A Low Voltage BJT-Based Temperature Sensor with Duty Cycle Modulated Output with FOM Resolution of about 1.4pJ. ◦C2 and Inaccuracy of ±0.11 ◦C (3σ) from −55 ◦C to 130 ◦C

Dehban Rahimabad, Mohtaram; Heidari, Ali

doi:10.22124/cse.2025.31195.1112

Document Type : Original Article

Authors

Department of Electrical Engineering, University of Guilan, Rasht, Iran

https://doi.org/10.22124/cse.2025.31195.1112

Abstract

This paper presents a low voltage BJT-based smart temperature sensor with duty cycle modulated output and inaccuracy of ±0.11 ◦C (3σ) and FOM resolution of about 1.4pJ. ◦C² from −55◦C to 130◦C. This sensor can work with a supply voltage of 1.5V. It uses a BJT-based front-end to generate a proportional to absolute temperature voltage (V_PTAT) and a complementary to absolute temperature voltage (V_CTAT), which are then modulated to a duty-cycle output. Adding an integrator before the Schmitt trigger has increased the range of input changes of the Schmitt trigger. As a result, the hysteresis of the Schmitt trigger can be increased and it has better noise immunity. Implemented in a standard 0.18-µm CMOS process, the sensor has an active area of about 0.64mm² and can work with 1.5V from -55◦C to 130◦C with an inaccuracy of ±0.11◦C (3σ). Power consumption is about 45uW.

Keywords

References

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Computational Sciences and Engineering

A Low Voltage BJT-Based Temperature Sensor with Duty Cycle Modulated Output with FOM Resolution of about 1.4pJ. ◦C2 and Inaccuracy of ±0.11 ◦C (3σ) from −55 ◦C to 130 ◦C

References

References

Volume 5, Issue 1
April 2025
Pages 15-24

A Low Voltage BJT-Based Temperature Sensor with Duty Cycle Modulated Output with FOM Resolution of about 1.4pJ. ◦C2 and Inaccuracy of ±0.11 ◦C (3σ) from −55 ◦C to 130 ◦C

References

References

Volume 5, Issue 1April 2025Pages 15-24

Volume 5, Issue 1
April 2025
Pages 15-24