A 5800-μm2 Resistor-Based Temperature Sensor With a One-Point Trimmed Inaccuracy of ±-1.2 °C (3σ) From-50 °C to 105 °C in 65-nm CMOS

This letter describes a compact resistor-based temperature sensor intended for the thermal monitoring of microprocessors and DRAMs. It consists of an RC poly phase filter (PPF) that is read out by a frequency-locked loop (FLL) based on a dual zero-crossing (ZC) detection scheme. The sensor, fabricated in 65-nm CMOS, occupies 5800 mu m(2) and achieves moderate accuracy [+/- 1.2 degrees C (3 sigma)] over a wide temperature range (-50 degrees C to 105 degrees C) after a one-point trim. This is 2x better than the previous compact resistor-based sensors. Operating from 0.85 to 1.3-V supplies, it consumes 32.5-mu A and achieves 2.8-mK resolution in a 1-ms conversion time, which corresponds to a resolution FoM of 0.26 pJ.K-2.