NEC NP-NC900C-A Service Manual page 38

Fan Driver BD – E side
CN9820 From SLAVE uC BD (J10)
Note: Pin to Pin
12V
12V
GND
5V
GND
I2C_SCL
I2C_SDA
FAN_Driver BD_Flag
–
–
–
CN9821 for Fan7
FG1
Vout
GND
CN9822 for Fan12
FG1
Vout
GND
–
CN9823 for Fan13
FG1
Vout
GND
–
–
CN9824 for Fan11
FG1
Vout
GND
–
–
–
"Confidential, Do Not Duplicate without written authorization from NEC."
TROUBLESHOOTING
1
f 12V Input
2
3 – GND
4 f 5V Input
5 – GND
6 f
I2C communication between uC BD and Fan Driver BD
7 n
If FAN actual RPM is out of the programmed value, ALERT pin
8 g
goes low.
9 – –
10 – –
11 – –
1 f FAN Speed indication. (Pluse)(5V)
2 g Fan voltage out
3 – GND
1 f FAN Speed indication. (Pluse)(5V)
2 g Fan voltage out
3 – GND
4 – –
1 f FAN Speed indication. (Pluse)(5V)
2 g Fan voltage out
3 – GND
4 – –
5 – –
1 f FAN Speed indication. (Pluse)(5V)
2 g Fan voltage out
3 – GND
4 – –
5 – –
6 – –
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