Adder Subtractor Circuit. Although adders can be constructed for many number. When m 1 the circuit is a subtractor and when m 0 the circuit becomes adder.
The ex or gate consists of two inputs to which one is connected to the b and other to input m. In digital circuits an adder subtractor is a circuit that is capable of adding or subtracting numbers in particular binary. This is the circuit of an inverting amplifier and its output voltage is v 1 r r 2 v 1 2 v 1 similarly the output voltage v 02 due to v 2 alone is v 02 v 2 now the output voltage v 03 due to the input voltage signal v 3 alone applied at the input terminal can.
It is a combinational logic circuit.
Then full adders add the b with a with carry input zero and hence an addition operation is performed. In many computers and other kinds of processors adders are used in the arithmetic logic units or alu they are also used in other parts of the processor where they are used to calculate addresses table indices increment and decrement operators and similar operations. It is also possible to construct a circuit that performs both addition and subtraction at the same time. Below is a circuit that does adding or subtracting depending on a control signal.
