NAD C 542 Ic Block Diagram, MAIN BOARD U101 CXA2581N, U202 BA6392FP, U403 TC74HC00AP, Main Board

IC BLOCK DIAGRAM

MAIN BOARD

U101: CXA2581N

LD

PD

SW

E

F

D

C

B

A

1

2

12

11

10

9

8

7

6

Vcc

22

Vcc

APC

D

A

B C

VOFST

gm

gm

RW/ROM

ACAC SUM VCA

GND

VC

VC

VC

AC_SUM

-

+

EQ_IN

VC

5

VC

(H/L) VC

-(Hi-OFFAPCZ) DVC

+

+

-

-

VOFST

RW/ROM

VOFST

+

-

RW/ROM

- +

43

RFG

RW/ROM

VC

DVC

BST

RFC

27 14

DVC + +

Vcc

RW/ROM -

DVC

RW/ROM

+

RW/ROM VC

DVC

VC

EQ

23242625

VFC

DVcc -18

EQ ON/OFF

DVC

VC

+

- +

- +

- +

VOFST

DVcc 21

RW/ROM

DVcc 17

DVcc

13

20

19

16

28

29

30

15

DVcc

CE

CEI

TE

TE BAL

FE

FEI

RFDCO

RFDCI

DC OFST

RFAC

MAIN BOARD

MAIN BOARD

U202: BA6392FP

U305, U306: OPA2134

CH1OUTF

1

28

GND

Out A

1

8

V+

CH1OUTR

2

F

27

CH4OUTF

-In A

2

A

B

7

OUT B

LEVEL

— +

+ —

RCIN1

3

SHIFT

26

CH4OUTR

+In A

3

6

_In B

REV

R

CH1RIN

4

25

VBIN

190K

INTER

V-

4

CH1FIN

5

FWD FACE

- +

24

VSIN

5

+In B

100K

VREFIN

6

23

VBIN

VREFOUT

7

+ -

22

VCC

MAIN BOARD

U403: TC74HC00AP

THERMAL

SHUTDOWN

CIRCUIT

A1

1

14

VCC

GND

8

21

VCC

CH2FIN

9

FWD

FWD 20

CH3FIN

B1

2

13

B4

INTER

INTER

CH2RIN

10

REV FACE

FACE REV

CH3RIN

R

R

19

Y1

3

12

A4

RCIN2

11

18

RCIN3

CH2OUTR

12

F

F

17

CH3OUTR

A2

4

11

Y4

CH2OUTF

13

DRIVE

16

CH3OUTF

B2

5

10

B3

GND

14

MUTE

15

MUTE

25K

25K

Y2

6

9

A3

GND

7

8

Y3

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