Dark sub-pixels
(sometimes called off-pixels, stuck-off, or black
pixels) are characterized by the appearance of dark
pixels in white, red, green, or blue full-screen
picture.
Combined sub-pixel
defects are characterized by at least two sub-pixels
defects (bright or dim) being closer than 5 mm to
each other.
Temporal sub-pixels
(sometimes called blinking defects) exhibit
temporal variations not related to any steady-state
video input. Temporal sub-pixel defects may be
intermittent, exhibit a sudden change of state, or
be flickering.
Table 8 Defects table
Item
Bright dot (sub-
pixel) defect
Dark dot (sub-
pixel) defect
Total
1
Defect counts
Not allowed
2
Combined sub-
pixel defect
Not allowed
3
Temporal sub-
pixel defect
Not allowed
Note:
Blinking pixels are not allowed in normal operating temperatures and light conditions.
Introduction to display troubleshooting
The display module is a 640 X 480 VGA colour LCD known as 'Batura.' It connects to the main engine by a
multi-way ZIF connector. The locking lever mechanism on this connector must be carefully lifted up before
removing the LCD flexi.
The following references on the PWB help in the effective debugging and troubleshooting of the display.
Sr No
Reference
Description
1
X2450
Display connector
2
D1400
BCM2727B IC
The following test points on the PWB help in the effective debugging and troubleshooting.
Sr. No
Signal name
Measuring point
Description
1
VIO
L2473
1.8V supply to display
2
VAUX1
L2472
2.78V supply to display
RM-609
BB Troubleshooting and Manual Tuning Guide
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