![background image](http://html.mh-extra.com/html/sharp/up-5700/up-5700_service-manual_373332093.webp)
3-3. +12V, –12V output section
The +12V/–12V output section supplies a stable voltage with the regulator IC (IC3, IC4). The overcurrent protection function is built in the regulator
IC.
3-4. ACL (instantaneous service interruption detection) signal
When the AC voltage becomes zero or when the input voltage is decreased so that the output voltage cannot be stabilized, the ALC signal is driven
LOW.
A voltage proportional to the AC input voltage is made with 9-10 pin winding of the transformer, and the voltage rectified and smoothed by D19 and
C26 is divided by R30, R31, and R32 to supply to IC5 2pin.
When this voltage becomes greater than the reference voltage (1.25V), IC5 6 pin output becomes HIGH.
3-5. PHSNS circuit
The PHSNS signal detects open/close of switch SW1. When SW1 is turned on, a current flows through 1-2 pin of PC2 to turn on 3-4 pin of PC2,
turning off Q4. Then the PHSNS signal becomes HIGH. When SW1 is turned off, PC2 turns off to drive the PHSNS signal LOW.
3-6. PHOLD signal
This signal is provided from the main PWB. When this signal is HIGH (+5V), Q5 turns on to turn on relay RLY1, turning off SW1. The AC input
voltage is supplied through RLY1 to stabilize the output voltage. When PHOLD signal becomes LOW, the relay turns off to stop the power.
8
13,14
9
10
D16
FMB26L
C20
330µF
35V
PW
(PY)(LXJ)
D15
1SS270A
3
2
1
IC3
C21
100µF
35V
PW(PY)
C22
104K
2
3
5
+12V
+12V
GND
D17
FMB29L
C23
330µF
35V
PW(PY)
(LXJ)
R43
1K
R44
120
C24
100µF
35V
PW(PY)
1
2
3
IC4
D18
C25
104K
GND
7
-12V
4
SI-3122N
UPC337H
(HF)
1SS270A
D19
AG01
R42
10 ERQ14AJ
C26
1µF
100V
PR
R29
100K
R32
7.5K
R30
36K
R31
36K
2
5
7
6
IC5
M51957BL
4
C27
0.47µF
50V PR
C28
103K
ACL
1
GND
T1
10Pin
R33
2.2K
+12V
R3
R4
R18
R19
24K
1/2W
24K
1/2W
24K
1/2W
24K
1/2W
R34
8.2K
R39
22
R35
2.7K
1
2
4
3
PC2
TLP721F
(TLP621)
R40
16K
C29
1µF
50V
PR
D9
HZM5.1B1
(RD5.1SB1
DTZ5.1A)
R38
1K
Q4
DTC114EUA
(RN1302)
PHSNS
12
C5
+12V
+5V
SW1
SDDJE
3071A
1
2
3
CNW1
CN7
1
2
3
B3P5-VH
CN1
GSK801/2DS
D20
1SS193
+5V
RLY1
G5PA-1
Q5
DTC114EUA
(RN1302)
PHOLD
11
6 – 3
Summary of Contents for UP-5700
Page 139: ...1 UP 5700 Main PWB CHAPTER 10 PWB LAYOUT A side 10 1 ...
Page 140: ...2 UP 5700 CPU PWB A side UP 5700 CPU PWB B side 10 2 ...
Page 141: ...3 UP 5700 KEY I F PWB A side CN2 UP 5700 KEY I F PWB B side 10 3 ...
Page 144: ...For components produced in January 1998 and onward Parts side Solder side 10 6 ...
Page 145: ...7 2 Sub PWB Side A Side B 10 7 ...