Completing an A/D converter.

[chelleteng]

Hi,

I am given a 2 bit digital output and I have to implement an ADC and maximize the number of bits/resolution through an analog circuit.. I've been reading up on ADCs and the Delta-Sigma converter seems the most relatable one in order to solve this problem because of its DAC feedback. Other than that, I am not too sure on how to use the comparator, integrator or flip-flop to do this. Am I heading in the right direction?

Thank you..

 

[crutschow]

If you have a digital output I don't understand where the ADC comes in? Do you mean you need a 2-bit DAC? What exactly are the inputs and outputs that you want?

 

[Monady]

Hi,

I am given a 2 bit digital output and I have to implement an ADC and maximize the number of bits/resolution through an analog circuit.. I've been reading up on ADCs and the Delta-Sigma converter seems the most relatable one in order to solve this problem because of its DAC feedback. Other than that, I am not too sure on how to use the comparator, integrator or flip-flop to do this. Am I heading in the right direction?

Thank you..

If I didn't get you in a wrong way, you mean 2-bit ADC is going to be the internal converter in another circuit. In this case, you can use delta sigma ADC and get much more resolution from that 2-bit ADC, due to the noise shaping and oversampling. Probably you need to take a look at a book written by Schreier "Understanding delta sigma data converters"

 

[one25]

I suppose that you can increase the resolution using PWM on lower bit. You can use an active filter after this and then a summing circuit.