Inventors:
Nick S. Kapsokavathis - Shelby Township, Utica County MI
Carl D. Wright - Noblesville IN
Stephen P. Sanders - Millington MI
Nick M. Johnson - Los Altos CA
Chun F. Cheah - San Francisco CA
Assignee:
General Motors Corp. - Detroit MI
National Semiconductor Corp. - Santa Clara CA
International Classification:
G01R 2726
G01N 2722
Abstract:
A fuel composition sensor provides to a voltage divider comprising sensor and reference capacitors a voltage which oscillates between two voltages at a comparatively low frequency, such as 6 KHz, for lower power dissipation, but which switches fast to produce periodic fast voltage changes across the voltage divider to produce voltage spikes at the junction of the capacitors indicative of the capacitance ratio and thus of fuel composition.