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Fix Motor Drivers Bulk Capacitor Values (Rev.12 Branch) #29

Closed FL140 closed 1 year ago

FL140 commented 1 year ago

Version Number

mobo Rev.12 Branch 20.05.2023 ~01:00 UTC

Bugfix or Enhancement

Bugfix

Description

It looks like placeholders (100nF) have been used for the motor driver bulk capacitors.

Suggested Solution

Replace the capacitors C18 & C20 with a reasonable size. Probably something in the range of 22uF.

sphawes commented 1 year ago

Hi @FL140! Thanks for the note! These values are not placeholders, they're following the recommended values from the DRV8837 datasheet:

Screenshot 2023-05-24 at 4 55 32 PM

I don't think they're intended to act as bulk capacitors. We have a 470uF cap on the 10v rail that provides bulk capacitance for the VM pin on the drivers.

Screenshot 2023-05-24 at 4 59 07 PM

Also, in an effort to not have duplicate issues, I'm going to close this issue and we can use this issue to sort out cap values.