LB121S03
Liquid Crystal Display
Product Specification
5. The output of the inverter must have symmetrical(negative and positive) voltage waveform and
symmetrical current waveform.(Unsymmetrical ratio is less than 10%) Please do not use the inverter
which has unsymmetrical voltage and unsymmetrical current and spike wave.
Lamp frequency may produce interference with horizontal synchronous frequency and as a result this
may cause beat on the display. Therefore lamp frequency shall be as away possible from the horizontal
synchronous frequency and from its harmonics in order to prevent interference.
6. Let’s define the brightness of the lamp after being lighted for 5 minutes as 100%.
TS is the time required for the brightness of the center of the lamp to be not less than 95%.
7. The lamp power consumption shown above does not include loss of external inverter.
The used lamp current is the lamp typical current. (2 Lamp)
8. The life time is determined as the time at which brightness of the lamp is 50% compared to that of initial
value at the typical lamp current on condition of continuous operating at 25 ± 2°C.
* Requirements for a system inverter design, which is intended to have a better display performance, a
better power efficiency and a more reliable lamp, are following. It shall help increase the lamp lifetime and
reduce leakage current.
a. The asymmetry rate of the inverter waveform should be less than 10%.
b. The distortion rate of the waveform should be within Ö2 ± 10%.
* Inverter output waveform had better be more similar to ideal sine wave.
* Asymmetry rate:
I p
| I p – I –p | / Irms * 100%
* Distortion rate
I -p
I p (or I –p) / Irms
* Do not attach a conducting tape to lamp connecting wire.
If the lamp wire attach to a conducting tape, TFT-LCD Module has a low luminance and the inverter
has abnormal action. Because leakage current is occurred between lamp wire and conducting tape.
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Ver. 0.0
Feb. 27, 2006
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