A Sensor Signal Digitalization Module for High-Temperature Environment Applications
Goran Horak, Darko Vasić, Vedran Bilas, O. Krkac · Conference proceedings - IEEE Instrumentation/Measurement Technology Conference · 2006
The electronic instrumentation which operates in the high-temperature environment of an oil well should be specially designed. Analog-to-digital converters are critical components in well-logging applications with only few high-temperature-rated commercial components on the market. Our objective is to realize a custom A/D conversion module for multichannel well-logging applications following the smart-sensor concept and using proven, reliable and available electronic components. This paper presents a simple and robust digitalization module which utilizes a pulse-width modulator in combination with a phase-locked loop. We are presenting results of a high-temperature functional evaluation of a demonstration prototype implemented using commercial-and industrial-grade integrated components in combination with high-temperature rated passive components. The module's operating range is defined by the 5V unipolar supply voltage. The effective number of bits of the digitalization module is between 10 and 13 over the temperature range 25-175°C.