Did you check diode mode to ground at 3V8_AON?
Don't waste time with o-scope; as no output voltage, no pulse for sure!
Don't waste time with o-scope; as no output voltage, no pulse for sure!
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820-2655-A no PP3V8_AON
- Thread starter Roan
- Start date
Not at all; you have short to ground!
Alright! I'll inject voltage tomorrow. Since it's 4.5 ohms I expect it to be more downstream. What max amps should I consider on this line? Voltage preferably not near 3.8V I assume?
I tried injecting a bit earlier when I already thought of it as a short and the resistance jumped down to 0.08 ohms as calculated from the PSUs voltage and amperage.
I tried injecting a bit earlier when I already thought of it as a short and the resistance jumped down to 0.08 ohms as calculated from the PSUs voltage and amperage.
4.2V shouldn't be a problem.
Anyway start with just 1V and slowly increase it.
A good thermal camera should detect the culprit before 3V.
BTW, set amp limit to max on PSU first.
Anyway start with just 1V and slowly increase it.
A good thermal camera should detect the culprit before 3V.
BTW, set amp limit to max on PSU first.
Gottem! Set the PSU to 1V and max 5A, after turning it on voltage dropped down to 0.4V and one cap lit up: C7702. Only thing now is that I dont have a donor board and also not a new pack of caps with known capacitance etc. What properties of the cap are important? Or is leaving it off a smart option?
That is 10uF capacity at 6.3V nominal voltage; 0402 is the package size (dimensions).
And you can find it on older boards.
There are many capacitors placed, so shouldn't be a problem to use the machine without one.
Never buy new ceramic capacitors; just use scrap boards, following schematic and boardview.
And you can find it on older boards.
There are many capacitors placed, so shouldn't be a problem to use the machine without one.
Never buy new ceramic capacitors; just use scrap boards, following schematic and boardview.