.10
D6 PWM, GPIO PWM1 P1.11
D7 PWM, GPIO PWM0 P1.12
D8 / WKP GPIO, PWM PWM1 P1.03
  • PWM that share the same timer (PMW2 for example) must share the same frequency but can have different duty cycles.
  • Pin D7 (PWM0) share a timer with the RGB LED and you should not change its frequency but it can have a different duty cycle.

Complete module pin details

1 RST

Details
Pin Number1
Pin NameRST
DescriptionHardware reset. Pull low to reset; can leave unconnected in normal operation.
MCU PinP0.18

2 3V3

Details
Pin Number2
Pin Name3V3
DescriptionRegulated 3.3V DC output, maximum load 1000 mA

3 MODE

Details
Pin Number3
Pin NameMODE
Pin Alternate NameD20
DescriptionMODE button, has internal pull-up
MCU PinP0.11

4 GND

Details
Pin Number4
Pin NameGND
DescriptionGround.

5 A0

Details
Pin Number5
Pin NameA0
Pin Alternate NameD19
DescriptionA0 Analog in, GPIO, PWM
Supports digitalReadYes
Supports digitalWriteYes
Supports analogReadYes
Supports analogWrite (PWM)Yes
Supports toneA0, A1, A2, and A3 must have the same frequency.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP0.03

6 A1

Details
Pin Number6
Pin NameA1
Pin Alternate NameD18
DescriptionA1 Analog in, GPIO, PWM
Supports digitalReadYes
Supports digitalWriteYes
Supports analogReadYes
Supports analogWrite (PWM)Yes
Supports toneA0, A1, A2, and A3 must have the same frequency.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP0.04

7 A2

Details
Pin Number7
Pin NameA2
Pin Alternate NameD17
DescriptionA2 Analog in, GPIO, PWM
Supports digitalReadYes
Supports digitalWriteYes
Supports analogReadYes
Supports analogWrite (PWM)Yes
Supports toneA0, A1, A2, and A3 must have the same frequency.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP0.28

8 A3

Details
Pin Number8
Pin NameA3
Pin Alternate NameD16
DescriptionA3 Analog in, GPIO, PWM
Supports digitalReadYes
Supports digitalWriteYes
Supports analogReadYes
Supports analogWrite (PWM)Yes
Supports toneA0, A1, A2, and A3 must have the same frequency.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP0.29

9 A4

Details
Pin Number9
Pin NameA4
Pin Alternate NameD15
DescriptionA4 Analog in, GPIO, PWM
Supports digitalReadYes
Supports digitalWriteYes
Supports analogReadYes
Supports analogWrite (PWM)Yes
Supports toneA4, A5, D2, and D3 must have the same frequency.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP0.30

10 A5

Details
Pin Number10
Pin NameA5
Pin Alternate NameD14
DescriptionA5 Analog in, GPIO, PWM, SPI SS
Supports digitalReadYes
Supports digitalWriteYes
Supports analogReadYes
Supports analogWrite (PWM)Yes
Supports toneA4, A5, D2, and D3 must have the same frequency.
SPI interfaceSS. Use SPI object. This is only the default SS/CS pin, you can use any GPIO instead.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP0.31

11 SCK

Details
Pin Number11
Pin NameSCK
Pin Alternate NameD13
DescriptionSPI SCK, GPIO
Supports digitalReadYes
Supports digitalWriteYes
SPI interfaceSCK. Use SPI object.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP1.15

12 MOSI

Details
Pin Number12
Pin NameMOSI
Pin Alternate NameD12
DescriptionSPI MOSI, GPIO
Supports digitalReadYes
Supports digitalWriteYes
SPI interfaceMOSI. Use SPI object.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP1.13

13 MISO

Details
Pin Number13
Pin NameMISO
Pin Alternate NameD11
DescriptionSPI MISO, GPIO
Supports digitalReadYes
Supports digitalWriteYes
SPI interfaceMISO. Use SPI object.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP1.14

14 RX

Details
Pin Number14
Pin NameRX
Pin Alternate NameD10
DescriptionSerial RX, GPIO
Supports digitalReadYes
Supports digitalWriteYes
UART serialRX. Use Serial1 object.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP0.08

15 TX

Details
Pin Number15
Pin NameTX
Pin Alternate NameD09
DescriptionSerial TX, GPIO
Supports digitalReadYes
Supports digitalWriteYes
UART serialTX. Use Serial1 object.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP0.06

16 D0

Details
Pin Number16
Pin NameD0
DescriptionI2C SDA, GPIO
Supports digitalReadYes
Supports digitalWriteYes
I2C interfaceSDA. Use Wire object.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP0.26

17 D1

Details
Pin Number17
Pin NameD1
DescriptionI2C SCL, GPIO
Supports digitalReadYes
Supports digitalWriteYes
I2C interfaceSCL. Use Wire object.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP0.27

18 D2

Details
Pin Number18
Pin NameD2
DescriptionSPI1 SCK, Serial1 RTS, GPIO, PWM
Supports digitalReadYes
Supports digitalWriteYes
Supports analogWrite (PWM)Yes
Supports toneA4, A5, D2, and D3 must have the same frequency.
UART serialRTS. Use Serial1 object.
SPI interfaceSCK. Use SPI1 object.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP1.01

19 D3

Details
Pin Number19
Pin NameD3
DescriptionSPI1 MOSI, Serial1 CTS, PWM, GPIO
Supports digitalReadYes
Supports digitalWriteYes
Supports analogWrite (PWM)Yes
Supports toneA4, A5, D2, and D3 must have the same frequency.
UART serialCTS. Use Serial1 object.
SPI interfaceMOSI. Use SPI1 object.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP1.02

20 D4

Details
Pin Number20
Pin NameD4
DescriptionSPI1 MISO, PWM, GPIO
Supports digitalReadYes
Supports digitalWriteYes
Supports analogWrite (PWM)Yes
Supports toneD4, D5, D6, and D7 must have the same frequency.
SPI interfaceMISO. Use SPI1 object.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP1.08

21 D5

Details
Pin Number21
Pin NameD5
DescriptionPWM, GPIO
Supports digitalReadYes
Supports digitalWriteYes
Supports analogWrite (PWM)Yes
Supports toneD4, D5, D6, and D7 must have the same frequency.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP1.10

22 D6

Details
Pin Number22
Pin NameD6
DescriptionPWM, GPIO
Supports digitalReadYes
Supports digitalWriteYes
Supports analogWrite (PWM)Yes
Supports toneD4, D5, D6, and D7 must have the same frequency.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP1.11

23 D7

Details
Pin Number23
Pin NameD7
DescriptionPWM, GPIO
Supports digitalReadYes
Supports digitalWriteYes
Supports analogWrite (PWM)PWM is shared with the RGB LED, you can specify a different duty cycle but should not change the frequency.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP1.12

24 D8

Details
Pin Number24
Pin NameD8
Pin Alternate NameWKP
DescriptionGPIO, PWM
Supports digitalReadYes
Supports digitalWriteYes
Supports analogWrite (PWM)Yes
Supports toneD4, D5, D6, and D7 must have the same frequency.
Supports attachInterruptYes. You can only have 8 active interrupt pins.
Internal pull resistance13K
MCU PinP1.03

25 VUSB

Details
Pin Number25
Pin NameVUSB
DescriptionPower out (when powered by USB) 5 VDC at 1A maximum. Power in with limitations.
Input is 5V TolerantYes

26 EN

Details
Pin Number26
Pin NameEN
DescriptionPower supply enable. Connect to GND to power down. Has internal weak (100K) pull-up.

27 LI+

Details
Pin Number27
Pin NameLI+
DescriptionConnected to JST PH LiPo battery connector. 3.7V in or out.

LED status

System RGB LED

For a detailed explanation of different color codes of the RGB system LED, please take a look here.

Charge status LED

State Description
ON Charging in progress
OFF Charging complete
Blink at 1Hz Fault condition[1]
Rapid blinking Battery disconnected[2]

Notes:

[1] A fault condition can occur due to several reasons, for example, battery over/under voltage, temperature fault or safety timer fault. You can find the root cause by reading the fault register of the power management IC in firmware.

[2] You can stop this behavior by either plugging in the LiPo battery or by disabling charging using firmware command: PMIC().disableCharging();.

Technical specifications

Absolute maximum ratings [1]

Parameter Symbol Min Typ Max Unit
Supply Input Voltage VIN-MAX +6.2 V
Battery Input Voltage VLiPo +6.5 V
Supply Output Current I3V3-MAX-L 1000 mA
Storage Temperature Tstg -30 +75 °C
ESD Susceptibility HBM (Human Body Mode) VESD 1 kV

[1] Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

Parameter Symbol Min Typ Max Unit
LiPo Battery Voltage VLiPo +3.3 +4.4 V
Supply Input Voltage V3V3 +3.0 +3.3 +3.6 V
Supply Output Voltage V3V3 +3.3 V
Operating Temperature Top -20 +60 °C
Humidity Range Non condensing, relative humidity 95 %

Power consumption (Boron LTE)

Values are from BRN404/BRN402. Actual operating current with cellular using the R510 modem may vary but should be similar.

Parameter Symbol Min Typ Peak Unit
Peak Current ILi+ pk 120 490 mA
Operating Current (uC on, peripherals and radio disabled) Iidle 3.89 3.90 3.92 mA
Operating Current (uC on, cellular on but not connected) Icell_idle 5.78 16.9 mA
Operating Current (uC on, cellular connecting to tower) Icell_conn_twr 14.7 58.9 178 mA
Operating Current (uC on, cellular connecting to cloud) Icell_conn_cloud 14.6 53.4 207 mA
Operating Current (uC on, cellular connected but idle) Icell_cloud_idle 17.9 108 mA
Operating Current (uC on, cellular connected and transmitting) Icell_cloud_tx 63.9 184 mA
STOP mode sleep, GPIO wake-up Istop_gpio 565 575 590 uA
STOP mode sleep, analog wake-up Istop_analog 565 577 593 uA
STOP mode sleep, RTC wake-up Istop_intrtc 568 584 602 uA
STOP mode sleep, BLE wake-up, advertising Istop_ble_adv 91.6 885 2210 uA
STOP mode sleep, BLE wake-up, connected Istop_ble_conn 486 866 1440 uA
STOP mode sleep, serial wake-up Istop_usart 569 587 612 uA
STOP mode sleep, cellular wake-up Istop_cell 12.2 104 mA
ULP mode sleep, GPIO wake-up Iulp_gpio 127 137 uA
ULP mode sleep, analog wake-up Iulp_analog 130 141 uA
ULP mode sleep, RTC wake-up Iulp_intrtc 128 138 uA
ULP mode sleep, BLE wake-up, advertising Iulp_ble_adv 442 2120 uA
ULP mode sleep, BLE wake-up, connected Iulp_ble_conn 438 1050 uA
ULP mode sleep, serial wake-up Iulp_usart 568 584 601 uA
ULP mode sleep, cellular wake-up Iulp_cell 14.2 112 mA
HIBERNATE mode sleep, GPIO wake-up Ihib_gpio 98.7 106 118 uA
HIBERNATE mode sleep, analog wake-up Ihib_analog 99.4 106 120 uA
Power disabled (EN pin = LOW) Idisable 70 75 uA

1The min, and particularly peak, values may consist of very short transients. The typical (typ) values are the best indicator of overall power consumption over time. The peak values indicate the absolute minimum capacity of the power supply necessary, not overall consumption.


Radio specifications

Boron has two radio modules, the nRF52 MCU BLE radio, and a cellular module, depending on the model.

Nordic Semiconductor nRF52840 for BLE

Feature Description
Feature Bluetooth LE 5
Operating Frequencies 2360 to 2500 MHz
Output Power Programmable -20dBm to +8dBm
PLL channel spacing 1 MHz
On the air data rate 125 to 2000 kbps

Nordic Semiconductor nRF52840 for NFC tag

Feature Description
Feature NFC Tag-A
Frequency 13.56 MHz

u-blox SARA-R510S-01B

Parameter Value FCC Certified
Protocol stack 3GPP Release 13 LTE Cat M1
3GPP Release 14 LTE Cat M11
RAT LTE Cat M1 Half-Duplex
LTE FDD Bands Band 71 (600 MHz)  
Band 12 (700 MHz)
Band 28 (700 MHz)  
Band 85 (700 MHz)  
Band 13 (750 MHz)
Band 20 (800 MHz)  
Band 5 (850 MHz)
Band 18 (850 MHz)  
Band 19 (850 MHz)  
Band 26 (850 MHz)  
Band 8 (900 MHz)  
Band 4 (1700 MHz)  
Band 3 (1800 MHz)  
Band 2 (1900 MHz)
Band 25 (1900 MHz)  
Band 1 (2100 MHz)  
Power class Class 3 (23 dBm)  
Cellular data rate up to 1200 kbit/s UL
up to 375 kbit/s DL
  • LTE Cat M1 for United States, Canada, and Mexico.
  • FCC Certification in the United States only tests bands in use in the United States.
  • Bands not listed as certified are disabled in the Device OS operating system and cannot be enabled from user firmware.
  • Particle LTE Cat M1 devices are not certified for use in Europe or other countries that follow EU certification requirements.
  • 13GPP Release 14 LTE Cat M1: Coverage Enhancement Mode B, Uplink TBS of 2984b

I/O characteristics

These specifications are based on the nRF52840 datasheet.

Parameter Symbol Conditions Min Typ Max Unit
Input high voltage VIH 0.7*3.3 -- 3.3 V
Input low voltage VIL 0 0.3*3.3 V
Current at GND+0.4 V, output set low, high drive IOL,HDL V3V3 >= 2.7V 6 10 15 mA
Current at V3V3-0.4 V, output set high, high drive IOH,HDH V3V3 >= 2.7V 6 9 14 mA
Current at GND+0.4 V, output set low, standard drive IOL,SD V3V3 >= 2.7V 1 2 4 mA
Current at V3V3-0.4 V, output set high, standard drive IOH,SD V3V3 >= 2.7V 1 2 4 mA
Pull-up resistance RPU 11 13 16
Pull-down resistance RPD 11 13 16

GPIO default to standard drive (2mA) but can be reconfigured to high drive (9mA) in Device OS 2.0.0 and later using the pinSetDriveStrength() function.

Mechanical specifications

Dimensions and weight

  • Weight = 10 grams

3D models

3D models of the Boron are available in the hardware-libraries Github in formats including step, iges, stl, and f3d.

The 3D model for the BRN404X is the same as the other Borons, as the cellular modem module is the same size.

Mating connectors

The Boron uses two single row 0.1" pitch male header pins. One of them is 16 pin while the other is 12 pin. It can be mounted with matching 0.1" pitch female headers with a typical height of 0.335" (8.5mm). When you search for parts like these it can be difficult to navigate the thousands of parts available online so here are a few good choices for the Boron:

Description MFG MFG Part Number
16-pin 0.1" (2.54mm) Female Header Sullins PPTC161LFBN-RC
16-pin 0.1" (2.54mm) Female Header TE 6-535541-4
12-pin 0.1" (2.54mm) Female Header Sullins PPTC121LFBN-RC
12-pin 0.1" (2.54mm) Female Header TE 6-534237-0

The Boron can be directly soldered onto the PCB or be mounted with the above mentioned female headers.

Schematic

The complete schematic and board files are open source and available on Particle's GitHub repository here.

Power

Power Schematic

nRF52840

nRF52 Schematic

u-blox

u-blox Schematic

SIM

SIM Schematic

SPI Flash

SPI Flash

Fuel gauge

Fuel Gauge

Interfaces

Interfaces

Assembly

Water soluble flux

When attaching a Boron to your base board, we recommend using a socket. As there are components on the bottom side of the Boron there is no version available with castellated holes, solder pads, or similar techniques for direct surface mounting.

The pin headers on the bottom of the Boron are not intended to be reflowed using paste-in-hole.

If you decide to wave solder or hand-solder the Boron directly to your base board, water soluble flux should not be used. There are components within the Boron module that are moisture-sensitive, and wash water can get trapped under the RF shields, causing damage.

Use no-clean flux instead if you must solder the Boron module.

Conformal coatings

Boron modules should not use a conformal coating to protect the module from water. Some components on the module cannot be coated and would need to be masked off during coating. This will make the coating process difficult to implement and test.

Furthermore, the buttons cannot be protected by using a coating. Using an enclosure that protects both your base board and the Boron module as a single waterproof assembly is recommended instead.

Country compatibility

Country Model Technologies Carriers
Canada BRN404X M1 Bell Mobility, Rogers Wireless, Telus
Mexico BRN404X M1 AT&T, Telcel
United States BRN404X M1 AT&T, T-Mobile (USA), Verizon7

Ordering information

Borons are available from store.particle.io.

SKU Description Region Modem EtherSIM Lifecycle Replacement
BRN404X Boron LTE CAT-M1 (NorAm), [x1] NORAM R510 GA
BRN404XKIT Boron LTE CAT-M1 (NorAm, EtherSIM), Starter Kit [x1] NORAM R510 GA
BRN404XTRAY50 Boron LTE CAT-M1 (NorAm), Tray [x50] NORAM R510 GA

Qualification and approvals

BORON LTE (Cat M1)

  • Model Number: BRN404X
  • RoHS
  • CE
  • PTCRB
  • FCC ID: 2AEMI-BRN404X
  • ISED: 20127-BRN404X

Product handling

ESD precautions

The Boron contains highly sensitive electronic circuitry and is an Electrostatic Sensitive Device (ESD). Handling Boron without proper ESD protection may destroy or damage it permanently. Proper ESD handling and packaging procedures must be applied throughout the processing, handling and operation of any application that incorporates Boron. ESD precautions should be implemented on the application board where the Boron is mounted. Failure to observe these precautions can result in severe damage to the Boron!

Connectors

There are four connectors on the Boron that will get damaged with improper usage. The JST connector on the circuit board, where you plug in the LiPo battery, is very durable but the connector on the battery itself is not. When unplugging the battery, take extra precaution to NOT pull the connector using the wires, but instead hold the plug at its base to avoid putting stress on the wires. This can be tricky with bare hands - nose pliers are your friend here.

The micro B USB connector on the Boron is soldered on the PCB with large surface pads as well as couple of through hole anchor points. Despite this reinforcement, it is very easy to rip out the connector if too much stress is put on in the vertical direction.

The U.FL antenna connector is not designed to be constantly plugged and unplugged. The antenna pin is static sensitive and you can destroy the radio with improper handling. A tiny dab of glue (epoxy, rubber cement, liquid tape or hot glue) on the connector can be used securely hold the plug in place.

The 10 pin SWD connector provides an easy in-system debugging access to the device. The pins on the connector can easily be damaged if the mating connector cable is inserted improperly. If you are trying to debug the device, you probably are not in a good mood to begin with. The last thing you want is to render the connector useless. Be nice, and be gentle on the connector. Good luck with the debugging!

Breadboarding

The breadboard provided with the Boron is specifically designed to require low insertion force. This makes it easy to plug the Boron in and out of the breadboard. If you end up using a different breadboard, remember that it may require more force. In this case, always remember to pinch-hold your precious Boron by the sides (along the header pins) when plugging-unplugging and not by the USB connector (don't be this person).

Default settings

The Boron comes preprogrammed with a bootloader and a user application called Tinker. This application works with an iOS and Android app also named Tinker that allows you to very easily toggle digital pins, take analog and digital readings and drive variable PWM outputs.

The bootloader allows you to easily update the user application via several different methods, USB, OTA, Serial Y-Modem, and also internally via the Factory Reset procedure. All of these methods have multiple tools associated with them as well.

FCC ISED CE warnings and end product labeling requirements

Federal Communication Commission Interference Statement This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one of the following measures:

  • Reorient or relocate the receiving antenna.
  • Increase the separation between the equipment and receiver.
  • Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
  • Consult the dealer or an experienced radio/TV technician for help.

FCC Caution: Any changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate this equipment. This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:

  1. This device may not cause harmful interference, and
  2. This device must accept any interference received, including interference that may cause undesired operation.

FCC Radiation Exposure Statement: This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. This transmitter module must not be co-located or operating in conjunction with any other antenna or transmitter. This End equipment should be installed and operated with a minimum distance of 20 centimeters between the radiator and your body.

IMPORTANT NOTE: In the event that these conditions can not be met (for example certain laptop configurations or co-location with another transmitter), then the FCC authorization is no longer considered valid and the FCC ID can not be used on the final product. In these circumstances, the OEM integrator will be responsible for re-evaluating the end product (including the transmitter) and obtaining a separate FCC authorization.

End Product Labeling The final end product must be labeled in a visible area with the following:

  • Contains FCC ID: 2AEMI-BRN404X

Manual Information to the End User The OEM integrator has to be aware not to provide information to the end user regarding how to install or remove this RF module in the user’s manual of the end product which integrates this module.


Canada Statement This device complies with Industry Canada’s licence-exempt RSSs. Operation is subject to the following two conditions:

  1. This device may not cause interference; and
  2. This device must accept any interference, including interference that may cause undesired operation of the device.

Le présent appareil est conforme aux CNR d’Industrie Canada applicables aux appareils radio exempts de licence.

L’exploitation est autorisée aux deux conditions suivantes:

  1. l’appareil ne doit pas produire de brouillage;
  2. l’utilisateur de l’appareil doit accepter tout brouillage radioélectrique subi, même si le brouillage est susceptible d’en compromettre le fonctionnement.

Caution Exposure: This device meets the exemption from the routine evaluation limits in section 2.5 of RSS102 and users can obtain Canadian information on RF exposure and compliance. Le dispositif répond à l'exemption des limites d'évaluation de routine dans la section 2.5 de RSS102 et les utilisateurs peuvent obtenir des renseignements canadiens sur l'exposition aux RF et le respect.

The final end product must be labelled in a visible area with the following: The Industry Canada certification label of a module shall be clearly visible at all times when installed in the host device, otherwise the host device must be labelled to display the Industry Canada certification number of the module, preceded by the words “Contains transmitter module”, or the word “Contains”, or similar wording expressing the same meaning, as follows:

  • Contains transmitter module ISED: 20127-BRN404X

This End equipment should be installed and operated with a minimum distance of 20 centimeters between the radiator and your body. Cet équipement devrait être installé et actionné avec une distance minimum de 20 centimètres entre le radiateur et votre corps.

The end user manual shall include all required regulatory information/warning as shown in this manual.

Revision history

Revision Date Author Comments
010 2022-09-06 RK Split out from rest of the Boron line
011 2022-09-07 RK Add additional port and pin information
012 2022-09-16 RK Add minimum Device OS version, is 4.0.0
013 2022-12-13 RK Update block diagram and antenna information
014 2023-01-11 RK Updated certifications, added ISED, removed PTCRB
015 2023-01-17 RK Added FCC § 2.1033(b)(5) Block Diagram
016 2023-01-31 RK Add Device OS versions
017 2023-03-07 RK Update BLE antenna text
018 2023-03-29 RK Updated 3.3V regulator
019 2023-04-28 RK Add conformal coating and flux notes
020 2023-07-18 RK Added alternate antenna ANT-FLXU
021 2023-11-13 RK Add full pin details

Known errata

Contact

Web

https://www.particle.io

Community Forums

https://community.particle.io