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How to power VBT on OLED?

tinhead

New member
I'm reffering to the CFAP2002A-Y-JCV.

Power via Resistor or Voltage-regulator?

Does the current-draw and intensity vary with the ammount of pixels on?
If so, should VBT be powered by a voltage-regulator (2.0-3.0V, ~30mA or more?), or will 5V via a resistor of 75 to 125Ohm(?) do the trick?

If the intensity varies, could I burn out a single pixel by applying 3v and something like 25mA?

Thanks in advance!
tinhead
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tinhead

New member
No reply it seems..

I have found some info on my own, the current does change in realtion to the ammount of lit pixels.
ie. a voltageregulator would probably be a good bet to get a nice and even output.

One question does however remain: If a resistor is used, could one burn single pixels as described above?
 

CF Tech

Administrator
Sorry for the delay in replying.

I need to run some tests myself to understand it better myself. I almost think that there was a regulator on the board . . . but I'm not sure.

I'll have to hook one up or contact the factory engineer to be sure.
 

tinhead

New member
No worries :)

I have found a display that seems similar to yours here (it's in german but look at page 3). They seem to use a 1kOhm resistor or a 5k+25kvariable from +5v to power Vbt.
Might it be something similar?

If you could clarify this more I'd be really glad! :)

Thanks
 

Pyrofer

New member
I used the PLED screen to replace an LCD and pretty much just soldered it onto the old LCD connector.

I used a 10k VR between 5v and GND (the same one that I used for contrast on my LCD) to run Vbt.

5v________________________
\
|/____ Vbt
/|
/
0v---------------------------------------

Is this going to burn out my display? I seem to get a good range of control on the brightness of the display and have it turned down quite a way from the brightest it can go.
 

CF Tech

Administrator
Well, these displays are meant to be "drop-in" LCD replacements, so I am not surprised that they worked fine that way.

As long as you do not wun the brightness too high (there is a brightness vs. lifetime tradeoff) then you should be fine with your circuit.
 
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