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Backlight on CFAF240320P-T


New member
I am alittle confused :confused: about the voltage requirements for the backlight on the CFAF240320P-T display. The specification states 3.2VDC, 20mA, and LED in parallel in Table 3.2 LED Backlight Characteristics. But, on our website and on page 16 of the specification states 12.8VDC, 15mA with the LEDs in series.

Any help on this question would be greatly appriciated. :)
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New member
Hi there, the LED's are 3.2V each with 20mA max per LED. When in series, the voltage is 3.2V x number of LED's. The current is then applicable at this voltage, hence the lower value.

You can drive the LED's from your 3.3V supply to the LCD but you will need a LED driver such as the NCP5005 from National to step this up to 12.8V or higher. (Thanks too CF Tech for help with this)

I have designed my circuit around the NCP5005 and it is easy to work with an parts are readily available. Unless you have 12V available, you will need to use this and create a PCB for it as the part is very small and only in SMD.

Good luck