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DAC Architeture

TXRX

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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,
 

KlausST

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Hi,

I agree with Barry.

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

Klaus
 

barry

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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

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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?
 

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