Analysis and modeling on linearity for multi-throw TX/RX switches

Analytical analysis on linearity of multi-throw switches is given that serves as design guide. A switch multi-gate switch model is developed that includes all important mechanism associated with linearity, such as CV below pinchoff, leakage between gate to drain/source and drain to source. A highly linear nine-throw switch for GSM/WCDMA applications is used to validate the model that shows an IMD3 of -105 dBm at the control voltages starting as low as 2.8/0 V. This high linearity performance was achieved using good control on CV flatness and leakages in processing.