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820-00145 A1534

T

tipoti

Member
The device is charging, but the USB is not working. The USB voltage indicator does not light up at all. I tried using a flash drive, but its light is also not turning on, indicating that there is no USB 5V power. Where should I check next? I have already tested the DC socket and the intermediate flex cable.
 
T

tipoti

Member
"The voltage value on pins 2 and 52 of the J4700 is not stable; it fluctuates between 0.80V, 0.90V, and 1.1V. Shouldn't there be a constant 5V here?"
 
2informaticos

2informaticos

Administrator
Staff member
I suppose you have 820-00045 board in fact.

An USB device is powered from L7850; through U7860/65, depending which way the device is connected.
 
T

tipoti

Member
820-00045 Yes

PP5V1_S4SW : 5 volt
PP5V1_S4SW_CC1/CC2 : not stable; it fluctuates between 0.80V, 0.90V, and 1.1V.
u7860 Is the u7860 faulty?

If I jumper between PP5V1_S4SW and PP5V1_S4SW_CC1 will it work?
Will it work if I connect PP5V1_S4SW with PP5V1_S4SW_C? :)
 
2informaticos

2informaticos

Administrator
Staff member
Only one of U7860/65 works at a time; depending of the connection way.

Check BBPD_VCONN1/2_EN signals.
At least one should be high, when external USB device is connected.
If not, change U4700.

If use USB-C hub, then power it externally.
 
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