Block Diagram; Components Description - Kenwood KAC-6403 Service Manual

KAC-6403
AUDIO UNIT (X09-8542-70)
IC2
J1
ISOLATION
L
AMPLIFIER
LINE IN A
IC2
ISOLATION
R
AMPLIFIER
IC4
ISOLATION
L
AMPLIFIER
LINE IN B
IC4
ISOLATION
R
AMPLIFIER
J2
SPEAKER
INPUT
+6dB
AUDIO UNIT (X09-8542-70)
Ref. No Application / Function
IC1 Buffer AMP
IC2 Isolation AMP
IC3 Buffer AMP
IC4 Isolation AMP
IC5 LPF
IC6 -3dB ATT
IC7 Buffer AMP
IC9 Phase inverter
IC13 DC/DC converter
Q3,4 Constant voltage power supply
Q5,6 DC/DC converter
Q7~10 DC/DC converter
2

BLOCK DIAGRAM

VR1 C151,153,R165,167
IC9
HPF
80Hz 12dB/OCT
+1
Ach
INPUT
GAIN
C152,154,R166,168
CONT.
IC9
HPF
80Hz 12dB/OCT
-1
VR2
S3
S1
Bch
INPUT LPF+10dB
GAIN 80Hz 12dB/OCT
CONT.
S1 S3
A-AB
Q3,4
15V
AVR
0dB

COMPONENTS DESCRIPTION

Amplifies 6dB by decreasing impedance.
Decreases common mode noise.
Amplifies 6dB by decreasing impedance.
Decreases common mode noise.
B-Rch side is phase inverter.
B-Lch side is buffer amplifier.
Decreases impedance.
A-Lch side is buffer amplifier.
Oscillates and controls DC/DC converter.
Controls ±15V constant voltage.
Switching FET.
Drives Q5's and Q6's gates.
Q101,102,
201,202
IC7
S2
+1
-3dB ATT
IC7
S2
+1
-3dB ATT
MUTE
IC6
S3
IC5
+1
-3dB ATT
IC5
S3
-1
-3dB ATT
L2 Q115-118,215-218
DC/DC DC DETECT &
CONVERTER OVER ROAD PROTECTION
Q605
P.CON
CIRCUIT
TH1 IC13
THERMAL OVER VOLTAGE
PROTECTION PROTECTION
Operation / Condition / Compatibility
Q103-114,
119-126
J9
POWER
L
AMPLIFIER
SPEAKER
Q103-114,
OUT A
119-126
POWER
R
AMPLIFIER
Q203-214,
219-226
POWER
L
AMPLIFIER
SPEAKER
Q203-214,
OUT B
219-226
POWER
R
AMPLIFIER
P.CON
BATTERY
+29.5dB