Sony WRT-847A, Service Manual

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5-5
WRT-847A/847B
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 RFM OUT RF muting
36 PO-H/L OUT RF power switch
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 DATA OUT EEPROM/PLL data out
48 CS OUT EEPROM chip select
49 LAT OUT PLL latch
50 — — NC
CPU Pin Description : IC202
UPD753036GK
PIN SIGNAL I/O DESCRIPTION
51 LVD OUT Battery alarm
52 DO IN EEPROM data in
54 FRC OUT EQ switch
55 TC OUT TC switch
56, 57 — — NC
58 — — Pull up
59 BAT1 IN Battery voltage
60 — — Ground
61 AFIND IN AF level
62 CU-ID IN Capsule ID
63 — — Ground
64 AVSS — Ground
65 AVREF IN A/D convertor reference
voltage
66 VCC2 — VDD (
+
3.3 V)
67, 68 XT1, XT2 IN 32.768 kHz
69 VCC2 IN VPP ( + 3.3 V)
70, 71 X1, X2 IN 4 MHz clock
72 RESET IN Reset
73 GND IN VSS (Ground)
74 BL OUT LCD Back-light
75 TONE-OFF OUT Tone switch
76 to 78 — — NC
79 TXD OUT Transmitted data
80 — — NC
—TOP VIEW—
61
66
69
80
GND
NC
GND
40
33
21
GND
GND
V
DD ( + 3.3 V)
V
PP ( + 3.3 V)
GND
NC
NC
NC
NC
60 41
1
20
V
DD
(
+
5 V
)
NC NC NC
GND GND
IC