Thermal Reliability of a CMOS-OTA Versus Improving Its Parameters

Abstract

In this study, the relationship between thermal sensitivity of a CMOS operational transconductance amplifier (OTA) and other parameters of the OTA such as gain bandwidth (GBW), DC gain, settling time, slew rate (SR), etc. is analyzed and discussed. For the first time, it is shown that although some techniques such as adaptive biasing and DC gain enhancement can be utilized to improve the transient response of a CMOS-OTA by increasing the input stage’s gain, DC gain, GBW and SR, yet this causes a significant increase in the thermal sensitivities of the CMOS-OTA, so that, the reliability of accurate operation of the CMOS-OTA under variation in ambient temperature effectively decreases. This paper concludes that a reconciliation of the thermal reliability with improvement of the CMOS-OTA parameters should be considered when the CMOS-OTA is designed and implemented. This point is the contribution of this work that has not been considered and addressed in any other works. Simulated results performed using 0.18[Formula: see text][Formula: see text]m SILTERRA CMOS process technology and real experimental results are presented that explicitly verify the theoretical results.