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PW181 is also the main CPU. Its program is stored in the externally connected flash N601. The
software upgrading of RS-232 is actually the upgrading of the stored memory in N601 by PW181. The
interface of menu is also produced by PW181. PW181 can automatically produce self check signal for
trouble shooting.
2.3.3 Block diagram of PW181 is shown below:
The above is a short account of the signal flow process of the TV series. Please note HS (Horizontal
Synchronous), VS (Vertical Synchronous) and CLK (Clock), PEN (Enable) between individual stages are
invariably the basic reference for the mode identification of lower level chip. Make sure that they are in
normal working condition.
PW181 controls the standby of the complete TV set.
PORTB3 of PW181 is used to control the operation of the power supply board. When it is POWER_ON ,
the TV set is switched on with low electric level and is in standby with high electric level. When it's in
standby the remaining power supply is only 5VSTBY.
The voltage VS required by the operation of screen is also controlled by VS_ON output from logic
board. It is in operation when the electric level is high. Only when the logic board receives correct signal
(clock, synchronous, enable etc.) can VS_ON be correctly output. The operation of PDP screen has very
high demand for the time sequence of power supply. If the time sequence is wrong it might make the
screen unable to work normally.
The POWER-ON signal output from
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