The Zipit Z2 breakout boards arrived today and I promply pieced one together for testing. I’ve encountered a few problems already so another revision will be in the works. The one board I partially assembled today is working with a few modifications.
First, I had to mill out the through holes for the Hirose connectors. The PCB fabricator doesn’t support oval shaped through holes so I had them drill two holes on either side of the pad. My plan was to mill between them which I did, but it turned out to be a tedious task. The next revision will use a single round though hole for the 4 tabs on the Hirose connector.
The second problem is that I connected the TPS61240 regulator to the DC_IN pin. For some reason I was thinking that it had 3.3V when not connected to AC power but it doesn’t. Whoops. I got the board working by cutting traces, rerouting DC_IN and connecting the regulator to 3.3V which can be seen in the photos.
The last problem I’ve encountered so far is that the Zipit will not charge from the USB OTG port. The Zipit recognizes that it’s plugged in and shows the charging icon in gmenu2x but it’s barely drawing any current. My bench power supply with current and voltage readout shows it’s drawing 0.09 amps. I also have an inline USB voltage/current display that shows only 0.03 amps being drawn. Perhaps the traces are too small to supply more current? Please comment if you have any recommendations about this. In the mean time I cut the trace to USB_IN and connected the Micro USB port to DC_IN. This seems to work just fine.
Parts for the relay header are on the way and should be here by Monday. I assume the GPIO header works but I will test a few just to be sure. The audio connections need to be tested as well. So far I’m pretty happy with it. The problems will be easy to fix.
Update: Tested a few GPIOs and they work fine. Audio out header works. I was worried about interference but sound was crisp and clear. I tried a condenser mic but couldn’t get it to work. Not sure if its the mic, my alsa settings or the breakout board.