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Which ADC is the fastest ADC? Flash ADC or Pipeline ADC?

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ywyw

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fastest adc

Hi Everybody:

Which ADC is the fastest ADC? Flash ADC or Pipeline ADC?

In my knowledge, the speed of ADC depends on its Conversion Rate or Sample Rate. This means if two type of ADC have same Conversion Rate or Sample Rate, then they have same speed, I mean they spend same time to finish one time A/D conversion. Correct?

I read ADC datasheet or article, they always talk about the speed of flash ADC is faster then Pipeline ADC but without comparing condition. They still talk about the speed of semi-flash ADC is half speed of flash ADC without comparing condition.

I got confused on this question:

(1)When people talk about the speed of flash ADC is faster then Pipeline ADC, what is their comparing condition?
(2)If a Flash ADC and a Pipeline ADC have same Conversion Rate, do they have same speed? If the answer is yes, then who want to spend more money and power to bay and use flash ADC with lower resolution? If the answer is no, which answer is correct?

Thanks in advance.

:?::cry:
 

mince

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fastest adc

A pipeline ADC generally several flash ADCs in series. Because of this you have a latency due to each flash. Plus you have to have opamps in a pipeline ADC and compensating the opamps limits the speed of the ADC. A flash ADC will be the fastest ADC you can have, but for it to have the same resolution as a 10-12 bit pipeline, it will consume a lot more area, input capacitance, and possibly more power. But the benefit is that the output data will be available usually 1/2-1 clock cycle later instead of several clock cycles later in a pipeline.
 

sayed_askari

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adc fastest conversion time

A Flash ADC is the fastest ADC in terms of speed but it has added disadvantage that we have to compromise on power vs resolution. Pipelined ADC comes second in terms of power.
 

dick_freebird

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At the same conversion rate, flash has less latency. Pipeline
has N clocks from original sample to output word. At a given power
allowed, and bit width, the pipeline will probably offer a higher
sample rate. But raw sample-to-output speed, the flash will
still win.

Question is, which aspect means "fastest" to you?
 

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