Sony MDX-C7900, Service Manual

Page: 45 / 62

– 63 –
Pin No. Pin Name I/O Function
85 PLL CE O PLL serial chip enable output to the FM/AM PLL (IC100)
86 HSTX I Hardware standby input terminal Not used (open)
87 MD2 I Mode selection input terminal (fixed at “L”)
88 MD1 I Mode selection input terminal (fixed at “H”)
89 MD0 I Mode selection input terminal (fixed at “H”)
90 RESET I
System reset signal input from the reset signal generator (IC801) and reset switch (S900)
“L” is input for several 100 msec after power on, then it changes to “H”
91 VSS —
Ground terminal
92 X0
I Main system clock input terminal (3.68 MHz)
93 X1
O Main system clock output terminal (3.68 MHz)
94 VCC —
Power supply terminal (+5V)
95 PW SEL
I Power select switch (S700) input terminal “L”: on (operation mode), “H”: off (halt mode)
96 POL MONO I
Polar monaural detection signal input terminal Not used (open)
97 to 99 NC O
Not used (open)
100
BAND
(9K-10K)
I
Frequency select switch (S701) input terminal “H”: MW 9k step/FM 50k step, “L”: MW10k
step/FM 200k step Used for the E model only
101 NC O
Not used (open)
102 RAMBU I
103 NC O
Not used (open)
104 LCD CE
O Chip enable output to the liquid crystal display driver (IC801)
105 FLASH W I
Fixed at “H” in this set
106 REIN0
I Rotary encoder (EN801) input for volume/bass/treble/balance/fader control
107 REIN1
I Rotary encoder (EN801) input for volume/bass/treble/balance/fader control
108
LAMP ON
(ILL ON)
O
109 PW ON
O Main system power supply on/off control signal output to the BA3918 (IC800) “H”: power on
110
FM ON O FM system power supply on/off control signal output to the BA3918 (IC800) “H”: FM on
111
TUN ON O Tuner system power supply on/off control signal output to the BA3918 (IC800) “H”: tuner on
112 to 118
NC O
Not used (open)
119 VSS — Ground terminal
120
NC O
Not used (open)
Internal RAM reset detection signal input from the RN5VD23AA (IC802)
Input terminal to check that RAM data are not destroyed due to low voltage
This checking is made within 100 msec after reset
Power supply on/off control signal output terminal at the illumination and liquid crystal display
driver (IC801) “H”: power on
At power select switch (S700) on mode: “H” output at the accessory on
At power select switch (S700) off mode: “H” output at the power on