Low-voltage and low-power circuit structures are substantive for almost all mobile electronic gadgets which generally have mixed mode circuit structures embedded with analog sub-sections. Using the reconfigurable logic of multi-input floating gate MOSFETs, 4-bit full adder has been designed for 1.1V operation. Multi-Input Floating Gate (MIFG) transistors have been anticipating in realizing the increased functionality on a chip. A multi-input floating gate MOS transistor accepts multiple inputs signals, calculates the weighted sum of all input signals and then controls the ON and OFF states of the transistor. This enhances the transistor function to more than just switching.