Hi! acer aspire 7750 display is ok on external monitor, but dim on led lcd.
Main Voltages measured on JLVDS1 connector pins : +INVPWR_B+ : 21V Local_Dim_R : 0.8 to 1.1V INVTPWM : 3.6V +3VS : ok +LCDVDD : 3.6v +5VS : ok But BKOFF# : 0V ???
I guess that BKOFF# should be around 3v to enable backlight. Isn't true ? BKOFF# issued from EC kb930QF to JLVDS1 pin6 is supplied with 3VS through R342 (10k) and grounded through R15 (10k) // C6. BKOFF# resistance to ground measured about 4 ohms ?? Though I desoldered C6, resistance remained the same.
Does I have to replace the EC to get BKOFF# high and led backlight enabled? Please advise further. Thank you
vdklv
Заголовок сообщения: Re: acer aspire 7750 (LA-6911P rev:1.0) dim display on lcd
Добавлено: 10 апр 2014, 14:28
Я тут случайно
Зарегистрирован: 31 мар 2014, 09:07 Наличности на руках: 2.00 Сообщения: 19 Откуда: Komi
measured BKOFF# without LVDS cable? powered on/off?
mohkam3000
[ТС]
Заголовок сообщения: Re: acer aspire 7750 (LA-6911P rev:1.0) dim display on lcd
Wish to correct "Does I have to replace the EC to Get High and BKOFF # LED backlight enabled?" Does I have to replace the EC to Get BKOFF# High and LED backlight enabled?
vdklv
Заголовок сообщения: Re: acer aspire 7750 (LA-6911P rev:1.0) dim display on lcd
Добавлено: 10 апр 2014, 16:32
Я тут случайно
Зарегистрирован: 31 мар 2014, 09:07 Наличности на руках: 2.00 Сообщения: 19 Откуда: Komi
My question refers to check the LCD cable, because you have not written about resistance to ground measured 4 ohms with cable or not. And about your question:yes
mohkam3000
[ТС]
Заголовок сообщения: Re: acer aspire 7750 (LA-6911P rev:1.0) dim display on lcd
My question refers to check the LCD cable, because you have not written about resistance to ground measured 4 ohms with cable or not. And about your question:yes
hi BKOFF# resistance to ground is 4 ohms without cable. cable continuity checked ok.
mohkam3000
[ТС]
Заголовок сообщения: Re: acer aspire 7750 (LA-6911P rev:1.0) dim display on lcd [РЕШЕНО]
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