LM170E01
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 as 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%.
The used lamp current is the lamp typical current.
7. The lamp power consumption shown above does not include loss of external inverter under 25
The used lamp current is the lamp typical current.
.
8. The life time is determined as the time at which brightness of lamp is 50% compared to that of initial
value at the typical lamp current on condition of continuous operating at 25
2
.
9. Requirements for a system inverter design, which is intended to have a better display performance,
a better power efficiency and a more reliable lamp.
It shall help increase the lamp lifetime and reduce its leakage current.
a. The unbalance rate of the inverter waveform should be 10% below;
b. The distortion rate of the waveform should be within 2 10%;
c. The ideal sine wave form shall be symmetric in positive and negative polarities.
* Asymmetry rate = | I p – I –p | / Irms * 100%
I
p
* Distortion rate = I p (or I –p) / Irms
I
-p
10. Inverter open voltage must be more than lamp starting voltage.
11. The inverter which is combined with this LCM, is highly recommended to connect coupling(ballast)
condenser at the high voltage output side. When you use the inverter which has not coupling(ballast)
condenser, it may cause abnormal lamp lighting because of biased mercury as time goes.
[ Figure 3 ] Mosaic pattern for power consumption measurement
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Ver 1.0
Mar. 28, 2005
LG [ LG SEMICON CO.,LTD. ]
