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DP-4X DEFLECTION POWER SUPPLY SHUTDOWN OUTPUT DIAGRAM EXPLANATION
PAGE 01-08
DEFLECTION POWER SUPPLY SHUTDOWN OUTPUT CIRCUIT DIAGRAM EXPLAINED: (C)
(See the Deflection Power Supply Shutdown Output Circuit Diagram for Details).
PROT_OVP: Identified as (C).
EXCESSIVE DEFLECTION 115V B+ CURRENT DETECTION: Part of several Shutdown outputs to (C).
•
QP05 monitors RP34 current draw. RP34 is a 0.39 low ohm resistor. Normally the current draw isn’t
enough to turn on QP05 . However, if there is a problem, the current draw through RP34 increases caus-
ing an increase in the voltage drop across this resistor. If there is enough current the base voltage of QP05
will drop enough to turn on this transistor. When QP05 turns on, its collector goes high. This high will
fire zener diode DP36 and generate a high on the anode of DP37.
•
CP49 and RP37 prevent faults triggering of the shut down line due to High Voltage bounce by smoothing
out and fluctuations on the anode of DP36 .
•
DP37
cathode is connected the anode of
DP38
. This line is connected to the line labeled
PROT_OVP
and identified as (C) .
•
PROT_OVP is routed to the Deflection Side Power Supply Shutdown Diagram also identified as (C) .
EXCESSIVE DEFLECTION 115V B+ VOLTAGE DETECTION: Part of several Shutdown outputs to (C).
•
DP39 monitors the Deflection 115V B+ line via the Voltage divider consisting of RP38 and RP39 . If the
Deflection 115V B+ line goes too high, DP39 will fire and generate a high on the anode of DP37 .
•
DP37 cathode is connected the anode of DP38 . This line is connected to the line labeled PROT_OVP
and identified as
(C)
.
•
PROT_OVP Identified as (C) is routed to the Deflection Side Power Supply Shutdown Diagram also
identified as (C) .
SW -28 VOLT SHORTED or MISSING DETECTION: Part of several Shutdown outputs to (C).
•
SW -28V Shorted or Missing Detection
Monitored by
DP46
. If the
SW-28V
is shorted or missing, the cathode will be pulled high causing the
zener to fire. This high will be routed through DP47 . This line is connected to the line labeled
PROT_OVP and identified as (C) .
•
PROT_OVP Identified as (C) is routed to the Deflection Side Power Supply Shutdown Diagram also
identified as (C) .