Microcontroller Boards


A certified ESP32-S3 module with LTE-M, NB-IoT, and GNSS for prototyping and production

This project is launching soon.

Coming Soon
You'll be notified about news and stock updates for this project.

Walter is a small form-factor IoT system-on-module which combines the powerful ESP32-S3 processor with a 5G modem and GNSS receiver. On top of the ESP32-S3’s many built-in peripherals, such as UART, SPI, I2C, CAN, Wi-Fi b/g/n, and Bluetooth 5, Walter also boasts the second-generation Sequans GM02SP LTE-M/NB-IoT 5G modem and GNSS receiver.

The Walter module can be used for both prototyping and production, as it will be certified for FCC, CE, Australia SDoC, and New Zealand SDoC. We also guarantee a minimum of ten years availability, which makes it a uniquely reliable building block for your IoT application.

Walter comes with a range of 100% open source software libraries for jump-starting your 5G IoT project in minutes. So you can program in familiar languages and toolchains, Walter supports ESP-IDF, Arduino, Micropython, and Toit. No special dongles are needed to program Walter - just connect it directly to your development machine via a normal USB Type-C cable.


Walter has a built-in Wi-Fi and Bluetooth antenna, and relies on external antennas for optimal LTE-M/NB-IoT and GNSS operation. There are two u.FL connectors especially for this purpose. We have chosen Taoglas as the recommended antenna partner because of their quality and ten-year availability guarantee. The antennas are designed to be stuck onto a product case. This self-adhesive flexible design makes it possible to easily integrate the antennas into your projects.

Carrier Board

Although it is possible to use Walter completely standalone, the system-on-module is designed to be incorporated into a product by plugging it into some kind of carrier board. We have designed a carrier board for Walter which allows you to build proof-of-concept IoT products in seconds. The name of this carrier board is Walter Feels. It contains everything you need to build a battery-powered IoT sensing platform:

Use Cases

Walter has been created for remote sensing and control applications. In the past few months we have been working hard on perfecting our module by incorporating feedback from many beta testers, who have given us insights on possible use cases for Walter:

The above examples are only the tip of the iceberg, your creativity is the only limiting factor! Our team is already thinking about pet trackers, online delivery ticket printers, IoT access control systems, remote pump controls, and more.

Features & Specifications

Pinout Diagram

Open Source

We are continuously improving the documentation of Walter and its accessories. We also actively encourage everyone to contribute to this effort. Currently the following resources are available:

First Production Run

Walter is ready for production and conformity testing. In the past few months we have been working closely with the production house to get the design for manufacturing (DFM) just right. Below is a video showing the complete manufacturing process.

In the Press

Hackster News

"This board targets the IoT market. So, it takes power consumption seriously."

Circuit Digest

"A cutting-edge, certified ESP32-S3 module with LTE-M, NB-IoT, and GNSS capabilities, set to revolutionize IoT (Internet of Things) prototyping and production."


"Walter is an ESP32-S3-based IoT system-on-module supporting LTE-M/NB-IoT 5G and GNSS. This compact device is certified for FCC, CE, Australia SDoC, and New Zealand SDoC, so this module can be used for prototyping and production."

About the Team


Knokke-Heist, Belgium  ·  dptechnics  ·  dptechnics  ·  dptechnics.com

We develop and produce next-generation, internet-connected products, from embedded systems to software to industrial design.

Ronny Pape


Dries Vandenbussche


See Also

Subscribe to the Crowd Supply newsletter, highlighting the latest creators and projects