A high temperature, 12-bit-time-domain sensor interface based on injection locked oscillator

A novel resistive sensor interface for high temperature applications is presented. It is based on a time domain architecture using Injection Locked Oscillators as phase shifters that results in higher temperature hardness and simpler circuits. The system depends on the relative accuracy instead of its absolute properties and doesn't suffer from temperature variations. The proposed circuit is designed using 0.18 μm partially depleted silicon on insulator technology. Simulations have shown a maximum variation of the output lower than ±0.5%, over a temperature ranging from -40°C to 250°C.