Winner Take all circuits are widely used in hardware implementation of pattern recognition systems based on Hamming Neural Network. WTA is a kind of competitive network which takes voltage or current as its input. The WTA function is to accept input signals from outer world, compare all the received inputs, largest intensity signal is accepted by WTA and assign a high digital value to corresponding cell storing largest intensity input and rest are assigned logic low value to the corresponding cell that stores smaller intensity input signals. Based on the type of input, WTA are classified into two types: current mode and voltage mode WTA. The circuit is simulated using 180nm CMOS Technology. These circuits are later used in hardware implementation of Hamming neural network(HNN) for number recognition.