Precision Analog Signal Conditioning Semiconductors for Operation in Very High Temperature Environments

When designing signal chains for systems exposed to high temperature environments, analog signal processing ICs are needed to enable precision sensor measurements. However, as ambient operating temperatures increase beyond the typical extended-industrial +125°C limit, the performance characteristics of analog semiconductors are strongly impacted by the effects of temperature on circuit design, packaging, and the underlying fabrication process. In this paper we introduce two new precision analog components, an operational amplifier and voltage reference, rated for very high temperature operation. We then discuss the steps taken to ensure their performance at high temperature is robust and can be maintained over a limited lifetime. Finally, we demonstrate these devices utilized in an example application: a constant current source for temperature sensor signal conditioning.