Product Specification

LM240WU8

Liquid Crystal Display

Table 2-2 . LED Bar ELECTRICAL CHARACTERISTICS

Parameter

Symbol

Condition

Values

Unit

Notes

Min.

Typ.

Max.

LED :

1,7

LED String Current

Is

-

110

120

mA

2,7

LED String Voltage

Vs

46.4

51.2

56.0

V

3,7

Power Consumption

-

22.5

24.6

Watt

4,6,7

LED Life Time

LED_LT

30,000

-

-

Hrs

5,7

LED driver design guide

1) The design of the LED driver must have specifications for the LED in LCD Assembly.

The performance of the LED in LCM, for example life time or brightness, is extremely influenced by

the characteristics of the LED driver.

So all the parameters of an LED driver should be carefully designed and output current should be

Constant current control.

Please control feedback current of each string individually to compensate the current variation

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Apr, 07, 2011

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Please control feedback current of each string individually to compensate the current variation

among the strings of LEDs.

When you design or order the LED driver, please make sure unwanted lighting caused by

the mismatch of the LED and the LED driver (no lighting, flicker, etc) never occurs.

When you confirm it, the LCD module should be operated in the same condition as installed in

your instrument.

2) LGD recommend that Dimming Control Signal ( PWM Signal) is synchronized with Frame Frequency

for Wavy Noise Free.

1. Specified values are for a single LED bar.

2. The specified current is input LED chip 100% duty current.

3. The specified voltage is input LED string and Bar voltage at typical 110 mA 100% duty current.

4. The specified power consumption is input LED bar power consumption at typical 110 mA 100% duty current.

5. The life is determined as the time at which luminance of the LED is 50% compared to that of initial

value at the typical LED current on condition of continuous operating at 25 ± 2°C.

6. The LED bar power consumption shown above does not include loss of external driver.

The used LED bar current is the LED typical current.

Min Power Consumption is calculated with PBar = Vs(Min.) x Is(Typ.) x Nstring

Max Power Consumption is calculated with PBar = Vbar(Max.) x Is(Typ) x Nstring

7. LED operating DC Forward Current must not exceed LED Max Ratings at 25

±2 °C