This is a page to keep track of our PCB revisions, document design changes, and receive feedback.
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- Remove extra regulator circuit (Kevin's), source smaller crystals, make all resistors and LEDs 0603
- Fix trace lengths for crystals
- Reverse voltage protection? Decided not to implement on controller as the 12V connector will be on carrier board
- Fix all footprints to match the Hardware Style Guide - Still in progress
- Replace board info silkscreen as directed in the Hardware Style Guide - Incomplete, will do for next rev
- Connector changes:
- Combine SWD and UART headers (we may be able to hack the programmers to also be UART to USB adapters) or replace them with prototyping headers - Used 6 pin SMT 0.1" header
- Replace 12V connector with test points - Decided not to use test points as the regulator has already been tested (decoupling caps can be used as test points)
- Replace mezzanine connector with 0.8mm pitch equivalent to increase lifespan and verify mating height - 0.5mm pitch connectors need to be tested first, then consider this if necessary
- Change all connector part numbers to vertical connectors
- put male side of mezzanine on controller board
- Add guide holes for mezzanine footprint
- Signal connectors switched to Duraclik
- Silkscreen pinout for connectors
- Reduce induced ripple on 12V rail - Test with different input caps
- Improve ripple behavior on 3.3V rail - Will test with different output caps
- Calibrate regulator to 3.3V (currently at 3.36V) - Shouldn't be a big issue
- Get stencils
- Lower blue LED brightness (spec an LED ), raise green LED brightness
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- Regulator + diode works well, VCC is around 3.18V
- The resistor array was a little difficult to solder by hand, but overall the board didn't take too long even without hot air
- Need to check ripple on 12V, VCC, and VDDA.
Revision 6
Design Changes
- HSE is connected to the wrong pins (turns out it's been that way since before rev4)