TM 5-6675-318-14
P r o d u c e s supply voltages of +15 V, +8 V, and
a. Power supply control circuit.
+5 V, which are used as control voltages within the power supply assembly itself.
RF1 filter, line
(1) Main ac power is input to PCA A9 via an ac receptacle,
a c power source is
fuses and a set of line voltage selector switches. The main
t h e LINE power switch
s w i t c h e d into the primary windings of transformer T1 through
S2 and S3. Power
a n d the appropriate settings of the line voltage selector switches
rectifier diodes CR1
transformer T1 provides the proper voltages to the full-wave
and CR2.
(2) The rectified output of CR1 and CR2 is filtered by capacitor C5 and
applied to voltage regulator A9-U1 which provides the regulated +15 V supply.
Capacitors A10-C3 and A10-C4 provide additional filtering and bypass for this
supply.
( 3 ) A second voltage regulator A9-U2 provides the +8 V supply using the
regulated +15 V supply as an input. Capacitors A10-C5 and A10-C6 provide additional
T h e +5 V (B) regulator A10-U2 functions in a
filtering and bypass for this supply.
s i m i l a r manner by using the regulated +8 V supply as an input. Capacitor A10-C7
provides additional filtering for this supply.
( 4 ) The +5 V, +8 V, and +15 V supply voltages are used only within the power
supply assembly and are not outputted to other portions of the plotter.
P r o d u c e s the +7 V, +5 V (A), +26 V, -26 V, +12 V,
b. Plotter power circuit.
a n d the -12 V supply voltages which are generated on PCA A9 card and regulated by
c i r c u i t r y o n P C A A 1 0 c a r d . T h e plotter power voltages are generated and regulated
by the following functional circuits:
Ac-to-dc conversion circuit
Square-wave
conversion
circuit
Voltage output smoothing circuit
Timing
sawtooth
generation
circuit
Voltage
turn-on
regulation
circuit
Turn-on/off sequencing circuit
Power-on detection generation circuit
Converts the main plotter ac power to dc.
(1)
Ac-to-dc
conversion
circuit.
(a) The main ac power source is connected to a full-wave bridge recti-
f i e r CR6-CR9 through the LINE power switch and coil L1. Line voltage selector
For 100/120 V ac
switch S4 setting determines the filter circuit configuration.
o p e r a t i o n , line voltage selector switch S4 connects the junction of C6 and C7 to the
junction of CR8 and CR9 which converts this filter network into a voltage doubler
configuration.
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