SRF-M85 - Sony Audio Service Manual (repair manual). Page 8

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SRF-M85
8
8
SRF-M85
SECTION  4
DIAGRAMS
Note for Printed Wiring Boards and Schematic Diagrams
Note on Schematic Diagram:
All capacitors are in 
µ
F unless otherwise noted. (p: pF)
50 WV or less are not indicated except for electrolytics
and tantalums.
All resistors are in 
 and 
1
/
4
 
W or less unless otherwise
specified.
C
: panel designation.
A
: B+ Line.
H
: adjustment for repair.
Power voltage is dc 1.5V and fed with regulated dc power
supply from battery terminal.
no mark : FM
(
) : AM
Voltages are taken with a VOM (Input impedance 10 M
).
Voltage variations may be noted due to normal produc-
tion tolerances.
Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal produc-
tion tolerances.
Circled numbers refer to waveforms.
Signal path.
F
: FM
f
: AM
Note on Printed Wiring Board:
X
: parts extracted from the component side.
Y
: parts extracted from the conductor side.
W
: indicates side identified with part number.
: Pattern from the side which enables seeing.
(The other layers' patterns are not indicated.)
Waveforms
– MAIN Board –
1
IC101 
wa
 (OSCOUT)
100 mV/DIV, 100 ns/DIV
91.5 ns
300 mVp-p
2
IC301 
1
 (XOUT)
200 mV/DIV, 5 
µ
s/DIV
13.3 
µ
s
520 mVp-p
3
IC301 
ta
 (OSCIN)
100 mV/DIV, 50 ns/DIV
91 ns
390 mVp-p
– KEY Board –
KEY BOARD  IC301  TC9349FAG-107 (S, D) (SYSTEM CONTROLLER)
Pin No.
Pin Name
I/O
Description
1
XOUT
O
System clock output terminal (75 kHz)
2
VDD
-
Power supply terminal (+1.5V)
3, 4
C1, C2
-
Connection terminal of capacitor for the CPU power supply voltage pressure up
5
VDB
-
Terminal for power supply voltage pressure up
6, 7
C3, C4
-
Connection terminal of capacitor for the liquid crystal display drive power supply voltage pressure up
8
VLCD
O
Voltage (+3V) output terminal for the liquid crystal display drive
9
VEE
O
Constant voltage (+1.5V) output terminal
10
VCPU
-
Power supply terminal for CPU
11, 12
INT1, INT2
I
Destination setting input terminal
13
POWER2
O
Power on/off control signal output for the radio system power supply    "L": power on
14
TEST
I
Not used
15 to 18
COM1 to COM4
O
Common drive signal output to the liquid crystal display
19 to 33
S1 to S15
O
Segment drive signal output to the liquid crystal display
34 to 36
KS1 to KS3
O
Key scan signal output for the key matrix
37 to 40
KR1 to KR4
I
Key return signal input for the key matrix
41
INT
I
Voltage detection signal input from the voltage detect   "L":Battery no-remainder
42
MEGA BASS
O
MEGA BASS on/off control signal output    "H": MEGA BASS on
43
BEEP
O
Beep sound drive signal output terminal
44
POWER1
O
Power on/off control signal output for the radio system power supply    "H": power on
45
BAND1
O
FM/AM band selection signal output terminal    "L": AM, "H": FM
46
BAND2
O
FM/AM band selection signal output terminal    "L": FM, "H": AM
47
MONO/ST
O
Monaural/stereo selection signal output terminal    "L": stereo, "H": monaural
48
HOLD
I
HOLD switch detect signal input terminal    "H": HOLD on
49
-
-
Not used
50
VPLL
-
Power supply terminal for PLL (+1.5V)
51
OSCIN
I
VCO input from the FM/AM RF amplifier
52
GND
-
Ground terminal for PLL
53
-
-
Not used
54
DO2
O
Phase comparator output terminal
55
-
-
Not used
56
MUTE
O
Muting on/off control signal output terminal    "L": muting on
57
DDCK
O
DC/DC converter pressure up clock signal output terminal
58
VDET
I
Pressure up voltage (+1.0V) detection signal input terminal
59
R-ON
O
Division resistor on/off control signal output terminal    "L": on
60, 61
-
-
Not used
62
RESET
I
System reset signal input from the reset signal generator    "L": reset
For several hundreds msec. after the power supply rises, "L" is input, then it changes to "H"
63
GND
-
Ground terminal
64
XIN
I
System clock input terminal (75 kHz)
IC Pin Function Description
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