Flash ADC without clock-based comparator

[eegchen]

comparator without clock

hi,

I am designing a very high speed Flash ADC.
I use CML circuit
And if my input frequency is 2 GHz. And i use several open-loop amp to amplify the error signal to rail-rail(CML swing).

obviously, this will cause power and large delay.

But if this work, how can i determine the sample rate, because there is no clock used in my Flash ADC design.

best WIshes
Gang Chen