Code Converters

A code converter circuit will convert coded information in one form to a different coding form.
One example of code conversion is to convert BCD to straight binary.
The weighting of BCD bits is not the same as straight binary. The weight of each bit within a BCD digit is 1, 2, 4, 8 respectively; but, each digit must be multiplied by its decimal positional value (1, 10, 100, 1000, etc.).
The 74184 IC will convert 1 ¹/₂ BCD digits to straight binary. (the LSB is the same in BCD and in binary).
The 74158 IC is used to convert 6 binary bits into a BCD code (again the LSB is feed around the chip).
Converters are also available that convert BCD input to a seven segment code output such as the 7447 IC.