https://i.imgur.com/DoOscag.jpg

https://i.imgur.com/MLWtyfX.jpg

Original Post with troubleshooting

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Hi all,

I'm getting towards the tail end of my gamma 3 build, but have hit some discrepancies with the basic sanity checks.

I'm getting non-0 values for the following measurements

LVDD (backplane) and G (backplane) ~6.5K

GVDD (backplane) and IG (backplane) ~15K

AVDD (backplane) and IG (backplane) ~10K

AVSS (backplane) and IG (backplane) ~10K

Additionally, when measuring the resistance takes a while to actually hit those numbers, ~30 seconds or so

Other points are also getting non-0 readings, but im assuming the above is the main problem I need to sort out first given the same results for each α24 channel.

IN+ (α24 L) and G (α24 L) ~250K

IN- (α24 L) and G (α24 L) ~250K

OUT+ (α24 L) and G (α24 L) ~18K

OUT- (α24 L) and G (α24 L) ~8K

OUT (α24 L) and G (α24 L) ~25k

IN+ (α24 R) and G (α24 R) ~250K

IN- (α24 R) and G (α24 R) ~250K

OUT+ (α24 R) and G (α24 R) ~18K

OUT- (α24 R) and G (α24 R) ~8K

OUT (α24 R) and G (α24 R) ~25K

What i've tried so far:

- Unplugging all wiring harnesses - same results
- removing all modules - same results
- Reflowing all of the galvanic isolation chips on top - same results
- Reflowing all solder joints underneath the board - same results
- Visually inspecting for shorts - couldnt see any

https://i.imgur.com/awi7Xpf.jpg

https://i.imgur.com/HKcYdR4.jpg

I'm not sure how to start running this down - any help would be much appreciated