Sony MD Walkman MZ-E25, Service Manual

Page: 23 / 30

– 29 –
•
MAIN BOARD IC801 RU6715MF-0007 (SYSTEM CONTROLLER)
Pin No. Pin Name I/O Function
1 CHG MON I
Charge voltage monitor input terminal Not used (fixed at “L”)
2 UREG MON I
Un-regulator voltage monitor input terminal
3 VTEMP I Temperature sensor detection signal input from the RF amplifier (IC501)
4 VREF I
Reference voltage (+1.25V) input from the RF amplifier (IC501)
5 PLAY KEY I
Inputs of
(
PLAY key on the switch unit “L” active
6 OPEN/CLS SW I
Upper panel open/close detection input from the open/close detect switch (S801)
“L”: close, “H”: open
7 RMC KEY I
Key input from the headphone with remote commander
8 SET KEY I
Inputs of
p
STOP,
+
/
=
FF/REW and /– keys on the switch unit (A/D input)
9 XRESET I
System reset signal input from the MPC1830VMEL (IC901) “L”: reset
For several hundreds msec. after the power supply rises, “L” is input, then it changes to “H”
10 AVDD —
Power supply terminal (+3V) (analog system)
11 AVSS —
Ground terminal (analog system)
12 TYPE 0 I Destination setting terminal (fixed at “H”)
13 TYPE 1 I
Destination setting terminal (fixed at “H”)
14 HOLD SW I
Hold switch (S802) input terminal “H”: hold on, “L”: hold off
15 MODEL I Destination setting terminal (fixed at “L”)
16 TYPE 2 I
Destination setting terminal (fixed at “L”)
17 VREG CON O
+2.5V power supply on/off control signal output to the optical pick-up driver (IC551)
“H”: power on
18 XWK CLR O Enable signal output to the optical pick-up driver (IC551) and MPC1830VMEL (IC901)
19 SLEEP O
System sleep control signal output to the MPC1830VMEL (IC901) “H”: sleep on
20 MCK I
Master clock input from the D/A converter (IC301)
21 NC O
Master clock output terminal Not used (open)
22 VDD —
Power supply terminal (+3V) (digital system)
23 SXIN I
Sub system clock input terminal Not used (fixed at “L”)
24 SXOUT O
Sub system clock output terminal Not used (open)
25 VSS — Ground terminal (digital system)
26 UREG CHK CON O
Un-regulator voltage monitor control signal output terminal Not used (open)
27 DSP SINT I
Interrupt signal input from the D.S.P. (IC601)
28 DBB OFF I
Digital mega-bass on/off detection input from the DIGITAL MEGA BASS switch (S301)
“H”: digital mega-bass off
29 AVLS SW I
AVLS (Automatic Volume Limiter System) switch (S805) input terminal
“L”: limit, “H”: normal
30 OPR LED O Operation LED (D801) drive signal output terminal “H”: LED on
31 NC O
Not used (open)
32 ADJUST I
Setting terminal for the test mode “L”: test mode, “H”: normal mode
33 NC O Not used (open)
34 SBUS CLK O
Serial data transfer clock signal output to the RF amplifier (IC501) and D.S.P. (IC601)
35 SBUS DATA O
Serial data output to the RF amplifier (IC501) and D.S.P. (IC601)
36 FR CAP I
Free-run counter capture input terminal
37 SLD 1 MON I Sled servo timing signal input terminal
38 SLD 2 MON I
Sled servo timing signal input terminal
39 CLV VCON O
Spindle servo drive voltage control signal output to the optical pick-up driver (IC551)
40 V28 CON O Error correction control signal output for the power supply voltage Not used (open)
41 APC REF O
Laser automatic power control signal output to the RF amplifier (IC501)
42 CLV U MON I
Spindle servo (U) timing signal input from the optical pick-up driver (IC551)