Newhaven Display Forum

Newhaven Products => Graphic LCDs => Topic started by: Shaun_Caraway on May 19, 2014, 08:22:18 AM

Title: Contrast supply for NHD‐24064WG‐ATFH‐VZ#
Post by: Shaun_Caraway on May 19, 2014, 08:22:18 AM
Hello

I am using the NHD‐24064WG‐ATFH‐VZ#. I have never used a graphics LCD before and am curious about the VEE voltage supply for this particular LCD contrast supply. According to the diagram in the data sheet on page 4 it would appear that the contrast voltage supply (VO) is created by using a voltage divider or some sort of potentiometer to allow adjustments hooked up between VEE (Pin #9 ) and VO (Pin #4) .

(http://i.imgur.com/YY83QA5.png)

I see according to the table on page 4 of the data sheet that VEE is an output voltage and VO is labeled as supply voltage.

(http://i.imgur.com/CIjMPOT.png)

My question is do I need to supply VEE in addition to the VDD and the  LED +/- or is VEE supplied by the LCD module itself?

Thank you.
Title: Re: Contrast supply for NHD‐24064WG‐ATFH‐VZ#
Post by: Michael_L on May 19, 2014, 09:17:00 AM
VEE is supplied by the LCD module.  That pin outputs a voltage of -10V.  This negative voltage is used in conjunction with a potentiometer (connected between VEE and Ground, with the adjustable pin connected to V0) in order to provide approximately -7V for contrast (adjustable).
Title: Re: Contrast supply for NHD‐24064WG‐ATFH‐VZ#
Post by: Shaun_Caraway on May 19, 2014, 10:01:31 AM
Thank you for the quick response you have clarified my question nicely.