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MD-R3H
WAVEFORMS OF CD CIRCUIT
1
2
100
90
10
0%
Potential difference 0V
Disc free from flaw
[Disc playback mode]
2V/1mS (DC range)
IC700
,
0%
10
90
100
Potential difference 0V
Disc having flaw
(the same as above)
If a flaw exists, pulse-like
noise appears as shown
right.
Noise appears also in
output of and TE or
FE signal.
11 12
0%
10
90
100
Potential difference 0V
[Disc playback mode]
0.5V/0.5mS
IC700
,
(Dc range)
9
100
90
10
0%
1/2VCC
[Disc playback mode]
50mV/2mS
IC750
3
10
0%
90
100
[Disc playback mode]
0.2V/0.5
µ
S
TP751
(AC range)
4
100
90
10
0%
1/2VCC
In test mode 3
0.2V/1mS
TP751
(DC range)
1/2VCC
90
10
0%
100
[Disc playback mode]
0.2V/1mS (DC range)
22
100
90
10
0%
TRIG
200mV/0.5S (DC range)
1/2VCC
* Observation with the aid
of storage oscilloscope
Only the triangular wave
and luminous dot shown
right are observed on oscillograph.
In test mode 2
(disc is not loaded.
Lens is moved up and down.)
IC750
37 38
100
90
10
0%
GND
GND
PWM2
PWM1
[Disc playback mode]
(Use the 10:1
probe.)
0.2V/10
µ
S
(DC range)
Disc motor
PWM output
IC800
,
19
100
90
10
0%
[Disc playback mode]
(Use the 10:1 probe.)
20mV/0.5
µ
S
IC800
(AC range)
28
100
90
10
0%
GND
2V/0.1
µ
S (DC range)
[Disc playback mode]
IC800
4
100
90
10
0%
* If disc has flaw or during track
search pulse-like "L" level appears
as shown below.
When the disc rotates and
the HF signal is
synchronized with the IC
internal signal, H level is
set.
Playback mode, 4.8V
Stop mode, 0V
2Vdiv (DC range)
IC800