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Hi all !

These last couple of days i fidled around with a Seiko G191C display and a external MPI SED 1330 controller.

After many posts and trying different things i finally got it to display something.

However, i cannot get the EL Backlight to work.

Here is the Datasheet of the display:

link deleted

The wireing schematics i used can be found here :

link deleted


I am useing the Inverter mentioned in the Datasheet. the SKI-050-05H

When i take my multimeter to the display and set it to AC i mesure a current there of 140 VAC at the EL lead Terminals (see page 20 of the datasheet)

And the inverter is getting really really hot. I siwtched it out already once thinking it was broken but the 2nd one is doing the same thing, getting hot and no EL lightening up.

Ideas are much apreciated.

Thanks in advance.

Regards

tec

In my experience, EL and fluorescent inverters get hot when they are not driving a load, or are shorted.

Check the connections to/on the EL panel - check for a short with a resistance range on a multimeter. You could also check if there is any current drawn when it's powered - put the meter on a 100mA range first if it's not autoranging.

FoxyRick.

Hi Fox

Thank you for your reply.

I cannot find a short circuit anyway. however it seems you are right that there is no load on the Inverter, at least i am unable to measure anything.

How could that be ? As far as i am aware a EL backlight only has 2 connection, one beeing gnd the other one being power. And i have them both connected. Pin 13 and 14. I even switched them around once thinking it was printed wrong in the datasheet but to no avail.

but i got a question, on the backside of the LCD are 2 connectors for the EL backlight as well. In the datasheet they are called "EL lead terminal". Beeing not that great in the english language i cant translate into anything i understand. I measure a currency there when i hold the multimeter to it. They hurt too if you touch them.. .tried that.

I have them not connected at the moment, do i have to do that somehow ?

Best regards
tec

P.S: In case worst comes to worst and i have to put in a new EL foil can i do that the same way as the tutorials on the net show it for text displays or is it different for graphic lcds ?

Have you tried checking whether the tracks to the EL sheet are OK?
If it hurts when you touch them the inverter's OK
To replace the EL panel is the same as for text displays.

Hi Klaus,

Wiring the inverter to pins 13 and 14 is correct.

I think the EL panel should be connected to the "EL Lead Terminals". Check this.

Can you connect directly to the EL panel contacts? If you can, try connecting the inverter directly to it.

FoxyRick.

Hi guys

Ok today i finaly found the solution why it wasnt working...

*drums*

... there was no EL backlight in the display at all. Aparently this was a version of the display that just had the "possibility" to have an EL backlight added.

Well did that today. Was quite a pain lol but challenging. Unfortunatly on the lower corner is now a litte dark spot. dont know if htat is a finger print on the polarizer or a pressure point from the el foil.

I am unsure anyway if i did it correct by placing the EL foil directly against the poralizer, where i removed the old reflective stuff.

But at least its working now and for my 1st display i am quite happy with it. The only drop of sorrow is that tinly black area ...

and..

wished i had taken a bigger display lol. 192 x 128 is smaler then i thought.

Oh well.. always material for another project. heheh


Thanks once again you two

best regards

tec