Sony XR-C7220R, Service Manual

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IC  PIN  FUNCTION  DESCRIPTION

•

 MAIN BOARD  IC600  MB90574PFV-G-210-BND (SYSTEM CONTROLLER)

Pin No.

Pin Name

I/O

Function

1

SEEKOUT

O

Seek control signal output to the FM/AM tuner unit (TUX10)
AM mode: Used for IF count output/SD output request/AGC cut at SEEK or BTM
FM mode: Used for SD speed up at SEEK, BTM, or AF
“L” is output at tuner off

2

AF-SEEK

O

PLL low-pass filter time constant selection signal output at AF SEEK
“H” is output when AF SEEK

3

WIDE

O

4

ST-MONO

I/O

FM stereo broadcasting detection signal input from the FM/AM tuner unit (TUX10), or forced 
monaural control signal output to the FM/AM tuner unit (TUX10)
“L” is input in the FM stereo mode, or “L” is output in the forced monaural mode

5

TUNMUTE

O

Muting on/off control signal output of the FM and AM tuner signal    “H”: muting on

6

FM-ON

O

FM system power supply on/off control signal output to the BA3918 (IC502)
“L”: AM power on, “H”: FM power on

7

TU-ON

O

Tuner system power supply on/off control signal output to the BA3918 (IC502)
“H”: tuner power on

8

VCC

—

Power supply terminal (+5V)

9

CSV-RST

O

Reset signal output to the CSV     “L”: reset    Not used (open)

10

BUS-ON

O

Bus on/off control signal output to the SONY bus interface (IC602)    “L”: bus on

11

SYSRST

O

Reset signal output to the SONY bus interface (IC602)    “L”: reset

12

DOORSW

I

Front panel open/close detection signal input    “L” is input when the front panel is closed

13

LCD SO

O

Serial data output to the liquid crystal display driver (IC900)

14

LCD CKO

O

Serial data transfer clock signal output to the liquid crystal display driver (IC900)

15

BEEP

O

Beep sound drive signal output terminal

16

LCD CE

O

Chip enable signal output to the liquid crystal display driver (IC900)    “H” active

17

UNISI

I

Serial data input from the SONY bus interface (IC602)

18

UNISO

O

Serial data output to the SONY bus interface (IC602)

19

UNICKO

O

Serial data transfer clock signal output to the SONY bus interface (IC602)

20

SD-IN

I

Station detector detect input from the FM/AM tuner unit (TUX10)
Stop level for SEEK, BTM, etc. is determined    SD is present at input of “H”

21

CSV-SO

O

Serial data output to the CSV    Not used (open)

22

CSV-CKO

O

Serial data transfer clock signal output to the CSV    Not used (open)

23

CSV-CE

O

Chip enable signal output to the CSV    “L” active    Not used (open)

24

SIRCS

I

Sircs remote control signal input from the remote control receiver (IC901)

25

PLLSI

I

PLL serial data input from the FM/AM PLL (IC10)

26

PLLSO

O

PLL serial data output to the FM/AM PLL (IC10)

27

PLLCKO

O

PLL serial data transfer clock signal output to the FM/AM PLL (IC10)

28

PLLCE

O

PLL chip enable signal output to the FM/AM PLL (IC10)    “H” active

29

ILL-ON

O

30

DIMMER

I/O

Dimmer control in/out terminal
At initial mode: The presence of dimmer select function is set (if this status, if “L” is input, the 
dimmer select function is present)
At normal mode: LCD back light brightness control signal output

31

TIR-IND

O

LED drive signal output of the TIR indicator    “H”: LED on    Not used

Power on/off control signal output of the illumination LED and liquid crystal display driver 
(IC900)    “H”: power on    Depends on initial setting of power select switch (S600)
Power select switch (S600) on: “H” output at the accessory on
Power select switch (S600) off: “H” output at the power on

IF band select signal output to the FM/AM tuner unit (TUX10)    “H”: wide mode
In receiving FM signals, interference noise from adjacent stations is removed by narrowing the 
IF band automatically in the tuner unit so as to raise the selectivity, but in this case, the distortion 
may increase and accordingly, the IF band is widened forcibly