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820-01700 no backlight + other issues
- Thread starter nininunz
- Start date
What is the exact resistance to ground on PPBUS_G3H?
Compare with values on all big coils; including L9080/580.
Compare with values on all big coils; including L9080/580.
nininunz
Member
What am I comparing on L9080? Like PP2V5_NAND_SSD1 to ground? to ppbus_g3h? to PP2V5_SW1_TPS62180_SSD1? Sorry for my ignorance.
ppbus_g3h to ground when I first touch its about 5ohms then drops to 3ohms after 2-3 seconds then settles around 2.5ohms, but when I hold it a long time (20+ seconds) it keeps creeping down, got down to 1.9 before I got too impatient after about a min.
ppbus_g3h to ground when I first touch its about 5ohms then drops to 3ohms after 2-3 seconds then settles around 2.5ohms, but when I hold it a long time (20+ seconds) it keeps creeping down, got down to 1.9 before I got too impatient after about a min.
nininunz
Member
I'm an idiot, I really do apologize for wasting your time. A jumper I ran some time ago came loose when I was cleaning corrosion in the area and it seems I soldered it one pad over from where it should've been, a ground pad :|
Now to tackle yet another issue I created on this board. Some components by U4900 and U4920 blew away when I was removing U4920 to clean up a corrosive mess.
Now to tackle yet another issue I created on this board. Some components by U4900 and U4920 blew away when I was removing U4920 to clean up a corrosive mess.
0.1 ohm shouldn't be through an high-side MOSFET, or power IC.
However, check first if you don't exact same short on any coil; don't forget L9080/580.
If none of them gives such short, then is safe to inject voltage into PPBUS_G3H.
Anyway, start with 1V and slowly increase if needed.
Set amp current to max first.
However, check first if you don't exact same short on any coil; don't forget L9080/580.
If none of them gives such short, then is safe to inject voltage into PPBUS_G3H.
Anyway, start with 1V and slowly increase if needed.
Set amp current to max first.