Newhaven Display Forum

Newhaven Products => Character LCDs => Topic started by: 8510Leo on February 15, 2016, 06:42:23 PM

Title: NHD‐0216HZ‐FL‐YBW‐C adjusting contrast with manufacturer disabled pin
Post by: 8510Leo on February 15, 2016, 06:42:23 PM
Hello,

In this LCD manufacturer disabled pin 3 which is used in other versions of the basic modules for adjusting a contrast. Is there any way to adjust the contrast, as a text on the module is barely visible at current settings?

Thanks,
Leo
Title: Re: NHD‐0216HZ‐FL‐YBW‐C adjusting contrast with manufacturer disabled pin
Post by: 8510Leo on February 16, 2016, 05:59:56 PM
I found that the contrast can be significantly changed by modifying Supply voltage of the module (VDD). Actually, it was stated in the technical note as an (additional to VDD) parameter Vlcd - 4.4V.

Leo
Title: Re: NHD‐0216HZ‐FL‐YBW‐C adjusting contrast with manufacturer disabled pin
Post by: Saurabh_B on February 17, 2016, 11:15:44 AM
HI,

This display does have a temperature compensation circuit built in.
This circuit is tied to both the VDD, so modifying the input voltage will affect the contrast. The VLCD is VDD-V0, the V0 is supplied through the temperature compensation circuit.
At 25C this should produce approx. 0.6 V.

When used normally what voltage do you see across the VDD and VSS pins?
Title: Re: NHD‐0216HZ‐FL‐YBW‐C adjusting contrast with manufacturer disabled pin
Post by: 8510Leo on February 27, 2016, 09:13:09 AM
Thank you for the comments. At room temperature and VDD +5V module demonstrates a very good contrast. So, this is 4.4V Vlcd.

Best,
Leo