
5. Trouble shooting
5.13 Qwerty Key trouble
Key Check Points
-Dome switch contacts
-Key coder IC soldering
QWERTY KEY
2V62_VIO
I2CSDA |
TP4
C400
0.1uF
2V62_VIOR400
120K
KEY_ | 2V62_VIO | |||
0 |
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C401 0.1uF
(1%)
R401 | R402 | 4.7K |
KEY_COL7 KEY_COL6 KEY_COL5
KEY_INT KEY_I2C_SCL
2V62_VIO
| 27p | 27p | 27p |
| C402 | C403 | C404 |
R405 | 470 |
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R407 | 470 |
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R409 | 470 |
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| R411 |
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| TP2 |
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| R415 |
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| 4.7K |
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| 1 |
| PGND GND2 | RESETB | XI | XO | CLK SEL | VDD | P10 | |||||||
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| 2 | TEST |
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| 4 |
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| 5 | P56 |
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| P17 |
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| 0 | 7 |
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| P15 | GND1 | P54 | P53 | P52 | P51 | P50 | P47 | |||||||
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| C420 | 27p |
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| C421 | 27p |
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| C422 | 27p |
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| C423 | 27p |
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| C424 | 27p |
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| 470 |
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| R416 |
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| R420 |
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P40 | 21 |
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| R403 | 470 | KEY_ROW0 |
20 |
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| R404 | 470 | ||
P41 | 19 |
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| R406 | 470 | KEY_ROW1 |
P42 | 18 |
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| R408 | 470 | KEY_ROW2 |
P43 | 17 |
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| R410 | 470 | KEY_ROW3 |
P44 | 16 |
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| R412 | 470 | KEY_ROW4 |
P45 | 15 |
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| R414 | 470 | KEY_ROW5 |
P46 |
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| KEY_ROW6 |
| C413 | C414 | C415 | C416 | C417 | C418 | C419 |
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| 27p | 27p | 27p | 27p | 27p | 27p | 27p |
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KEY_COL4 KEY_COL3 KEY_COL2 KEY_COL1 KEY_COL0
LGE Internal Use Only | - 90 - | Copyright © 2008 LG Electronics. Inc. All right reserved. |
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| Only for training and service purposes |