Sony KV-13FS100 Product & Training Manual page 37

The next diagram (Figure 7-3) shows the audio circuit configuration for the models KV-20FS100, KV-24FS100
and KV-13FS100/110 where IC400 audio processor is not installed. These models use IC401 for stereo audio
input switching and IC404 for volume control and audio amplification. IC401/pins 2 and 4 (switching inputs) are
controlled using a simple two binary signal from IC001/pins 67 and 68. Table 7-2 shows the state IC401/pins 2
and 4 depending on the input selected.
FIGURE 7-3 - AUDIO CIRCUIT [KV-20FS100, KV-24FS100 & KV-13FS100/110]
Table 7-2 - IC401(IC402)/pins 2 and 4 Input Select States
Input
Tuner (TV)
Video 1
Video 2
Video 3 (YUV)
(IC401 Only)
DC voltage using D410, C499 and R498. The level of this DC voltage depends on the pulse duration of the PWM
signal, which is modified by IC001, and ultimately the user volume setting. The DC is applied to IC404/pin 9 and
is finally used to set the audio level output on IC404/pins 2, 4, 10 and 12.
L 1
TV-L
TUNER
TV-R
R 6
J200
L 3
VIDEO 1
7
R
J202
L 5
YUV-L
AUDIO IN
R 8
YUV-R
J201
L 9
VIDEO 2
R 13
S2
FROM IC001
PIN 68
(0-SEL 1 )
FROM IC001
PIN 68 (0-SEL 0 )
IC401/pin 2 (S2)
Low
High
Low
High
IC401
C457
R-OUT
11
8
V1-L
V1-R
C458
L-OUT 15
6
V2-R
STBY 5V
V2-L
S1 V+
R036
2 4 14
D410
9V
FROM IC001
PIN 62
(0-VOL )
IC401/pin 4 (S1)
Low
Low
High
High
35
14V
PS401
1
VA
12
+
IN -R
-
10
IC404
2
+
IN -L
-
4
VC
9
R498
C499
7.3CTV30 1445 3/8/02
7. Audio