We finally have everything in-house to start the second production run!
As mentioned in the last update, I ordered factory programmed Padauk PMS150C-U06 chips from Sino-Mos to provide a reliable reset for the PHY chip on every board. They finished programming them a little sooner than expected, and they arrived last week.
I expected everything to be OK with them, but you never know 100% for sure if everything was understood correctly when dealing with China, until you actually have something in-hand. For one thing, I was relieved that they had indeed re-reeled them. It would have been a big bummer if I would have received a bag of loose SOT-23’s. :)
Then I had to make sure they were indeed programmed. So I reworked another 12 boards from the first batch that didn’t initialize the PHY correctly with chips from one of these reels, and after rework they all work flawlessly!
Getting these chips has actually been a smoother experience than I had expected. It’s kind of cool to now have a low-cost custom chip that does exactly what I want it to do, with its own partnumber and everything. PMS150C-559 is now forever an "ESP32 Ethernet PHY reset manager". Maybe I should write a datasheet for it. :)
Also, since I have 9,000 of them, I can definitely spare some if anyone is making their own ESP32 board with Ethernet and wants a canned solution to deal with the LAN8720A PHY reset. There’s an updated schematic that shows how the chip is used on the new wESP32 revision on Hackaday.io. So get in touch if you want to buy some.
I took a little risk and ordered new PCB panels that use the PMS150C-559 before I had verified the factory programmed chips. But it had all been taking much longer than expected already and some backers have been wondering when they’d receive their reward, so I tried to recoup some time that way. The new PCBs and stencil arrived today!
So now I have everything in-house to get this build started. I’m actually going to pack up a kit and have 500 of them built at a CM in Mexico. I’m branching out to try different contract manufacturers to hopefully speed things up on the production side. Colorado Tech Shop did OK with the smaller batches, but as my volume increases, the only way I can keep up with demand is to have various CMs qualified to run these boards. The other 500 can be built by Colorado Tech Shop if they have the time or another CM I might qualify. Doing this costs more than having a single 1,000 unit run at one place, but it spreads the risk a bit if some of them don’t work out, and it increases the number of suppliers I can work with.