3-12
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output by DIGITAL AUDIO AMP DAMAGE, repair the set according to the following
guide.
5-2. BY DIGITAL AUDIO AMP DAMAGE (IN ALL FUNCTIONS)
5-2-1. Solution
Please check and replace IC700, IC701 on MAIN board.
5-2-2. How to troubleshoot (Countermeasure)
1) Check PWM_FL±, PWM_FR± & PWM_SW± signals from IC700 to IC701 each input function.
If no signal, check if I2S audio signals are entered to IC700.
Refer to “I2S audio signal interface” on Item 5-1.
2) Check PVDD.
If PVDD is abnormal, check the SMPS.
3) Check +12 V for driving the gate of AMP IC(IC701).
a. All the powers are normal, but if +12 V is low, there is possible for AMP IC to be damaged.
b. Remove L706 one. When removed a inductance, if +12 V is recovered, the IC connected to it was damaged.
c. Replace the IC with a new one.
4) Check the impedance between IC701_OUT_C/OUT_D & GND.
a. If the impedance is 0
Ω
, the IC must be damaged.
b. After removing the heat sink, replace it with a new one.
5-2-3. Service hint (Any picture/ Remark)
< Signal check point >
Summary of Contents for OM4560
Page 13: ...2 2 ...
Page 17: ......
Page 49: ...3 34 3 33 BLOCK DIAGRAMS 1 SYSTEM BLOCK DIAGRAM ...
Page 51: ...3 38 3 37 3 AUDIO PATH BLOCK DIAGRAM ...
Page 52: ...3 40 3 39 4 POWER BLOCK DIAGRAM ...
Page 55: ...3 64 3 63 2 MAIN P C BOARD TOP VIEW BOTTOM VIEW ...
Page 56: ...3 66 3 65 3 FRONT P C BOARD TOP VIEW BOTTOM VIEW ...
Page 58: ...3 70 3 69 ...