A circuit for improving the resolution of an oxygen sensor in a vehicle exhaust system. The circuit expands a limited output voltage range of an oxygen sensor to full voltage range of an analog-to-digital (A/D) converter, prior to input of the expanded signal into the A/D converter. Utilization of the...http://www.google.es/patents/US6374817?utm_source=gb-gplus-sharePatente US6374817 - Application of OP-AMP to oxygen sensor circuit
