M.2 breakout board

The M.2 breakout board is a convenient way to prototype with the B-SoM and M-SoM modules.

Block diagram

Board features

Setup

Install the SoM

The M.2 SoM breakout board requires a Particle M-SoM or B-SoM module. Install it in the M.2 socket (21) and secure it with a thumbscrew.

Connect antennas

The M.2 breakout board can be used with the standard flexible Particle antennas or the SMA adapters included on the breakout board.

• Plug the cellular antenna into the U.FL connector labeled CELL on the SoM. Remember never to power up this board without the antenna being connected. There is potential to damage the transmitter of the u-blox module if no antenna is connected.
• If you are planning to use BLE, connect the 2.4 GHz antenna (the smaller one) to the BT U.FL connector on the SoM.
• The flexible Particle cellular and BLE antennas should be included in the M.2 SoM package, not the breakout board package.
• SMA antennas are not included with the M.2 breakout board. If used in a product, additional certification would be required to use a SMA antenna.

Install a power module

The M.2 breakout board includes two power modules; select and install the module you wish to use and install it in the power module socket (22).

Note the position of the notch to make sure the power module is installed in the correct orientation and make sure all of the pins are aligned with the socket on the breakout board.

PM-BAT power module

The PM-BAT power module allows the Particle SoM to be powered by a LiPo battery or DC adapter.

• Install the PM-BAT module in the power module socket (22).
• Connect the LiPo battery (2).
• Optionally connect the AC power adapter to VIN (7). With PM-BAT, VIN must be 5 - 12 VDC.
• You must use the LiPo battery, AC power adapter, or both, when using PM-BAT. You cannot power by USB only.
• The LiPo battery can be only be charged by VIN, it cannot be charged from USB.

PM-DC power module

The PM-DC power module allows the Particle SoM to be powered by an AC power adapter or external DC power source.

• Install the PM-DC module in the power module socket (22).
• Connect the power adapter to VIN (7). When powering PM-DC by VIN (barrel connector), 5 - 12 VDC is required at 12 watts.
• Power on the VIN barrel connector is required when using PM-DC; you cannot power the breakout board only by USB power.

Power on device

Turn on the appropriate power switches (4, 6).

The RGB status LED should turn on. Typically it will blink white once, then blink green though it may display a different pattern.

Device setup and claiming

Connect the USB connector (3) to your computer. This is needed only for setup.

Visit https://setup.particle.io/ to finish setting up your device.

Onboard peripherals

Qwiic (8)

The SparkFun Qwiic system provides an easy way to expand and test various sensors, input devices, and displays. Multiple peripherals can be daisy-chained to a single port. The Adafruit Stemma QT are compatible with Qwiic and can be mixed and matched as well.

For more information, see Qwiic.

Grove connector (9)

Additionally, Grove system of sensors and peripherals from Seeed Systems is another easy way to add peripheral devices. The M.2 breakout board has one Grove connectors connected to pins A1 and A2 that can be used as GPIO or analog inputs. This port cannot be used with I2C or Serial Grove peripherals.

Feather connector (21)

The Feather connector can be used for Adafruit FeatherWings, such as displays, sensors, and Ethernet. You cannot plug a Feather MCU into this socket!

Feather pin mapping - M-SoM

Feather pin mapping - B-SoM

Jumpers (22)

These jumpers connect the Feather A pin side to the M.2 connector. They can also be used to remap pins by using jumper wires instead of solid jumpers.

Jumpers (23)

These jumpers connect the Feather D pin side to the M.2 connector. They can also be used to remap pins by using jumper wires instead of solid jumpers.

LiPo connector

Note that the M.2 breakout board includes a 3-pin JST-PH connector (left), not the 2-pin JST-PH connector on some other Particle devices (right). The TS pin is expected to be connected to a 10K NTC thermistor in the battery pack. The TS jumper (26) must be installed for normal operation with a temperature sensor.

Looking at the exposed end of the connector attached to the battery

If you wish to use a battery without a temperature sensor, remove the TS jumper (26) and use a 3-pin to 2-pin JST-PH adapter, or change the shell of your JST-PH 2-pin connector to a 3-pin shell. The pin can be swapped without cutting, soldering, or crimping. See the battery guide for more information.

If purchasing a LiPo battery from a 3rd-party supplier, beware as the polarity of the JST-PH connector is not standardized and may be reversed. Permanent damage to the breakout board can occur if powered by reverse polarity on the JST connector. See the battery guide for additional information.

The included battery is a 3100 mAh 3.7V LiPo battery with temperature sensor. Battery datasheet.

3V3_AUX power

Both the PM-BAT and PM-DC power modules support an auxiliary 3.3V power supply. This is used to power the Feather socket 3V3 and the 3V3_AUX rail.

3V3_AUX is powered from 3V3 via a load switch (TPS22918). It can supply up to the full 2A of 3V3. It defaults to off due to a pull-down resistor on EN_AUX. EN_AUX is connected to pin D23; set this pin to output high to enable 3V3_AUX.

// Enable 3V3_AUX
pinMode(D23, OUTPUT);
digitalWrite(D23, HIGH);

Devices using the Particle Power Module include a 3V3_AUX power output that can be controlled by a GPIO. On the M.2 SoM breakout board, this powers the Feather connector. On the Muon, it powers the Ethernet port, LoRaWAN module, 40-pin expansion HAT connector, and QWIIC connector.

The main reason for this is that until the PMIC is configured, the input current with no battery connected is limited to 100 mA. This is insufficient for the M-SoM to boot when using a peripheral that requires a lot of current, like the WIZnet W5500 Ethernet module. The system power manager prevents turning on 3V3_AUX until after the PMIC is configured and the PMIC has negotiated a higher current from the USB host (if powered by USB).

This setting is persistent and only needs to be set once. In fact, the PMIC initialization normally occurs before user firmware is run. This is also necessary because if you are using Ethernet and enter safe mode (breathing magenta), it's necessary to enable 3V3_AUX so if you are using Ethernet, you can still get OTA updates while in safe mode.

After changing the auxiliary power configuration you must reset the device.

PM-BAT interface

The M.2 breakout board can be used with the PM-BAT power module that includes the bq24195 PMIC and MAX17043 fuel gauge chips which interface by the pins below

Using ethernet

The M.2 breakout board does not contain Ethernet like the previous B-Series Eval board. You can, however, add it using the Adafruit Ethernet FeatherWing in the Feather socket.

Be sure to connect the nRESET and nINTERRUPT pins (on the small header on the short side) to pins D3 and D4 with jumper wires. These are required for proper operation.

The default mapping for the B-SoM and the original B-SoM eval board is listed below, but you may want to use Ethernet pin remapping to reassign the pins.

Firmware example

The following code can be used to enable Ethernet on the M.2 SoM breakout board. This only needs to be done once and the device must be reset after configuration for the changes to take effect. It requires Device OS 5.9.0 or later.

// Enable 3V3_AUX
SystemPowerConfiguration powerConfig = System.getPowerConfiguration();
powerConfig.auxiliaryPowerControlPin(D23).interruptPin(A6);
System.setPowerConfiguration(powerConfig);

// Enable Ethernet
if_wiznet_pin_remap remap = {};
remap.base.type = IF_WIZNET_DRIVER_SPECIFIC_PIN_REMAP;

System.enableFeature(FEATURE_ETHERNET_DETECTION);
remap.cs_pin = D5;
remap.reset_pin = PIN_INVALID;
remap.int_pin = PIN_INVALID;
auto ret = if_request(nullptr, IF_REQ_DRIVER_SPECIFIC, &remap, sizeof(remap), nullptr);

Using SD card

The M.2 breakout board does not contain a Micro SD card socket as the previous B-Series Eval board did. You can, however, add it using the Adafruit Feather connector.

The Adalogger FeatherWing - RTC + SD Add-on For All Feather Boards contains a Micro SD card socket.

It is also possible to cut the a trace jumper for SDCS and use a different pin for SDCS. Note that this will use SPI (primary SPI) but the B-Series Eval board use SPI1 so your SD card initialization code will be different.

See the Adafruit tutorial for additional information.

Expansion header

Expansion header - M-SoM

Expansion header - B-SoM

Full pin listing

Skip past this section (the full pin listing is long)

Module Pin 1 (GND)

Module Pin 2 (VCC)

Module Pin 3 (GND)

Module Pin 4 (VCC)

Module Pin 5 (GND)

Module Pin 6 (VCC)

Module Pin 7 (GND)

Module Pin 8 (3V3)

Module Pin 9 (GND)

Module Pin 10 (SOM10)

Module Pin 11 (SOM6 / D21)

Module Pin 12 (SOM11 / GNSS_TX)

Module Pin 13 (SOM7 / D20)

Module Pin 14 (D1)

Module Pin 15 (A0)

Module Pin 16 (D0)

Module Pin 17 (A1)

Module Pin 18 (MODE)

Module Pin 19 (A2)

Module Pin 20 (RST)

Module Pin 21 (A3)

Module Pin 22 (TX)

Module Pin 23 (GND)

Module Pin 24 (RX)

Module Pin 25 (A4)

Module Pin 26 (D3)

Module Pin 27 (A5)

Module Pin 28 (D2)

Module Pin 29 (A6)

Module Pin 30 (SOM0 / CELL USBD+)

Module Pin 31 (A7)

Module Pin 32 (SOM1 / CELL USBD-)

Module Pin 33 (GND)

Module Pin 34 (D8)

Module Pin 35 (SOM14)

Module Pin 36 (MISO)

Module Pin 37 (SOM15 / A5)

Module Pin 38 (MOSI)

Module Pin 39 (SOM16 / D27)

Module Pin 40 (SCK)

Module Pin 41 (SOM17)

Module Pin 42 (GND)

Module Pin 43 (SOM18 / D26)

Module Pin 44 (SOM12 / D24)

Module Pin 45 (RGBR)

Module Pin 46 (SOM13 / D25)

Module Pin 47 (RGBG)

Module Pin 48 (D22)

Module Pin 49 (RGBB)

Module Pin 50 (D23)

Module Pin 51 (SOM5)

Module Pin 52 (D4)

Module Pin 53 (SOM6)

Module Pin 54 (D5)

Module Pin 55 (SOM7 / SOM8)

Module Pin 56 (D6)

Module Pin 57 (SOM8 / SIM_DATA)

Module Pin 58 (D7)

Module Pin 59 (GND)

Module Pin 60 (SOM9 / SOM8)

Schematics

To be provided at a later date.

Mechanical specifications

Dimensions and weight

To be provided at a later date.

Revision history