A DC to 67-GHz 40-nm CMOS SP4T Switch for Cryogenic S-Parameter Measurement and Calibration

To improve the accuracy and precision of the cryogenic S-parameter measurement and calibration, a dc to 67-GHz single-pole-four-throw (SP4T) switch is proposed as a core circuitry in the measurement system. This broadband switch is designed following a procedure that incorporates LC-ladder low-pass filter theory, enabling the straightforward synthesis of a single-pole-multi-throw switch with a desired response. The implemented SP4T switch achieves isolation of > 35 dB and insertion loss of < 2 dB in the 4-K cryogenic measurements from dc to 20 GHz (the upper limit of our cryo-measurement facility). With a low power consumption of merely 0.6 μW, the proposed switch is suitable for various multiplexing and microwave measurement applications operating at cryogenic temperatures.