All-CMOS low supply voltage scattered thermal monitoring front-end

Presented is a low-voltage all-CMOS scattered thermal monitoring architecture front-end designed in a 0.5 μm process. To support low-voltage operation for scaled CMOS technologies, MOSFETs operating in the subthreshold region and an amplifier with a bulk-driven technique are used. To reduce the offset error caused by device mismatches, gain boosting, dynamic offset cancellation and dynamic element matching methods are adopted. The sensor node occupies an area of 90 × 70 μm². The measured minimum supply voltage was 1.1 V over a -55 to 125°C temperature range. The front-end was chamber tested and the performances are reported. Experiments demonstrated the multi-corner thermal monitor detecting on-chip temperature gradients from 1.2 to 26°C/mm.