Switching Time Acceleration for High-Voltage CMOS RF Switch

Abstract

A high-voltage MOSFET-based RF switch with improved switching time is presented in this paper. The improvement is achieved by adding an auxiliary circuitry distributed along the stack which substantially speeds up the charging and discharging of gate oxide of the transistors. The auxiliary network is enabled by a delay-based control circuit defining acceleration time-window for switching transient. An RF switch comprising the proposed solution has been implemented in a dedicated 65 nm CMOS switch technology. The measured hardware demonstrates the improvement in switching time from $19.2\ \mu s$ to $1.6\ \mu s$ in OFF-to-ON direction and from $0.6\ \mu s$ to $0.2\ \mu s$; in ON-to-OFF direction compared to the state-of-art implementation. The improvement is achieved at no penalty in key RF characteristics of the device. Particularly, both conventional and proposed switches are able to withstand up to 48 dBm RF power in OFF-state and demonstrate identical small- and large-signal response.