Wired CDMA interface with adaptivity for interconnect capacitances is designed to receive transmitted data even under a wide variety of connection topologies. The variable gain amplifier (VGA) is one of key circuit blocks to realize the adaptivity for interconnect capacitances. The system level numerical simulations derive the VGA specifications that the required VGA gain range is from 0.37 to 2.0, which can be realized easily using a multiple-differential-pair technique.