An Ultracompact Frequency-Reconfigurable SPDT Switch With 42-dB Isolation

This letter reports a dc-to-7.2 GHz single-pole double-throw (SPDT) switch in 55-nm bulk CMOS technology, aiming to cover the 2.4-/5-/6-GHz bands in IEEE 802.11be (Wi-Fi 7) wireless local area network standards. A coupled-inductive reconfigurable path is built and inserted to achieve low-/high-frequency reconfiguration, which composes two serial coupled inductors and three mode-selection switches bridging the two RF signal branches. The measured SPDT switch features better than 1.3-dB insertion loss, and 42-dB isolation in both the low-frequency mode (dc to 3.6 GHz) and high-frequency mode (3.6–7.2 GHz), which are among the state-of-the-art performance. In addition, to the best of the authors’ knowledge, the occupied core circuit area of 0.022 mm2 is the smallest among similar SPDT switches.