• Theory:-

> BCD (Binary Coded Decimal) represents each decimal digit (0–9) using its 4-bit binary equivalent.

> Excess-3 code is a non-weighted code derived from BCD by adding 3 (0011) to each BCD digit.

> This code helps reduce errors and is often used in digital displays and arithmetic operations.

>The conversion rule is simple:
Excess-3 Code=BCD+0011

> For example:

      > Decimal 5 → BCD = 0101 → Add 0011 → Excess-3 = 1000

> Excess-3 code has no invalid combinations for decimal digits (0–9

    LOGIC  DIAGRAM:

   TRUTH TABLE:

• Boolean Expression:-

>  X3 = B3'

>  X2 = B2' B3' + B2 B3

> X1 = B1 B2' B3' + B1'B2 + B1'B3

> X0 = B0 + B1 B2 + B1 B3