Samsung PDP4298ED, Service Manual, Page: 45 / 102

Circuit Operation Description
5-26 Samsung Electronics
5-4-2(C) PRINCIPLES OF FET’S OPERATION AND HIGH VOLTAGE SWITCHING
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FET’s operation principles
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FET’s high voltage switching principles
(1) With no signal impressed on G1, FET1 gets
open-circuited, and with signal impressed on
G2, FET2 gets short-circuited, thereby causing
GND to be outputted to output terminals.
(2) With signal impressed on G1, FET1 gets short-
circuited, and with no signal impressed on G2,
FET2 gets open-circuited, thereby causing
180V to be outputted to output terminals.
(1) With signal impressed on the gate (Positive voltage),
FET gets short-circuited (a conducting wire of zero (0)
resistance); and
(2) With no signal impressed on the gate (GND), FET gets
open-circuited (a non-conducting wire of
∞
resistance).