I am thinking of using a chip that gives out 4-6V on 7-segment output pins but the LCD only wants 3-5V input, so I need to convert somehow.
The display is a TN type, drawing virtually no current. The LCD data specification is tiny and poor and does not actually mention current consumption, but a similar device's spec mention max 2 µA/cm2, and the screen is 4 cm2. Since that is for the whole device, it is approximately 0.3µA per pin (8µA / (4*7)). (Are my assumptions flawed here?)
The solution have to be cheap since it should be applied to 25 individual pins, and also preferably also not take up a lot of space. One obvious, simple solution is to use a resistor voltage divider (10k + 47k would transform to 3.3-4.9V).
Do I have any other option?
My first thought was to put a diode (or two) in series, but that will not work because the voltage drop over the diode will not be that great for so low currents, right?
Since the LCD will draw so little current, would there be any problem using 100k + 470k instead of 10k + 47k?
Or can I just skip doing anything and feed the signals directly to the LCD, hoping it will be ok?