NOTE:

*1. The display can not happen flicker or shutdown.

*2. Limited lamp maximum current by DAC_BRIC signal:

DAC_BRIG signal comes from system with internal resistance of 3K .

When add 1V DAC, the 100% Lamp current will decrease 0.5mA.

Lamp limited current

DAC_BRIG

INV_PWM

 

 

 

Max.

0V

100%

Min.

3.3V

100%

 

 

 

*3. Inverter operating frequency should be within specification (50~70kHz) at max. and min. brightness load.

*4. INV_PWM enable implies INV_PWM signal is High level (On duty cycle is 100%). It is a square wave of 150Hz to adjust backlight brightness that is a function of PWM duty cycle. Backlight brightness is maximum value under INV_PWM at 100% and brightness is minimum under INV_PWM at 40%.

*5.The system interface signals belong to 3.3V.

*6. Please make sure open lamp output voltage should be within starting voltage specification.

*7. Inverter should pass human body safety test.

*8. Inverter should be no smoking by any component open/short test.

*9. Transformer voltage stress should not be over 85% under any condition. (turn on overshoot transient and line transient.)

*10. Inverter should without acoustic at 10cm distance..

Electrical specification

No

Symbol

Min.

Typ.

Max.

Unit

Comment

.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

V oper*

--

785

--

Vrms

Lamp operating voltage

 

 

 

 

 

 

 

 

IL

6.2

6.5

6.8

mArms

DAC_BRIG: 0 V, PWM:

 

 

 

 

 

 

100%

1

 

 

 

 

 

 

IL

3.3

3.6

3.9

mArms

DAC_BRIG: 0 V,

 

 

 

 

 

 

PWM:40%

 

 

 

 

 

 

 

 

IL

5.7

6.0

6.3

mArms

DAC_BRIG: 0.5V,

 

 

 

 

 

 

PWM:100%

 

 

 

 

 

 

 

 

IL

3

3.3

3.6

mArms

DAC_BRIG: 0.5V,

 

 

 

 

 

 

PWM:40%

 

 

 

 

 

 

 

 

f

50

60

70

kHz

 

 

 

 

 

 

 

 

 

η

76%

--

--

--

 

 

 

 

 

 

 

 

Thermal

All components on inverter board should follow below rules:

1.Component using conditions (component stress) must be within component specification including voltage rating, current rating, temperature etc.

2.Component temperature should follow below:

∆T <=40° C, at 25° C and without airflow.

Component temperature can’t the Bezel deformed of system.

Chapter 1

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Acer 1800 manual Lamp limited current, Electrical specification, Thermal