A low-power battery ampere-hour meterA digital device has been developed to meter the current drain of a battery in ampere hours. The device consists of a voltage controlled oscillator (VCO), a frequency divider, an accumulator, and a liquid crystal display. A voltage proportional to load current is converted into a clock signal whose pulse rate is scaled by the frequency divider to the desired engineering units. Final output pulses are counted and displayed. The use of MOSFET and CMOS integrated circuits allows continuous battery-powered operation over a 3-month time period to an accuracy of +/- 2 percent. The instrument will find application where accurate monitoring of battery charge/discharge status is required over long time intervals.
Document ID
19930070380
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Tripp, John S. (NASA Langley Research Center Hampton, VA, United States)
Schott, Timothy D. (NASA Langley Research Center Hampton, VA, United States)
Date Acquired
August 16, 2013
Publication Date
January 1, 1993
Publication Information
Publication: In: International Instrumentation Symposium, 39th, Albuquerque, NM, May 2-6, 1993, Proceedings (A93-54351 24-35)