Sony MDX-C8900R, Service Manual

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MAIN BOARD IC500 MB90574PFV-G-131-BND (MASTER CONTROLLER)
Pin No. Pin Name I/O Function
1 SEEKOUT O
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
5 TU-ATT 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 (IC506)
“H”: FM power on, “L”: AM power on
7
TU-ON O
Tuner system power supply on/off control signal output to the BA3918 (IC506)
“H”: tuner power on
8 VCC —
Power supply terminal (+5V)
9
CSV-RST
O
Reset signal output to the RSC-164 (IC901) and flash memory (IC902) “L”: reset
10 BUS-ON
O
Bus on/off control signal output to the MD mechanism controller (IC501) and SONY bus
interface (IC504) “L”: bus on
11 SYSRST O
Reset signal output to the MD mechanism controller (IC501) and SONY bus interface (IC504) “
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 (IC504)
18 UNISO
O Serial data output to the SONY bus interface (IC504)
19 UNICKIO I/O
Serial data transfer clock signal in/out terminal with the MD mechanism controller (IC501) and
SONY bus interface (IC504)
20 CSV-SI I
Serial data input from the RSC-164 (IC901)
21
CSV-SO
O
Serial data output to the RSC-164 (IC901)
22
CSV-CKO
O
Serial data transfer clock signal output to the RSC-164 (IC901)
23
CSV-CE
O
Chip enable signal output to the RSC-164 (IC901) “H” active
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 (IC4)
26 PLLSO O
PLL serial data output to the FM/AM PLL (IC4)
27 PLLCKO O
PLL serial data transfer clock signal output to the FM/AM PLL (IC4)
28 PLLCE O
PLL chip enable signal output to the FM/AM PLL (IC4) “H” active
29
ILL-ON O
30 DIMMER I/O
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 (SW500)
Power select switch (SW500) on: “H” output at the accessory on
Power select switch (SW500) off: “H” output at the power on
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
Seek control signal output to the FM/AM tuner unit (TU1)
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
IF band select signal output to the FM/AM tuner unit (TU1) “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
FM stereo broadcasting detection signal input from the FM/AM tuner unit (TU1), or forced
monaural control signal output to the FM/AM tuner unit (TU1)
“L” is input in the FM stereo mode, or “L” is output in the forced monaural mode