Printronix P9012 Maintenance Manual page 45

TEST TIMING
FAULT
MONITOR #1
HAMMER
DRIVER (H/D)
+12V RTN
+5V
–12V
REGULATOR
HAMMER
OUTPUT
+36V
DISABLE
CIRCUITS
Q
+5V
HMC
Q
NHCK
HRS
NUD
OPTO–
COM IN
ISOLATORS
NHSC
Principles of Operation
OD
5HL
SD
OE
HCK
HRS
OD
COM IN
NHSC
D
CK
Figure 2–19. Hammer Driver Block Diagram
t t
DARLINGTON DRIVERS
t t
DATA LATCHES
SHIFT REGISTER
CK
OPTO–
Q
ISOLATOR
+36V
t t
FAULT
MONITOR #2
–12V
(33)
(33)
(33)
COM OUT
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