Newhaven Display Forum

Newhaven Products => Graphic LCDs => Topic started by: sergef on May 18, 2016, 06:04:38 AM

Title: NHD-24064WG-AYYH-V Backlight current
Post by: sergef on May 18, 2016, 06:04:38 AM
I've been looking at the datasheet of the NHD-24064WG-AYYH-V display and the backlight current (660mA) seems to be very high compared with other similar displays (about 100mA).

I want to use a voltage regulator to supply 4.2V but I can't find one who can handle 660mA that needs the display.

It's correct the data of 660mA shown at the NHD-24064WG-AYYH-V datasheet?

If yes, It's possible to connect the backlight display directly to a 5V Power supply?

Sorry for my poor english. I hope you can understand my doubt.

Thanks in advance for your help.
Title: Re: NHD-24064WG-AYYH-V Backlight current
Post by: Saurabh_B on May 18, 2016, 08:33:53 AM
Hi,

If you were to use a current limiting resistor in series with the backlight pins you can apply 5V directly to the backlight.
I would recommend using a ~1.2Ω resistor for this.
Title: Re: NHD-24064WG-AYYH-V Backlight current
Post by: sergef on May 19, 2016, 05:46:42 AM
I guess you want to say 1K2 ohm resistor (brown - red - red - gold/silver)

I'll try it if you confirm me that issue.

Thank you very much for your answer.
Title: Re: NHD-24064WG-AYYH-V Backlight current
Post by: Saurabh_B on May 19, 2016, 08:08:22 AM
No, you would want to use a 1.2Ω resistor. A 1.2KΩ resistor would result in a very dim backlight.
For a current limiting resistor you would want to do the following = (Vin - VLED)/(ILED)
(5-4.2)V
0.660 A

Which would leave you with ~1.21Ω

 ;)
Title: Re: NHD-24064WG-AYYH-V Backlight current
Post by: sergef on May 19, 2016, 12:44:08 PM
OMG!!! Basic Ohm's Law  ;D ;D ;D

How I didn't think it before? I feel like a fool  :-[

Thank you very very much  ;)