Fast Fourier Transform (FFT) has an important role in many Digital Signal Processing (DSP) systems. E.g., in Orthogonal Frequency Multiplexing Division (OFMD) communication systems, FFT and inverse FFT are needed. The OFMD technique has become a widely adopted in several wireless communication standards. When operating in wireless environment the devices are usually battery powered and, therefore, an energy-efficient FFT implementation is needed. In CMOS circuits, power dissipation is proportional to the square of the supply voltage.