Power Fail Circuit - Olivetti ECR 7100 Service Manual

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4-6 POWER FAIL CIRCUIT

A circuit using point the Collector of transistor Q3 generates power fail.
When power is ON and system is operating normally, the power fail signal stays at a high level
Q2
C 2SC3242 E
R22
3.3K
C9
ZD1
HZ6C3TA-E
0.1uF
50
VCC
EC4
+
D7
10uF_16V
1N4148
D8
A K
1N4148
R27
4.7K
EC3 ZD2
HZ5B1
+
10uF_16V
R26
B Q3
2SC1815
100
R23
330
ECR7100 Service Manual
PF
VBB
K
+ EC5
10uF_16V
C2
0.01uF
.
D9
A
1N4148
D20
JUMPER
CN2
2
1
B2B-XH-A
Y110910 - 8
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