Today, I study the R-2R DAC, I find that I can not calculate the voltage by hand.
I draw a pic show below.
If S4 is high, it is easy to calculate that vout is 1/2 vref, but if S3 is high and the other is zero, how can calculate the vout by hand? I calculate it and vout is 1/4.
but if S2 is high, how to calculate? it is too difficult by hand.
it would need assumption to solve... because each value can be either 5V or 0V.... it involves solving in a cascaded way... i have tried before and got exact result...
I think u may apply the prinnciple of superposition i.e. assume one source is high and the others are low then sum the outputs to get the value of Vout