Sony Walkman MZ-R900, Service Manual

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34
MZ-R900
•
IC801 CXD2671-202GA (SYSTEM CONTROLLER, DIGITAL SIGNAL PROCESSOR, 16M BIT D-RAM)
Pin No. Pin Name I/O Description
1
PAUSE KEY
I
Set key input terminal (
X
key input)
2 MIC SENSE O
Control signal output to the microphone amp (IC303) “H”: HIGH, “L”: LOW,
normally: “H”
3
XTEST
I
Input terminal for the test mode set up “L”: test mode (normally fixed at “H”)
4, 5
NC
O
Not used (open)
6
MCUVDD0
—
Power supply terminal (for microcomputer block) (+1.5V)
7
MIFVSS3
—
Ground terminal (for microcomputer I/F)
8
XRST
I
System reset signal input terminal from the power control (IC901) “L”: reset
9 S MON I Servo signal monitor input terminal (A/D input) from RF amp (IC501)
10 VB MON I Voltage monitor input terminal of UNREG power supply (A/D input)
11 CHG MON I Charge voltage monitor input terminal (A/D input) from XPC18A22FCR2 (IC601)
12 VREF MON I Clear reference voltage input terminal (A/D input) from RF amp (IC501)
13, 14
SET KEY 1,
SET KEY 2
I Set key input terminal (A/D input)
15 VL MON I VL voltage monitor input terminal (A/D input)
16 HIDC MON I HIGH DC voltage monitor input terminal (A/D input)
17 WK DET I Set key start switching detection signal input terminal (A/D input)
18 REC KEY I REC key input terminal (A/D input)
19
HALF LOCK
SW
I
Open button detection switch (S805) input terminal (A/D input) “L”: when normal position,
“H”: when locked
20 RMC KEY I Key input terminal (A/D input) of the remote commander attached headphone
21 AVDD — Power supply terminal (for the analog circuit block) (+2.8V)
22 AVSS — Ground terminal (for the analog circuit block)
23 VDIOSC — Power supply terminal (for OSC cell) (+2.4V)
24 OSCI I System clock (45.1584MHz) input terminal
25 OSCO O System clock (45.1584MHz) output terminal
26 VSIOSC — Ground terminal (for OSC cell)
27 DAVDD — Power supply terminal (for the built-in D/A converter) (+2.4V)
28 VREFL I Reference voltage input terminal (for the internal D/A converter L-CH)
29 AOUTL O Built-in D/A converter (L-CH) output terminal Not used (open)
30 AOUTR O Built-in D/A converter (R-CH) output terminal Not used (open)
31 VREFR I Reference voltage input terminal (for the built-in D/A converter R-CH)
32
DAVSS
—
Ground terminal (for the built-in D/A converter)
33
ASYO
O
Playback EFM duplex signal output terminal
34 ASYI I Playback EFM comparison slice level input terminal
35
AVD1
—
Ground terminal (for the analog) (+2.4V)
36
BIAS
I
Bias input for the playback EFM comparison
37
RFI
I
Playback EFM RF signal input from RF amp (IC501)
38
AVS1
—
Ground terminal (for the analog)
39 PCO O Phase comparison output for the master clock of playback EFM system master PLL
40
PDO
O
Phase comparison output for the analog PLL Not used (open)
41
FILI
I
Filter input for the master clock of the playback EFM system master PLL
42 FILO O Filter output for the master clock of the playback EFM system master PLL
43 CLTV I Internal VCO control voltage input for the playback EFM system master PLL
44 PEAK
I
Peak hold signal input of the light amount signal (RF/ABCD) from RF amp (IC501)
45 BOTM
I
Bottom hold signal input of the light amount signal (RF/ABCD) from RF amp (IC501)
46 ABCD I Light amount signal (ABCD) input from RF amp (IC501)