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Ok, my problem is that they seem glitchy, a jumping tensions (always under 200mV). Can the be caused by U8100 on 1V8_S2 even though it is generated by U7700? Or is this a sign of a faulty U7700?
So I think I found a replacement for my U8100. I thought don’t understand if/how the absence of 1V8_S2 and 1V2_S2 could be caused by a faulty U8100 and if not so what could be the problem. Also as you pointed out U8100 has some platform-dependent pins, what exactly does that mean? I found a...
All LDOs out works (both U8100 and U7700) except for 3V3_AON, could not measure the coils, I can't reach the contacts porperly, I'll get nwe probes. Any idea on how to get a new U8100?
So I did some more test, and checked every single LDO out from PP3V8_AON_MPMU_ISNS in U8100 from multiple places and looks like PP1V8_AON and PP1V2_AON works, but can't get PP3V3_S2. Is this due to a bad U8100 or could it be something else?
Could it be that the short was caused by me measuring the resistance when I shouldn’t? If I find a 8100 can they be swapped or are they “bounded” to the Soc? It’s weird that it is damaged, no liquid came in contact with it, is there something else I could test to be sure?
Ok so measuring 1V2_S2 from C8086 (next to L8280) I get a short to ground with a jumping value of resistance only when the power is plugged. Regarding the LDOs output of 3V8_AON on U8100, I tested PP3V3_S2 via CF231 and get no voltage but neither a short to ground
So I must have done something wrong before, now it is not shorted out (maybe before I tried with power on, but that shouldn’t change anything right?). Anyway now there is no short, and the readings I gave you were diode mode. Not really sure how to proceed
I measured 1V8_s2 and 1V2s2 from the connected caps next to them (could not get the probes to the inductors themselves) and it looks like they are shorted out, GND is connected to both 1V8_s2 and 1V2s2. Regarding output from PP3V3_S2 LDOs in U8100 I tested them by looking at resistors that...
Thnaks for the explanation, I just checked and the 3V8 line is present, but others (1V8 and 1V2) are not, knowing that where should I look for shorts? Should I look for where 1V2 and 1V8 is generated, if so is there a specif place in the motherboard for that or maybe components I should look for?
Not sure what you are referring to with pages 36, 41. Anyway I measured both U7700 and U8100 but it looks like there is no voltage. I noticed that when measuring U7700 using a cap (C80F2, see image) a little smoke comes out and the tester probes ""sticks"" to it, not sure how to diagnose that...