A 28 mK Resolution, -0.45 °C/+0.51 °C Inaccuracy Temperature Sensor Using Dual-Comparator Architecture and...

Area of Science:

• Integrated Circuits
• Sensor Technology
• Semiconductor Devices

Background:

• Accurate temperature monitoring is crucial for modern electronics.
• Existing sensors often face trade-offs between power consumption, range, and precision.
• CMOS technology offers a scalable platform for sensor integration.

Purpose of the Study:

• To develop an all-CMOS temperature sensor with enhanced precision and low power consumption.
• To achieve a wide operational temperature range.
• To improve the resolution and accuracy of temperature measurements.

Main Methods:

• Utilizing MOSFET subthreshold I-V characteristics and self-bootstrapped bias circuits.
• Generating complementary temperature-dependent (CTAT) and proportional to absolute temperature (PTAT) voltages.
• Implementing a dual-comparator voltage-to-time converter (VTC) architecture.
• Employing a control logic unit for precise interval counting.

Main Results:

• Achieved high linearity and sensitivity in temperature sensing.
• The sensor demonstrated an inaccuracy of -0.45 °C/+0.51 °C (3σ) over -40 °C to 130 °C.
• Obtained a high resolution of 28 mK.
• Demonstrated ultra-low power consumption of 503 nW at 27 °C and 1 V.
• Reported a figure of merit (FoM) of 7.9 pJ·K².

Conclusions:

• The proposed all-CMOS temperature sensor effectively meets requirements for high precision and low power.
• The novel VTC and control logic design significantly enhance measurement accuracy and resolution.
• This sensor is suitable for applications demanding efficient and reliable temperature monitoring.