Energy efficiency and accuracy are important specifications of CMOS temperature sensors. BJT -based sensors achieve state-of-the-art accuracy , while Wheatstone-bridge (WhB) sensors achieve lower accuracy but state-of-the-art energy efficiency , . This paper presents a WhB sensor that is read out by an energy-efficient continuous-time delta-sigma modulator (CTDSM). Compared to , , the modulator achieves better energy efficiency with the help of a return-to-CM (RCM) DAC and an OTA with a tail-resistor linearization scheme. Moreover, better accuracy is achieved by embedding the DAC in the bridge and by using more sensitive silicided-diffusion resistors instead of silicided-poly resistors. Compared to the state-of-the-art , the proposed sensor achieves a 2× improvement in resolution FoM (10fJ.K2), and a 2× improvement in inaccuracy (0.4° C(3σ) from -55° C to 125°C after a 1-point trim).
|Title of host publication||2020 IEEE International Solid-State Circuits Conference, ISSCC 2020|
|Number of pages||3|
|Publication status||Published - 2020|
|Event||2020 IEEE International Solid-State Circuits Conference, ISSCC 2020 - San Francisco, United States|
Duration: 16 Feb 2020 → 20 Feb 2020
|Conference||2020 IEEE International Solid-State Circuits Conference, ISSCC 2020|
|Period||16/02/20 → 20/02/20|