v7 PCB testing and QC in our small office

[martinberlin]

In this short post we wanted to show, me and my father from Fasani Corp, what is our Quality Compliance tests that we do before preparing PCBs. In this latest batch of 20 my father soldered already 14 and I started to test them today. I though that this could be an interesting starting point for those who also want to send a batch to production. For those who not, we have from time to time epdiy v7 on Tindie, that we sell to developers that do not want or do not have the time to learn how to send PCBs to JLCPCB (Or any other provider)

We solder the MCU ESP32S3 and sometimes also another simple ICs by hand but most of the rest is professionally assembled.

v7 QC testing: 4 PCBs in this batch put away: 3 have UART issues, 1 has I2C communication issues, need to be revised with Microcospe and resoldered. at least 20% of each batch have something since we are not perfect soldering the MCU.

First test: All data pins and signals (except slow signals)

PCB tester is open-source in https://vroland.github.io/epdiy-hardware/
VIDEO demo: https://x.com/martinfasani/status/1784479591395979300

Second test: With 9.7" 1200x825 display

With first test we know that the IO data pins are good soldered since the 16 green LEDs should shine one at a time. And we know also that the fast signals that are connected directly to an IO are also working.
TODO: Add also a slow signals test (Those that are dealt with the IO expander PCA9**)
But we still don't know if the high voltages work (FET gates: -20 & +22, plus pixel driving volts: +15 -15) so we can only finalize this 2nd test and say our PCB works after this.
Seeing the Dragon or the Demo working and flashing the Eink display.