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Dear friends, i need your help

I bougth some time ago a LCD displaytech 64128C, Based on KS0108.
http://www.displaytech.com.hk/pdf/graphic/64128c%20series-v11.PDF

From RS stock N° 532-7029

But i've some doubt for pinout, specially with contrast control. That, because en datasheet appears VO and FGND. That diffiers form "VEE"

I has been searching for some information and i can think that my LCD don't have VEE (negative supply) to feed Vo.

So, How can i connect Vo and FGND to my wiring?

Datasheets sais Vo = VDD-19, so if i connect VDD to +5V, i need -14V, that's true?

Any information would be appreciated
Thanks a lot
(Sorry my english)

Seems that reasonably recent KS0108 based screen have a built in DC-DC for the backlight contrast. The cheapo one I have from SureElectronics sure has anyway.
Just feed 5V thru a pot (I use 2K2) and it might just work ...

Hello,

on some displays I used, the FGND is the Frame GND (the GND conected to the metallic frame that hold the crystal agains the PCB), so just connect it to GND.
For the VO, the datasheet uses to show a diagram were it is connected to a POT between Vcc and Vee (negative). For most applications the negative voltage is not needed, as it is required only for very low temperatures of operation (to guarantee contrast all over the temperature range). You can try to connect a POT between Vcc and GND, or directly connect VO to GND for maximum contrast. If it is too dim, then you will require the negative supply anyway, but it uses to be enough.

Hope this helps.
Cex.