JVC KD-S670 Service Manual page 18

KD-S670
LA4743B(IC321) : Power amp.
1.Block diagram
IN 1
+
0.22 F
TAB
IN 2
+
0.22 F
ST BY
+5V
ST ON
R.F
+
47 F
IN 3
+
0.22 F
N.C
PRE GND
IN 4
+
0.22 F
ON TIME C
+
22 F
1-18
11
1
12
Stand by
4
Switch
Ripple
10
Filter
15
25
13
14
Muting &
ON Time Control
16
Circuit
Vcc 1/2 Vcc 3/4
6 20
-
+
Protective
circuit
-
+
Mute
circuit
-
+
Protective
circuit
-
+
+
2200 F 0.022 F
OUT 1+
9
OUT 1-
7
PWR GND1
8
OUT 2+
5
OUT 2-
3
PWR GND2
2
Mute 10K
22
+
3.3 F
Low Level
Mute ON
OUT 3+
17
OUT 3-
19
PWR GND3
18
OUT 4+
24
OUT 4-
23
PWR GND4
24