Digital Subtractors:

Another type of combinational arithmetic circuit is the binary subtractor, which provides an output that is the subtraction of two binary values.

A binary subtractor, as the name suggests, is a decision circuit that subtracts two binary integers from another, such as X - Y, and calculates the resulting difference between the two numbers.

When two binary numbers are added, a binary subtractor produces a DIFFERENCE, D by using the BORROW, B bit from the previous column, unlike a binary adder that produces a SUM and CARRY bit. The subtraction operation is clearly the inverse of the addition operation.

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