We verifid possibility of high sampling rate and lower power consumption current mode ADC that focused on the most high-speed operation for millimeter-wave broad-band wireless terminal such as wireless personal area network (WPAN). A 5 bit 1 giga-samples-per-second (GS/s) current mode pipeline ADC has been designed and fabricated in 90 nm Si complementary metal oxide semiconductor (CMOS) process. The fabricated ADC has no miscode and increases monotonically. In addition, differential non linearity (DNL) is less than 1.0 and integral non linearity (INL) is less than 1.25, power consumption is 52.8mW on 1 GS/s.