*ABOUT*

This is a very simple number comparator circuit.

You input 2 numbers and it gives an output

whether **A > B** (both are 2-bit numbers)

(A should be strictly greater than B)

Note that A and B are both 2-bit **binary **numbers. Binary meaning that they are represented with only **1**s and **0**s.

Remark: Even if you don't know about binary numbers, I have got you covered :)

Simply refer to the table given in the circuit to work out the input yourself.

### How to use?

Change the first input number labelled as A1 A0 by toggling the input. Similarly change the second number. Observe the LED for each combination of 2 numbers.

*OUTPUT*

You will see an LED glowing if A > B. Otherwise, you won't see any output.

eg. If you input A1A0 as 11 and B1B0 as 10, the LED would glow.

### How I came up with the circuit?

Or rather you would ask, how can I design such a circuit myself? Well I will explain. So this is called a combinational circuit. You can design your circuit by first making a truth table with inputs as your two 2-bit numbers (4 inputs in total) and thinking about output for each set of inputs. So, you would have 4^{2} =**16 total inputs **in your truth table.

Next, after you have mapped your input and then your output for all those inputs, you would be solving a logical expression for output **Y **for a given set of 4 inputs **A**_{1}A_{0} B_{1}B0_{0.}

You can use any method to solve for Y. You can use a K-map based reduction or you can simply solve using basic logic identities.

Once you get an **expression (expression **means** **something like this say (for eg. this is not what you may get) Y= A1.B1'+B1'B0'+...**)**

, you would then realize the circuit using logic gates. Just as I have done.

#### What you can try to do afterwards

Increase the input to 3-bits , 4-bits and so on...