Author Topic: Driving the backlight LED for NHD-C12864WC-FSW-FBW-3V3  (Read 2673 times)

davepfz

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Driving the backlight LED for NHD-C12864WC-FSW-FBW-3V3
« on: September 30, 2015, 12:47:59 PM »
The LED voltage for the NHD-C12864WC-FSW-FBW-3V3 is specified as 3.0V at a current of 36mA. Does this mean that there is an internal current limiting resistor? None is shown in the drawing.

Although I don't expect to go there, what is the maximum current for the LEDs? (I plan to use a dimming circuit that will allow the user to adjust the backlight.)

Thanks

Michael_L

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Re: Driving the backlight LED for NHD-C12864WC-FSW-FBW-3V3
« Reply #1 on: October 01, 2015, 08:37:36 AM »
This display does not have a current limiting resistor, one should be used when powering the backlight.
The maximum current for the backlight on this display is 50mA.

raspdroid

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Re: Driving the backlight LED for NHD-C12864WC-FSW-FBW-3V3
« Reply #2 on: January 24, 2016, 07:16:44 AM »
Hello,

I am using this model for my project  with 3V3 voltage with one TPS61201, http://www.newhavendisplay.com/specs/NHD-C12832A1Z-FSR-FBW-3V3.pdf

It suffices with one resistor or is it better to use a 3.0V LDO?

TPS7703DBVR
http://www.ti.com/lit/ds/symlink/tps770.pdf

Regards

Paul_B

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Re: Driving the backlight LED for NHD-C12864WC-FSW-FBW-3V3
« Reply #3 on: January 25, 2016, 08:33:11 AM »
Morning,

It is typically preferred to supply the displays Typ. Voltage when ever possible, however in your case supplying 3.3V is perfectly acceptable  ;)

raspdroid

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Re: Driving the backlight LED for NHD-C12864WC-FSW-FBW-3V3
« Reply #4 on: January 25, 2016, 12:27:38 PM »
Thanks Paul,

Then I'll used 3V3 for supply and backlight.

Best regards
--Javier

 

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