Sony WRT-822B, Service Manual

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5-5
WRT-822B
PIN SIGNAL I/O DESCRIPTION
1 to 20 S31 to S12 OUT LCD segment control
21 to 24 COM0 to COM3 OUT LCD common control
25 BIAS OUT Power supply for LCD drive
(
+ 5.0 V)
26 to 28 VLC0 to VLC2 IN Power supply for LCD drive
29 to 31 ATT0 to ATT2 OUT AF ATT control
32 ID OUT ID
33 VSS — Ground
34 AFM OUT AF muting
35 LVD OUT Battery alarm
36, 37 — — NC
38 RXD IN Received data
39 — — Ground
40 TEST IN Test
41 — — Ground
42 POFF–IN IN Power off
43 + IN Channel switch +
44
_
IN Channel switch
_
45 SET IN SET switch
46 CLK OUT EEPROM/PLL Clock
47 DI OUT EEPROM/PLL data out
48 CS OUT EEPROM chip select
49 LAT OUT PLL latch
PIN SIGNAL I/O DESCRIPTION
50 POFF–OUT OUT Power off
51 REM OUT RF muting
52 DO IN EEPROM data in
53 LD IN PLL lock
54 to 57 — — NC
58 BAT0 IN VDD ( + 5.0 V)
59 BAT1 IN Battery voltage
60 DEST IN Selection for destination
61 ALO IN AF level
62, 63 — — Ground
64 AVSS — Ground
65 AVREF IN A/D convertor reference
voltage
66 VDD — VDD ( + 5.0 V)
67, 68 XT1, XT2 IN 32.768 kHz
69 IC IN VDD ( + 5.0 V)
70, 71 X1, X2 IN 4 MHz clock
72 RESET IN Reset
73 SEL IN VSS (Ground)
74 to 78 — — NC
79 TXD OUT Transmitted data
80 SLP OUT SLP
CPU Pin Description : IC402
UPD753036GK
—TOP VIEW—
61
66
69
80
GND
NC
NC
GND
40
33
21
GND
GND
V
DD ( + 5 V)
NC
NC
NC
NC
NC
60 41
1
20
V
DD
(
+
5 V
)
NC NC NC NC
GND
IC