Atomrepair
Member
Board came in clean looking, no corrosion spotted anywhere so far. It drew about 2,5 amps at ~4 volts and didnt switch to 20V.
PPBUS_G3H and PP20V_USBC_XB_VBUS_F were shorted to GND
Q3100 had an internal short, bridging PPDCIN and PP20VB. replaced it.
Q3200 replaced just in case. pads for both of these looked bad. Pitted, dull grey. Probably from heating up a lot?
U3100 replaced from identical donor board - no damage found underneath, but did find some weird glue-looking stuff. reflowed U3200.
Short is gone, machine now sits at 5.18V with 20 mAmp.
I'm not (ever) completely sure if my U3100 replacement was a sucess. I have no stencil yet and am not looking forward to putting solder balls one by one on one of these again to rule it out. Is there anything else I can check to verify if U3100/U3200 are working properly? Anything else to measure with these symptoms?
U3100:
PPBUS_G3H and PP20V_USBC_XB_VBUS_F were shorted to GND
Q3100 had an internal short, bridging PPDCIN and PP20VB. replaced it.
Q3200 replaced just in case. pads for both of these looked bad. Pitted, dull grey. Probably from heating up a lot?
U3100 replaced from identical donor board - no damage found underneath, but did find some weird glue-looking stuff. reflowed U3200.
Short is gone, machine now sits at 5.18V with 20 mAmp.
measurements | |
PP3V3_UPC_XA_LDO | 3,4V |
PP3V3_UPC_XA_SX | cant find |
PP1V8_UPC_XA_LDOA | 1,8V |
PP1V8_UPC_XA_LDOD | 1,8V |
PP3V3_UPC_XB_LDO | 3,37V |
PP3V3_UPC_XB_SX | |
PP1V8_UPC_XB_LDOA | 1,8V |
PP1V8_UPC_XB_LDOD | 1,8V |
PPBUS_G3H | 0V |
I'm not (ever) completely sure if my U3100 replacement was a sucess. I have no stencil yet and am not looking forward to putting solder balls one by one on one of these again to rule it out. Is there anything else I can check to verify if U3100/U3200 are working properly? Anything else to measure with these symptoms?
U3100: