Tcp Damage - HP PL4260N Service Manual

3-3. SCAN IC(Y DRV B/D : IC1~6,
IC101~106) Damage
(1) In case of SCAN IC poor, one horizontal line may open at
screen.
Test Point: ICT measurance of GND~Y DRV B/D output
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Wave format : As shown fig. 4
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<Fig. 3 When SCAN IC is poor>
(2) Screen may not shown when SCAN IC is damaged by
SCAN IC poor, external electricity or spark.
Test Point : ICT measurance of GND~Y DRV B/D output
O
Wave format : Output wave format isn't output (You can
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see the damage for Y DRV B/D Top or Bottom's SCAN
IC)
) In case of defects in Ass y, connecting cable between Y
DRV B/D(Top, Bottom) and Ysus, pictures will not appear.
Test Point : ICT measurance of GND~Y DRV B/D output
O
Wave format : As shown fig. 5
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<Fig. 5 In case of defective connection cable between
Y DRV B/D(Top, Bottom).>
(4) In case of shorting the SCAN IC output by a dust, foreign
substance, it may overlap two horizontal lines on screen.
Test Point : ICT measurance of GND~Y DRV B/D output
O
Wave format : As shown fig. 6
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Measurance position : SCAN section enlarge the after
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<Fig. 6 When SCAN IC output is short>
<SCAN IC Normal Output Wave >
measuring output ICT of Y DRV B/D.
(Full White Pattern)

3-4. 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 fig. 7
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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.