On-Chip MOSFET Temperature Sensor for Electrical Characterization of RF Circuits

This letter proposes a new sensor circuit to measure on-chip low-frequency temperature changes that have information about electrical high-frequency figures of merit of a radio frequency (RF) circuit. The proposed sensor circuit uses a metal-oxide-semiconductor field-effect transistor (MOSFET) as a temperature sensing device, which is then connected to a band-pass filter that amplifies the low-frequency temperature signal generated by the RF circuit under test (CUT). Simulations in 65 nm CMOS technology show that such a sensor circuit can extract the center frequency (2.47 GHz) of a RF power amplifier (PA) by measuring on-chip temperature changes at 1 kHz.