SR Flip flop are the basic element of the sequential circuit. Flip flop is a digital circuit capable of storing single bit of binary data. They can store either of the two [[wysiwyg_imageupload::]]stable state that is binary zero or one. If flip flop is set to one particular state it will store that until power is switched off or until you have changed the state. Means flip flop remember the state it was previously set and memorizes the date provided to it. Here we have designed the SR flip flop with the use of NOR gate. SR flip flop or SR latch is the most essential and widely used flip. It is also known as SET-RESET flip flop. SR flip flop has two inputs S and R. S is used to set the flip flop and R is used to reset the flip flop and two outputs Q and Q(NOT)  in this one is complement of another. When flip flop is storing 1 we can said that it is set and while reset it is storing 0. 

  NOR Gate is created by applying NOT operation to an OR gate. Hence, the outputs of this gate are opposite to that of OR gate when the inputs are kept same.[[wysiwyg_imageupload::]] Logic gate consists of three basic logic gates namely NOT, AND and OR. Each of them performs a different logic function. NOT gate is a logic element whose output stage is always the complement of the input stage means when you supply logic 1 we will logic 0 and vice versa. The operation of AND gate is such that output of gate is binary 1 if and only if all input are binary 1. If any of the input is binary 0 we will receive output as binary 0. OR gate is another basic logic gate like AND gate it as two input and one output.  

CD4001 is the most commonly used Complementary Metal Oxide Semiconductor (CMOS) chip.  It comes in a 14 pin Dual Inline Package (DIP). It has small [[wysiwyg_imageupload::]]notch on one side which is identified as pin 1.It consists of 4 independent NOR gate in a single chip. Each gate has 2 inputs and 1 output. Working voltage range of IC is from 5V to 15V. It can deliver approx.10mA at 12V but this can be reduced as power supply voltage reduces. IC consists of 14 pin where pin numbers 7 and 14 are connected to battery or DC power supply. Negative is connected to pin 7 and pin 14 is connected to power supply. As we know it has four gates we call it NI1, NI2, NI3, NI4. In first gate NI1 pin 1 and 2 are for inputs and pin 3 is for output.