MOSFET-Based RF Switch With Active Biasing

A biasing method for a stacked field-effect transistor (FET)-based radio-frequency (RF) switch is proposed. The advantage of the method over conventional passive resistive biasing is the ability to sustain a desirable operating point under the peak RF excitation conditions achieved by compensating the excessive leakage current of FETs in the stack. Operating point stabilization results in improved RF voltage-handling capabilities of the OFF-state switch. A single-pole double-throw (SPDT) hardware demonstrator implemented in a dedicated 130-nm bulk-CMOS RF switch technology shows an increase in breakdown voltage by 10% for a 35-V voltage-handling class switch device. The improvement is achieved at the expense of increased peak current consumption and no penalty in the RF performance of the switch.