Analog to digital converter

[harrisonic]

hello everyone!!
i just wanna know what is the purpose of the gates(and,or,inverter) in this circuit?it is for bits?

Im just new..

thanks for the help..


also the gates are:

AND 74ls08
OR 74ls32
INVERTER 74ls04

 

[ronsimpson]

analog in out of comp. out of logic
0v to 0.75v 0,0,0 00
0.75v to1.5v 1,00 01
1.5v to 2.25v 1,1,0 10
2.25v to 1,1,1 11