No Sound, Noise Generated - Denon RCD-N9 Service Manual

2. No Sound, Noise generated

2.1. COMMON(signal)
Check Digital Audio Data output from CODEC.
MAIN PCB
•[IC22]： 17, 18, 19, 20pin
DIR_LRCK, DIR_SCLK, DIR_SDATA, DIR_MCLK
Check Digital Audio Data input for PWM CONTROLLER.
MAIN PCB
•[IC23]： 11, 22, 23, 24pin
MCLK, LRCK, SCLK, SDIN1
Check the PWM waveform output of PWM CONTROLLR AMP PCB
AMP PCB
•[WF72]： 2, 4pin (Lch)
8, 10pin (Rch)
Check the waveform of the terminals above when the input function
is "Analog" and in a state higher than "Volume 1".
If an approximate 3.3VP-P square wave can be confirmed at each
terminal, there are no problems with DIR (PCM9211) and the PWM
CONTROLLER (TAS5558).
2.1.C
Check PWM waveform of each terminal (Square wave).
Check the PWM output of IC70 (TAS5142).
•[L708]：TAS5142 side terminal +/- (Rch)
•[L709]：TAS5142 side terminal +/- (Lch)
A test terminal or cable needs to be attached to the bottom side of
the AMP board to measure the waveform of each terminal.
There are no faults in the IC70 (TAS5142) if an approx. 29VP-P square
wave is confirmed at each terminal.
No faults
Identify the input function from which sound is not output or from
which noise occurs, and check the troubleshooting sections from
"2.3" onwards.
OK
OK
OK
OK
NG
Check the solder and replace any faulty parts.
•[IC22]：17, 18, 19, 20pin on MAIN PCB
NG
Check the solder and replace any faulty parts.
•[IC23]：11, 22, 23, 24pin on MAIN PCB
2.1.A
PWM waveform (square wave) is not output.
NG
Fault in the DIR (PCM9211) or PWM CONTROLLER
(TAS5558). Check "2.2. COMMON (power supply, com-
munication line)", and replace the IC56 (TAS5558) if
there are no faults.
2.1.B
NG
PWM waveform (square wave) is disrupted.
Fault in IC70 (TAS5142).
Replace the IC70 (TAS5142).
If the fault still occurs after replacement, check "2.1.A".
NG
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