This paper deals with the design and implementation of an 8-bit 2-Gsample/s folding-interpolating analog-to-digital converter (ADC) using a SiGe technology with a unity gain cutoff frequency f/sub T/ of 47 GHz. The high-speed high-resolution ADC has applications in direct IF sampling receivers for wideband communication systems. The converter occupies an area of 3.5 mm/spl times/3.5 mm including pads and exhibits an effective resolution bandwidth of 700 MHz at a sampling rate of 2 Gsample/s. The maximum DNL and INL are 0.5 and 1 LSB, respectively. The ADC dissipates 3.5W (including output buffers) from a 3.3-V power supply.