PIC/STM32-Core Luminance-circuit

[Braintu]

Hi everybody.

I tried to understand the Luminance-circuit of the PIC/STM32-Core because I want to know if I can use a Display (2x16). The Datasheet-specification says that there should be about 3.3-3.7 V and 45 mA.

Can anybody give me a hint how to analyse this circuit?

Thanks

braintu