SparkFun
MicroMod Main Board - Double
· MPN: DEV-20595
This Double Main Board is a carrier for SparkFun’s MicroMod ecosystem, letting one MicroMod Processor Board connect to up to two MicroMod Function Boards. Th...
This Double Main Board is a carrier for SparkFun’s MicroMod ecosystem, letting one MicroMod Processor Board connect to up to two MicroMod Function Boards. The M.2 MicroMod connectors make it straightforward to align the keyed edge connectors and secure the boards with screws.
USB-C is provided for power and programming, with reset and boot buttons on board and the processor pins broken out to a 2x5 SWD header. It also includes a 2A resettable fuse, a 3.3V/1A regulator, and a dedicated 3.3V/500mA regulator for Qwiic devices.
For portable projects, the board includes a 2-pin JST connector and an integrated MCP73831 single-cell LiPo charge circuit set to 500mA. You also get a microSD socket for data logging, two Qwiic connectors with built-in pull-up resistors, status LEDs, switches, and PTH jumpers for measurement and low-power testing.
Note: A MicroMod Processor Board and MicroMod Function Boards are not included and will need to be purchased separately. A MicroMod Main Board Guide V2 and hardware documentation are available from SparkFun.
Features:
- Interfaces a MicroMod Processor Board with up to two MicroMod Function Boards.
- M.2 MicroMod connectors for keyed, screw-secured board installation.
- USB-C connector for power and programming the Processor Board.
- Jumper available on the back of the board to isolate the USB C's shield pin.
- Two buttons for reset and boot.
- Processor Board pins are broken out as 2x5 SWD pins.
- PTH jumpers for bypassing the fuse and measuring current consumption on the 5V and 3.3V lines for low-power testing.
- Two switches to toggle between the general-purpose pins and each Function Board's voltage regulator.
- Third switch to switch between different SPI chip select pins on the second Function Board.
- Four status LEDs are available for power and charging.
- Status LEDs can be disabled through the jumpers.
- microSD card socket for data logging.
- microSD socket can be disabled through the I/O pins.
- Two Qwiic connectors with built-in pull-up resistors for Qwiic-enabled I2C devices.
- MicroMod modular interface ecosystem connects a microcontroller “processor board” to various “carrier board” peripherals.
- MicroMod standard is designed to easily swap out processors and function boards on the fly.
- Rotate silkscreen for the connectors and a majority of the labels.
- Add TVS diodes for ESD protection on the USB pins.
- Add SHLD jumper to isolate the USB Type C connector's shield pin.
- Add a 5V MEAS PTH jumper as a measurement for 5V.
- Remove the 500mA/100mA selector for the LiPo charge circuit. The board now charges at a default rate of 500mA only.
- Add a DIVIDER jumper to remove the resistor divider that is connected to processor's "BATT_VIN/3" pin for low power applications.
- Add a dedicated 3.3V/500mA voltage regulator for the Qwiic port.
- Add GPIO control of 3.3V voltage regulator (I2C_SCL1-Processor).
- Add a LED for the 3.3V Qwiic port with a QWIIC LED jumper to disable.
- Add a transistor to disable power to the microSD socket (can be controlled using I2C_SCL1-Processor).
- Add multiplexed primary UART pins to send serial data to Function Board(s).
- Add two 2.2kΩ I2C pull-ups to the primary I2C pins with jumpers (I2C) to disable.
- Replace male header pins and 2-pin shunt with SMD switches to adjust the Function Board Power enable pins.
- Add option to adjust Function Board One's secondary SPI CS pin (i.e. "CS1-processor" and "A1-processor") with a SMD switch.
Specifications:
- Input Voltage Range via USB C Connector: 5V
- Input Voltage Range via LiPo Battery Connector: ~3.7V to 4.2V
- Built-in Resettable PTC Fuse: Rated 5V/2A
- AP7361C 3.3V Voltage Regulator: Rated 1A
- AP7347DQ 3.3V Voltage Regulator: Rated 500mA
- Integrated MCP73831 Single Cell LiPo Charge Circuit: 500mA
- Ports - USB Type C Connector: 1x
- Ports - 2-Pin JST Connector: 1x
- M.2 Connectors - MicroMod Processor Board: 1x
- M.2 Connectors - MicroMod Function Boards: 2x
- Qwiic Enabled I2C: 2x
- MicroSD Card Socket: 1x
- SWD 2x5 Header: 1x
- Built-in MUX: for UART1
- Buttons - Reset: 1x
- Buttons - Boot: 1x
- Switches: 3x
- Switch - Function Board Zero Power Enable Pins: included
- Switch - Function Board One Power Enable Pins: included
- Switch - SPI1 Chip Select Alternative Pins: included
- LEDs - VIN: 1x
- LEDs - 3.3V: 1x
- LEDs - Qwiic 3.3V: 1x
- LEDs - CHG: 1x
- Plated Through Holes: RST
- Plated Through Holes: 5V (MEAS)
- Plated Through Holes: V_BATT
- Plated Through Holes: 3.3V (MEAS)
- Jumpers: USB SHLD
- Jumpers: 5V MEAS
- Jumpers: 3.3V MEAS
- Jumpers: PTC
- Jumpers: 3.3V EN
- Jumpers: VIN LED
- Jumpers: 3.3V LED
- Jumpers: Qwiic 3.3V LED
- Jumpers: I2C
- Jumpers: Battery Voltage Divider
- Board Dimensions: 4.90" x 2.90"
Ideal for MicroMod builds that need multiple function boards, Qwiic I2C expansion, data logging, LiPo power, and easy access to programming and debug connections.
Jargon buster
Plain-language definitions for the technical terms used above.
- AP7361C
- A specific 3.3 V voltage regulator chip used to provide a stable lower voltage from the board’s input power. The regulator’s current rating matters because it limits how much 3.3 V power is available for the module and connected parts.
- CS
- CS stands for chip select, a control pin used by SPI devices to tell which connected device should listen. It matters when you connect more than one SPI module to the same microcontroller, because each device usually needs its own CS pin.
- ESD protection
- ESD protection helps protect electronics from damage caused by static electricity discharges. It is useful on development boards because cables, sensors and modules are often plugged and unplugged during prototyping.
- GPIO
- General-purpose input/output pins are microcontroller pins you can set in software to read signals, switch devices on and off, or connect to peripherals. The number of GPIO pins matters because it limits how many buttons, LEDs, sensors, and other parts you can wire directly to the board.
- I2C
- I2C is a two-wire communication bus used by many sensors and small modules. It matters because several I2C devices can share the same two wires, but each device needs a compatible address and your controller must support I2C.
- LED
- A light-emitting diode is a small electronic component that lights up when current flows through it in the correct direction. In this kit, LEDs create the flashing effect, so polarity and correct soldering matter for the project to work.
- LiPo
- A lithium polymer rechargeable battery commonly used in portable electronics projects. It matters because LiPo batteries need correct charging circuitry and care, and this board includes hardware intended for that battery type.
- M.2
- A compact edge-connector format commonly used to plug small modules into a carrier board without soldering. On this product it is the physical connector used by the MicroMod system, so compatibility with the matching processor board is important.
- MCP73831
- A lithium battery charger chip used to safely charge a single-cell LiPo battery. It matters because it lets the board recharge a battery from USB or another input without needing a separate charger module.
- microcontroller
- A microcontroller is a small computer on a chip that runs your program and controls connected inputs and outputs. For this product, it is the part that reads buttons and sensors, drives the display and speaker, and communicates over Bluetooth.
- MicroMod
- A modular board system where a small processor board plugs into a separate carrier board that provides connectors, power, and peripherals. It matters because this carrier board needs a compatible MicroMod processor board before it can run your project code.
- microSD card
- A microSD card is a small removable memory card used to store files such as audio tracks. For this product, the card is where the sound files live, so its capacity and formatting can affect how many sounds you can use.
- PTC fuse
- A resettable fuse that increases its resistance when too much current flows, helping protect the board from short circuits or overloads. It matters because it can recover after a fault instead of needing replacement like a traditional fuse.
- PTH
- Plated through-hole means the pin holes are metal-lined so solder connects the pad on both sides of the board. It is useful for connectors and headers that need a strong mechanical and electrical connection.
- Qwiic
- Qwiic is a plug-in connector system for I2C devices that uses small 4-pin cables, so you can connect compatible sensors without soldering. It matters because your controller or adapter also needs Qwiic, or you will need a cable or breakout to wire it up.
- RST
- Short for reset, a control pin used to restart or initialise a device from a microcontroller. It matters because this sensor requires the RST pin to be connected for some communication setups.
- Shield
- An add-on board that plugs into a main controller board to give it extra features such as sensing, motor control or communication. Knowing a product supports shields helps you judge whether it can connect neatly into an existing maker-board setup.
- SPI
- A fast serial communication bus often used for displays, memory cards, and sensors. It matters because SPI devices need specific pins for clock and data, plus a separate chip-select line for each device.
- SWD
- Serial Wire Debug is a two-wire programming and debugging interface used with many microcontrollers. It matters if you need low-level access to program, recover or debug the processor board connected to this carrier.
- UART
- UART is a simple serial connection that sends data over separate transmit and receive wires, often labelled TX and RX. It matters because this module is designed to replace a wired UART cable with a wireless link while keeping the same serial data format.
- UPS
- An uninterruptible power supply is a battery-backed power system that keeps a device running when external power is unplugged or fails. For an embedded computer, it helps prevent sudden shutdowns that can corrupt files or interrupt a project.
- USB-C
- A modern reversible USB connector used for power and data connections. On this product it matters because it can connect directly to a computer as well as to a microcontroller project.
MicroMod Main Board Double Schematic
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Supplier page — sparkfun.com
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