Design a VGA control board for an LCD.

I'm not entirely clear what you're after. Are you saying that you just have the glass and want the interface card, or do you have the whole monitor without a VGA input?

Digital View makes interface cards

however I'm not too sure of the current pricing, or availability in small quantities. I redesigned the model MAV-1280 LCD card for them in early 2000 to get it to pass CE, and I can tell you that there is nothing simple about it. You will also need the inverter board to operate the backlight.

If you know of a monitor which uses that glass, you could look for a broken one on eBay to get the driver boards.

Chris

not 100% sure of the question either, but here is a potential answer:

Don...

--
Don McKenzie
E-Mail Contact Page:               http://www.dontronics.com/e-mail.html

Micro,TTL,USB to 1.5" color LCD http://www.dontronics.com/micro-lcd.html
USB,RS232 or TTL to VGA Monitor http://www.dontronics.com/micro-vga.html
World\'s smallest USB 2 TTL Conv http://www.dontronics.com/micro-usb.html

I have a NEC NL128102AC31-02 LCD. This would describe what it is:

I think it's almost VGA ready, unless...

Thanks for your resp> Christ>

Actually, mine is the version 01 instead of 02 of the LCD, this link is better:

It now seems to boil down to how to generate the "dot clock" signal from the VGA signals .

Any comments ?

Thanks,

snipped-for-privacy@gmail.com wrote:

sure

and

the

Well the options are many ... a few bucks of some components of an LC tank oscillator with a quartz crystal will get you your dot clock. Any PC with an average VGA card can generate for you a dot clock signal. Zdnet once had a basic program for download that could do that so if you hunt for that you can play around with all the possibilities.

It would seem though you need more then a dot clock oscillator ... Your monitor specs indicates that it uses differential low voltage signals for video input ... The interfaces for such are usually expensive but Kontron produce(d) one of those starting at 72 dollars which is cheap. Try the following url

lemonjuice

Sorry for being confusing at the begining, but the monitor version 01 does use the analog RGB. The link for Kontron shows interesting products.

What if I like to use the monitor on a generic VGA device (tuner..) not sure the dot clock signal is easily found. Even on a PC VGA card, would it feasible to carry it (100 Mhz signal) along the cable ?

Thanks,

lem>

Looking at the attachment would seem to indicate that the monitor accepts TTL level RGB inputs. If that is the case then you wouldn't see anything because analogue RGB inputs are lower voltage levels then the TTL ones. However some thinking plus extra circuit components will somewhat clear the problem.

Normally what travels on your video cable is the output from your Random Access Memory Digital to Analog Converter on your video card which is normally a seperate chip though sometimes it is incorporated in your Video processor. The frequency given is always the "maximum" frequency which depends on seperate circuitry that generates the dot clock signal on the VGA adapter. Many modern video adapters though have different dot clock signal generators. The actual frequency will always be lower as it is a function of monitor settings like refresh rate etc. 100Mhz looks quite feasible. It is actually true that to maximise your visual experiance you have to match your monitors bandwidth to the dot clock frequency but then that is another subject.

lemonjuice

I'd venture that almost any video card you could purchase today would have an integrated ADC; outboard ADCs haven't been common (at least in "run of the mill" video cards) for many years now.

Dot clocks are often above 100MHz as well... a 1600x1200 60Hz display is

144MHz, and about the highest resolution monitors that still have analog inputs are probably 1920x1200 @ 75Hz = 172.8MHz.

---Joel

You don't seem to have noticed I was talking about Digital to Analog converter and not Analog to Digital converters.

BTW what is the deal with ADC ... most modern monitors use Analog input signals.

And the Op's monitor has an Analog input signal.

More like 1600*1200*60 =115.2Hz No deal though talking about a 1600x1200 resolution when the Op's monitor goes up only to 1280x1024

Still higher resolution? However this calculation doesn't take into account the blanking times of the horizontal and vertical scan which gets you a completely different dot clock frequency.

lemonjuice

[snip]

Analog Devices makes several chips that will generate dotclock from RGBHV. It's their AD988x series.

...jerry