STV9555 ST Microelectronics, STV9555 Datasheet - Page 17

• Manufacturer Part Number: STV9555
• Description: 9.5 ns TRIPLE-CHANNEL HIGH VOLTAGE VIDEO AMPLIFIER
• Manufacturer: ST Microelectronics

10.9 Stand-by mode, spot suppression
The usual way to set a monitor in stand-by mode is to switch-off the Vcc (12V).
The STV9555 has an extremely low power consumption (I
and the outputs are set to low level (white picture).
To avoid the display of a spot effect during the switch-off phase, it is necessary to adjust the G1 circuitry
(Resistors Rx and Cx, see
Figure 19. Stand-by mode, spot effect
-120V
+80V
-30V
0V
Cathode
G1
EHT
(27kV)
Figure
Typical G1 generator circuitry
19) to pull the G1 voltage to low value during a sufficient time duration.
-120V
Case #1: Low Rx.Cx
Cx
A spot might appear during
the switch-off phase
Case #2: High Rx.Cx
No spot effect
R1
Rx
DDS
= 60 µA when V
-30V
G1
CC
<1.5V) in stand-by mode
STV9555
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