DAC Architeture

[TXRX]

Hi,

I have signal at Bandwidth of 100MHz, the sample rate is 200MHz.

What will be prefered ?

Option 1: ADC 8 bit.
Option 2: ADC 3 bit with Sample and Hold.

Thanks,

 

[barry]

How do we know what's "preferred"??? I dont have any requirements, do you?

 

[KlausST]

Hi,

I agree with Barry.

And according Nyquist the sampling rate needs to be HIGHER than 2 x signal frequency.

Klaus

 

[barry]

To expand on what Klaus said, sampling a 100MHz sine wave with 200MHz could conceivably give you an output of 0V DC. So then it doesn't matter WHICH solution you use.

 

[dick_freebird]

At exactly Nyquist you could do as well with a 1-bit
DAC (inverter / buffer).

At lower frequencies you say nothing about desired
accuracy.

A post-sampling could eliminate some spurs that
may come from not-ideally-aligned inputs causing
a non-monotonic transition from "code N" to
"code N+1" as elements of the DAC reswitch.

But you ask for DAC and then talk ADC mostly.
What's the real interest and some idea of real
requirements?

 

[TXRX]

Sorry, It is need to be ADC and not DAC.