SONY XRC4120
Service Manual

Pin No. 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

Pin Name AMP ON PLL-CKO PLL-CE PLL-SO PLL-SI LCD-SO LCD-CE LCD-CKO VOL-SIO NCO VOL-CKO ACC-IN MUT NCO AMSON N/R-OUT

I/O O O O O I O O O I/O O O I O O O O

Function Standby on/off control signal output to the power amplifier (IC751) �L�: standby mode, �H�: amp on PLL serial data transfer clock signal output to the FM/AM PLL (IC21) PLL chip enable signal output to the FM/AM PLL (IC21) PLL serial data output to the FM/AM PLL (IC21) PLL serial data input from the FM/AM PLL (IC21) Serial data output to the liquid crystal display driver (IC901) Chip enable signal output to the liquid crystal display driver (IC901) Two-way data bus with the electrical volume (IC331) Not used (open) Bus clock signal output to the electrical volume (IC331) Accessory detect signal input terminal Not used (open) Tape auto music sensor control signal output to the CXA2509AQ (IC301) �L� is output to lower the gain for audio level at FF/REW mode Forward/reverse direction control signal output to the CXA2509AQ (IC301) �L�: forward direction, �H�: reverse direction METAL control in/out terminal At initial mode: valid/invalid selection input of METAL function (valid at �L� input) At normal mode: METAL on/off control signal output to the CXA2509AQ (IC301) (METAL on at �H� output) Tape muting on/off control signal output to the CXA2509AQ (IC301) Active at ATA, FF/REW mode �H�: muting on �L�: accessory on �H�: muting on Audio line muting on/off control signal output terminal �H� active Serial data transfer clock signal output to the liquid crystal display driver (IC901) �H� active

53

MTLON

I/O

54

TAPE-MUT

O

55

DOLON

I/O

Dolby control in/out terminal At initial mode: valid/invalid selection input of dolby function (valid at �L� input) At normal mode: dolby on/off control signal output terminal (dolby on at �H� output) Not used this function (fixed at �H�) Whether a music is present or not from CXA2509AQ (IC301) is detected at auto music sensor �L�: music is present, �H�: music is not present Not used (open) 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 Station detector detect input from the FM/AM tuner unit (TU1) Stop level for SEEK, BTM, etc. is determined SD is present at input of �H� Dial pulse input of the rotary encoder (RE900) (for VOLUME/BASS/TREBLE/BALANCE/FADER control) A/D converter power control signal output terminal When the KEYACK (pin @§) that controls reference voltage power for key A/D conversion input is active, �L� is output from this terminal to enable the input Power select switch (S501) input terminal �L�: off (halt mode), �H�: on (operation mode) Power on/off control signal output of the illumination LED and liquid crystal display driver (IC901) �H�: power on Depends on initial setting of power select switch (S501) Power select switch (S501) on: �H� output at the accessory on Power select switch (S501) off: �H� output at the power on Rotation detect signal input from supply reel sensor and take-up reel sensor on the deck mechanism

56 57 to 75 76

AMSIN NCO ST-MONO

I O I/O

77 78 79 80 81

SD-IN RE-IN0 RE-IN1 AD-ON POWSEL

I I I O I

82

ILL-ON

O

83

REEL

I

� 32 �