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jkominek / piano-conversion

Hardware, and some firmware, for acoustic piano to MIDI controller conversion.
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Check BOM against JLCPCB SMT parts list. #21

Open jkominek opened 3 years ago

jkominek commented 3 years ago

JLCPCB being one of the easier (and still reasonably priced) ways for the average person to get a board assembled, I'm trying to keep the parts used to things that are available via JLCPCB.

In the unlikely event anyone else tries to work on this, you'll probably need to ask me some questions about part choice/suitability. Some are left underspecified in the schematic, some might be too specific. I can either describe the relevant attributes for a given part ("needs long term stability and low input offset"), or review a few choices presented to me.

jkominek commented 3 years ago

I went looking through JLCPCB's basic parts library for FETs for the main board. Looks like the relevant options are all SOT-23-3, so I'll need to tweak that for rev 1.

After brief inspection, the suggested parts are: N-channel: 2N7002 (C8545), P-channel: AO3401A (C15127)

davidedelvento commented 2 years ago

Hi @jkominek have you made any progress on this? And also with the CPL files? I would like to start ordering some boards, but I see only gerber files in https://github.com/jkominek/piano-conversion/releases so I'm not sure how to ask jlcpcb to do the SMT assembly without them.

jkominek commented 2 years ago

No progress on this. I'm not sure it would even be useful at this point, with the widespread parts shortages. I was expecting to have to change some parts in order to make the board JLCPCB-assemble-able, which is fine, but doing it right now seems like an exercise in frustration.

jkominek commented 2 years ago

I have started looking things up, in hopes of replacing some parts with ones which are more available / have more drop-in replacements, and also just assessing the situation. I used fewer distinct parts than I remembered!

https://github.com/jkominek/piano-conversion/wiki/Parts-Compatibility

So far it looks like the only totally unavailable parts are the microcontrollers, and the USB ESD protector. If there isn't anything else broadly available with a matching footprint, I'll talk to a real EE and design in something more generic.

davidedelvento commented 1 year ago

Compile total BOM. The first pass of this should probably ignore resistor values, the ones in the schematics are very hand-wavy and don't strictly match what I've used.

Is this still the case? I see most resistor values are populated in the ADC board and they seem okay to me. Instead there are a number of missing capacitor values (some of which in the PCB appear to be connected nowhere, which probably should be a separate issues?)