Tcp Damage; Crystal(Ctrl B/D: X1) Damage - Daewoo DPP-42A1LASB Service Manual

3-5. TCP Damage

(1) In case of shorting or opening the IC output of TCP, it may
show one or several vertical lines.
Test Point: Enlarge the after measuring output TP of
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GND~TCP
Wave format: As shown output below figure.
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In case of normal wave output, when STB signal is
generated, maintain High output. And when STB signal
is generated again must be fall Low.
But when IC of TCP is poor, STB signal is not generated
Output falls with Low.
<When IC output of COF is poor>
(2) In case of being damage IC of TCP or power resistance, the
screen doesn't be shown or happens discharge partially.
Test Point: Enlarge the after measuring output TP of
O
GND~TCP
Wave format: Output wave doesn't come out
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<TCP Normal Output Wave >
Measurance position: Enlarge the after measuring output
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TP of TCP (Full White Pattern)

3-6. Crystal(CTRL B/D: X1) Damage

(1) When Crystal is damage, the screen doesn't be shown.
Test Point: Measuring 3pin of GND~Crystal(CTRL B/D:
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X1)
Wave format: Output wave doesn't come out
O
(2) In case of unusual launch of the Crystal, it may blink the
screen.
Wave format: As shown below figure
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<When Crystal is poor>
<Crystal Normal Output Wave >
Measurance position: Measuring output 3pin of
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Crystal(X1: 100MHz) on CTRL B/D (Full White Pattern)
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