About Sequent Microsystems

Bridging Raspberry Pi to the Real World

The Raspberry Pi is a compact yet powerful platform, ideal for IoT, home, and industrial automation projects. However, it lacks native I/O capabilities to directly interact with sensors and devices. At Sequent Microsystems, we fill that gap with reliable, feature-rich I/O expansion HATs for Raspberry Pi.

Our Product Capabilities

We design and manufacture cards that extend the Pi’s functionality with:

  • Analog inputs/outputs: 0–3.3 V, 0–10 V, 4–20 mA

  • Optically isolated inputs: 3–240 V AC/DC

  • Relays and solid-state outputs (2–16 channels)

  • Event counters and quadrature encoders

  • Thermistor, thermocouple, and RTD sensor support

  • RTC with battery backup

  • Communication: RS485/MODBUS, RS232, RS422, CAN, M-BUS, 1-Wire

  • MOSFET and TRIAC load drivers

Stackable & Flexible Designs

All HATs communicate with Raspberry Pi through the I²C interface, leaving GPIO pins free. Most are stackable up to eight layers, enabling flexible configurations. Our “Swiss Army Knife” HATs for Home, Building, and Industrial Automation integrate multiple features into a single board for maximum versatility.

Built for Reliability

We engineer every board for demanding environments. Key features include:

  • Hardware watchdogs to reset the Pi if unresponsive

  • Pluggable terminal blocks for robust connections (16–28 AWG, 8 A/300 V)

  • Brass spacers for secure stacking

  • Wide power support: 12–24 V input, up to 5 A output to the Pi

Complete Ecosystem

Our product line also includes:

  • Super-Watchdog with battery backup, for power-loss resilience

  • Stackable Smart Fan for efficient cooling

  • DIN-rail kits and breakout boards for wiring flexibility

Open Source Commitment

Every Sequent Microsystems board is open source. We provide schematics, command-line tools, Python libraries, and support for Node-RED, OpenPLC, Arduino, and more via GitHub.

Custom Development

Many of our solutions originated as customer requests. We welcome custom controller projects—with or without Raspberry Pi—delivering high-quality, affordable hardware for OEMs and automation professionals. 

Contact us today to explore how Sequent Microsystems can power your next automation or IoT project.