#### tony_wu_ad

##### Member level 3

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.

Pls help me , thank