Grayscale 7x11 Matrix

A project log for D1 Mini Matrix Deluxe Shields

Shields for the D1 Mini ESP8266 board using the ISSI chips

Radomir Dopieralski 5 days ago1 Comment

The third chip that I got from ISSI is IS31FL3736. It's very similar to the IS31FL3733, except it only drives up to 8×12 LEDs. That's perfect for those 7×11 LED matrices that I got!

I actually designed that shield a while ago, and assembled it when it came. But it didn't work, at least not reliably -- the chip would sometimes be visible on the I²C bus, and sometimes not, and sometimes it would start behaving weird after some time... I put it all to my poor soldering skills and the really tiny QFN package, and gave up on it for a while.

Yesterday, after debugging some problems with the IS31FL3733 on the #PewPew FeatherWing, which were solved by adding a decoupling capacitor across the power, I decided to dig out the old board and try adding a decoupling capacitor to it too. And what do you know, it works perfectly fine after all!

The PCB is here:

And the updated MicroPython library for driving it:


davedarko wrote 5 days ago point

woot :)

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