The USB switch is a bidirectional device that selects one of several input USB signals and forwards the selected input into a single line or vice versa. Pericom’s USB switch uses the NMOS gate technology with charge pump on the gate which enables it to increase the voltage at the gate to avoid output voltage clamp caused by the threshold. The advantages of the charge pump are: Wider Vcc range, Rail to rail output voltage without clamp, and Low Coff and Con.