The optical signal processing is one of the application of the half subtractor circuit. Binary numbers is another application.
An adder-subtractor is a circuit capable of subtracting or adding binary numbers. The application of a 4-bit adder and subtractor is for use as part of the core of an ALU, or arithmetic logic unit.
A half-subtractor lets you borrow out, but not borrow in. A full subtractor is made by combining two half-subtractor and adding an OR-gate. (lets you both BOR_in as well)
Advantage:1:To overcome half subtractor, full subtractor comes into play
The half adder is an example of a simple, functional digital circuit built from two logic gates. A half adder adds two one-bit binary numbers A and B. It has two outputs, S and C (the value theoretically carried on to the next addition); the final sum is 2C + S.
-Half subtractor is used to reduce the force of audio or radio signals. -It can be used in amplifiers to reduce the sound distortion. -Half subtractor is used in ALU of processor. -It can be used to increase and decrease operators and also calculates the addresses.
To make a full subtractor, you need an XOR and a NAND gate.
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Subtractor :In Electronics Subtractor is a Combinatorial circuit which is used to Subtract two Binary Numbers, x & y.Half Subtractor :Half Subtractor is a circuit which is used to Subtract the two bit Binary Numbers.Full Subtractor :Full Subtractor is a circuit which is used to Subtract the Two Bit Binary Numbers and a 1 borrowed from Last Lower significant stage.Hope this answer will help you.....Remember In your Prayers.
A subtractor can be designed using the same aproach as that of an adder ,subtractor are usually implemented within a binary adder for only a small cost when using the standard two's complement notation,by providing an addition/subtraction sector to the carry in and invert the second operand. A subtractor using of diffrencate bits.
simply by complementing x input before applying to and gate for generating carry
design a one bit slice of the adder subtractor and iterate it through all 12 bits.