esp32MX-E is an affordable, high-quality ESP32 board that puts all of the connectivity and power options you need into one carefully-designed, integration-friendly package that will save you time.

Prototype Runs

So far, we have tested two batches of prototype esp32MX-E boards. The first batch worked fine, but we made some small adjustments. The second batch seems to work 100%, but we’re not going to let that stop us from doing more tests.

Testing So Far

We have been validating our prototypes with the official ESP-IDF (v4) firmware. We tested our Ethernet port with the included iPerf sample program and our SD Card reader with the Espressif sample program.

We performed stress tests on the 3.3 V and 5 V switch mode regulators, running them at a couple of amps for many hours. They both performed exceptionally well, heating up only slightly and exhibiting a very low ripple voltage. This is due to the extremely low-resistance 3.8 A shielded inductors and our use of multiple capacitors in both the input and the output stages of our switch mode power supply circuit. Switching power between the USB C connector, the 2.1 mm barrel connector, and the external power input is seamless.

Documentation

We have also done many tests on the secondary STM32F030F4 microcontroller, which we use primarily for the Ethernet MAC reset circuitry, but which also provides additional I/O for user applications. As you can see from the documentation in our GitHub repository, esp32MX-E’s secondary microcontroller can be programmed in many different ways. We will soon be uploading the firmware for this CPU, which you can modify with the free STM32CubeIDE editor and STM32CubeProgrammer.

Our repository also includes some prototype PCB files that will help you create your own custom baseboards and daughterboards.