MUC controlled brightness for OLED

[kieran]

Hi.
I am designing a project that will use the CFAP1602B-Y-ECS OLED display. I need to be able to control the brightness of the display using a micro-controller (AVR ATmaga32) and a digital potentiometer (AD5162). This pot has a maximum wiper current of 5mA, and from this forum I have seen that the display will draw up to nearly 50mA.
Does anyone have ideas for a circuit to interface the pot to the Vbt pin?

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[CF Tech]

It looks like the current into the Vbt pin is less than 1/4 mA for the data we took on 16x2 module:

 

[kieran]

Thanks, that is very useful.
In the "PLED is great, but what is the current draw?!? " thread there is a plot of the "Total Currents (Ivbt + Ivcc)" which reaches nearly 50mA, if Ivbt is no more than 0.25mA can I assume that the rest of the current is drawn from supply pin (Vdd in the data sheet). The data sheet states than the maximum current drawn by the Vdd pin (Idd) is 0.6mA, is this wrong?

 

[CF Tech]

Arrg. The data sheet is probably goofy. I'll contact the factory engineer and ask for an explanation / correction.