hi i'm looking for an adc ic that 8 bit digital output whenever there is an analog input , without using a clock or strobe pins and no sampling .that means analog input (continuous) - >digital output instantaneously
can u help me with this matter

 

There needs to be some signal to hold the value for reading, as not all inputs have the same capture time. If the value changed while reading, the answer would be meaningless.

What is the application? There are already DACs that do 1 GS/s and higher, which is effectively "continuous" for any signal under 1Mhz.