Sanyo DC-DA370 service manual IC440 AN7348K Play/Rec Pre Amp IC443 BA7755A Head Switch

IC BLOCK DIAGRAM & DESCRIPTION

IC440 AN7348K ( Play/Rec Pre Amp)

IC443 BA7755A (Head Switch)

L-PB AMP

R-PB AMP

L-PB NF

L-PB EO

L-PB AMP OUT

ALC

L-REC IN

L-REC OUT

ALC

HI/LO

CRO/NOR

VCC

24

23

22

21

20

19

18

17

16

15

14

13

P

R

ALC

P

A/Rec

R

B

Mute

Rec

PB Amp(L)

Amp(L)

Nor/Cro

& Hi/Lo

Logic

PB Amp(R)

Rec

1

2

3

4

5

A/Rec

Mute

Amp(R)

B

Logic

R

P

Ripple

VCC

HEAD

GND

CTRL2

CTRL1

SWITCH

A/B

Rejection

Logic

Rec/PB

1

2

3

4

5

6

7

8

9

10

11

12

L-PB AMP

R-PB AMP

R-PB NF

R-PB EO

R-PB OUT

AB SW

R-REC IN

R-REC OUT

REC/PB SW

A/B SW

FILTER

GND

IC445 MM1453XF (Q Xpander with Spread Control)

IC442 TDA7269 ( Stereo Amplifier)

VCC

LIN

VREF

QF1

QF2

QF3

QF4

QF5

QF6

VSS

18

17

16

15

14

13

12

11

10

3

MUTE

5

IN-L

7

+

4

OUT-L

VIRTUAL AUDIO

-

Bias

QXpander

8

IN-L

PROCESSOR

GND 9

10

IN-R

IN-R

11

-

2

OUT-R

+

1

2

3

4

5

6

7

8

9

1

6

RIN PNR S/Q DET

QIN

SPC ROUT LOUT

GND

IN-R

IN-R

IC231 LA1844ML ( Tuner System)

24

23

22

21

20

19

18

17

16

15

14

13

ALC

AM

AM

AM

BUFF

OSC

MIX

RF.AMP

DECODER

PILOT

AGC

ANTI-BIRDIE

CANCEL

AM

AM

P-DET

STEREO

IF

DET

φ�

SW

LEVEL

AM/FM

DET

IF

COMP

S-CURVE

BUFF

VCO

FF

FF π� FF

PILOT

TUNING

304kHz

38k

19k∠�2

19k∠�

DET

FM

IF

FM

DRIVE

DET

REG

GND

VCC

1

2

3

4

5

6

7

8

9

10

11

12

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