A Fully Monolithic 6H-SiC JFET-Based Transimpedance Amplifier for High-Temperature Capacitive Sensing

作者：Soong Chia Wei^*; Garverick Steven L; Fu Xiao An; Patil Amita C; Mehregany Mehran

来源：IEEE Transactions on Electron Devices, 2013, 60(12): 4146-4151.

DOI：10.1109/TED.2013.2287601

• Harsh environment
• high temperature
• junction gate field-effect transistor
• SiC
• transimpedance amplifier

This paper introduces a high-temperature fully monolithic high gain-bandwidth 6H-SiC transimpedance amplifier for capacitive sensor interfacing. The amplifier achieves a gain of 235 k Omega and a bandwidth of 0.61 MHz at room temperature. Results from the proof-of-concept measurements performed with variable capacitors demonstrate the functionality of differential capacitive sensing across a wide temperature range, up to 450 degrees C. The amplifier also exhibits a stable gain with respect to power supply variations. At elevated temperatures, the amplifier exhibits increasing gain with decreasing bandwidth, as expected. At 450 degrees C, the gain and bandwidth are 774 k Omega and 0.17 MHz, respectively. This is the first report that demonstrates the capacitive sensing capability of a SiC transimpedance amplifier, and represents a critical step toward the goal of integrating a sensing element with its interface circuit in a single monolithic device for operation at extreme temperatures.

• 出版日期2013-12