Christian Hirsch Taps Nordic's nRF9151 to Bring Broad Connectivity to the MicroMod Ecosystem

Electronic and embedded engineer Christian Hirsch is preparing to launch a MicroMod Processor based around the Nordic Semiconductor nRF9151 — providing LTE-M cellular, NB-IoT, DECT-NR+, and Global Navigation Satellite System (GNSS) connectivity in a single compact module.

"[The] nRF9151 MicroMod Processor is based on the nRF9151 System in Package from Nordic Semiconductor," Hirsch explains of his creation. "It has an M.2 E-key connector and is compatible with SparkFun's MicroMod ecosystem. This 22×22mm board brings LTE-M, NB-IoT, NB-NTN and DECT-NR+ communication, as well as GNSS functionality, to the MicroMod ecosystem. It has external flash memory to offer remote firmware upgrades and an additional GPIO [General-Purpose Input/Output] expander to access almost all of the MicroMod pins."

Embedded and hobbyist electronics specialist SparkFun launched the MicroMod range around six years ago as a way to combat waste and duplicated effort in the face of the unstoppable march of technological progress. Reusing connectors originally designed for M.2 devices, the company broke out the microcontrollers and microprocessors that would normally be installed on development boards into modules — meaning that it's possible to switch processors by simply swapping out a module, without having to buy a whole new development board and potentially restart a project from scratch.

The MicroMod standard is open, meaning anyone — not just SparkFun — can design their own modules and carriers. That's exactly what Hirsch has done: taken the Nordic nRF9151 and put it into MicroMod Processor format. The wireless microcontroller chip provides an Arm Cortex-M33 processor core along with a modem and radio-frequency frontend delivering a range of connectivity options, from LTE-M cellular through to narrowband non-terrestrial network (NB-NTN) satellite communication capabilities. There's 8MB of flash storage with support for over-the-air updates, plus 256kB of static RAM (SRAM).

While the processor module should slot into any MicroMod carrier board, Hirsch has also designed an Arduino UNO-style carrier option featuring an STMicroelectronics STM32 microcontroller, Serial Wire Debug (SWD) support, a USB-UART bridge accessible alongside the debug over a single USB port via a built-in hub, a Qwiic header plus GPIO pins, and a user-programmable RGB LED.

Interested parties can sign up to be notified when Hirsch's crowdfunding campaign goes live on Crowd Supply; the engineer has pledged to make schematics, board definitions, and code samples for the Zephyr real-time operating system (RTOS) available before the campaign's close, under an as-yet unspecified open source license.