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MHC-V7D
27
Switching Regulator Diagnosis Flow
SECTION 5
TROUBLESHOOTING
The Output from Switching regulator is checked.
Is following power voltage up to standard?
Standby
CN4
CN2
pin1
pin2-4
pin5
pin7
pin8-10
pin1
AC
IN
Ye
s
No
Ye
s
END
No
Check whether the state of the Cable and Outlet are normal.
If there are no problems, check circumference circuit for
Main on/Sub on Output of the Motherboard mount side.
Replaces Switching regulator if it is not up to standard.
The Power Control signal to Switching regulator is checked.
Is following power voltage OK?
Main on/Sub on
CN 4 :pin8
13.5V
±
0.5V
0V
0V
0V
0V
0V
13.5V
±
0.5V
0V
0V
0V
0V
0V
13.5V
±
0.5V
-62.5V±5%
-25.5V±5%
+25.5V±5%
+62.5V±5%
-45.5V±10%
(1) AC
input
(2) Fuse
(3) Sub Power transformer
(4) CN 4 Connector
pin1: Audio (13.5V)
pin2: Audio (GND)
pin3-4: LED (13.5V)
pin5-6: LED (GND)
pin7:
AC-Det
pin8:
PCON
pin9: LOW AC
(5) MAIN Power transformer
(6) CN 2 Connector
pin1: SPV (DC-45.5V)
pin2-4:
-PVDD
(DC-62.5V)
pin5: -VL (DC-25.5V)
pin6:
GND
pin7: +VL (DC+25.5V)
pin8-10:
+PVDD
(DC+62.5V)
Hi (3.3V)
Power On
Demo mode
Low (0V)
Low (0V)
Standby
Power On
Demo mode
(6
)
(5
)
(2
)
(1
)
(3
)
(4
)
Содержание MHC-V7D
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