CONFIDENTIAL – DO NOT COPY Page 9-5

File No. SG-0198

Yes
N0
N0
Yes
N0
N0
N0
N0
N0
Yes
Yes
Yes
Yes

TROUBLE OF DC-DC CONVERTER

Start

J7 PIN10,11,12
J7 PIN 2,3,4
The voltage is about + 12V while
power switch on
1.J7 connection good
2.Check J7 Pin1 is up to 3V?
3.Check power board

The voltage is about + 5V

1.Check power board

2.Check power cable

connection J7
U1 pin 5 6 7 8
The voltage is about +5V while
power switch on
1.J1 connection good
2. Check U11 GPIO_7 Pin
U4 pin2
The voltage is about +3.3V
1.J1 to connection good?
2.Check U4
U6 pin 2
The voltage is about +3.3V
1.J1 to connection good?
2.Check U6
U8 pin2
The voltage is about +3.3V
while power switch on
1.Check J1 Connect
2.Check U8
U5 pin2
The voltage is about +1.8V while
power switch on
1.Check U5

END

U7&U8&U10 pin2
The voltage is about +1.8V
while power switch on
1.Check J1 Connect
2.Check U7&U8&U10