How Do You Calculate Resistor Values in a Digital to Analog Converter?

[uhdam]

Hello Everyone,

In Digital to Analog conversion circuit we use the weighted resistors(i.e R,2R,3R,4R) and one feedback resistor(i.e Rf). Here my question is that how to calculate the those resistor values? If you know any formulas please provide me...

 

[berkeman]

Hello Everyone,

In Digital to Analog conversion circuit we use the weighted resistors(i.e R,2R,3R,4R) and one feedback resistor(i.e Rf). Here my question is that how to calculate the those resistor values? If you know any formulas please provide me...

You don't want to use too large of a base resistance value, or you will limit your maximum output frequency too much (because of the stray capacitance in your DAC output layout).

You don't want to use too small of a base resistance, because that will take too much drive power.

The base resistance value that you choose should be just a bit smaller than what it takes to start limiting your output bandwidth lower than you want.