초록 ▼

The invention includes a direct current energy source monitor which automatically detects the nominal voltage of the direct current energy source to which it is attached. The invention further includes a direct current energy source monitor which is self-powered from the direct current energy source

The invention includes a direct current energy source monitor which automatically detects the nominal voltage of the direct current energy source to which it is attached. The invention further includes a direct current energy source monitor which is self-powered from the direct current energy source being monitored. The multiple nominal voltage direct current energy source monitor includes an analog-to-digital converter configured to measure voltage from a direct current energy source being monitored and generate a digital output corresponding thereto. The apparatus includes a programmable control device configured to receive the digital output from the analog-to-digital converter and to look up a nominal voltage corresponding to the digital output, and is further configured to calculate a relative charge of the direct current energy source as compared to a full charge on the direct current energy source. The direct current energy source monitor can include a voltage controlled oscillator configured to receive the voltage of the direct current energy source being monitored and generate a frequency output proportional to the received voltage. The programmable control device is configured use the frequency output to determine the received voltage from the direct current energy source. The direct current energy source monitor preferably includes a calibration circuit configured to periodically calibrate the voltage controlled oscillator. The calibration circuit is configured to generate known voltages which are supplied to the voltage controlled oscillator. The voltage controlled oscillator is governed by a transfer function, wherein its output is a function of the input. The coefficients of the transfer function are calculated by the programmable control device based on the known voltages applied to the voltage controlled oscillator and the output produced by the voltage controlled oscillator in response thereto.

대표청구항 ▼

[ We claim:] [1.]1. A multiple nominal voltage direct current energy source monitor, comprising:an analog-to-digital converter configured to measure voltage from a direct current energy source being monitored by the voltage monitor and generate a digital output corresponding thereto; anda programmab

[ We claim:] [1.]1. A multiple nominal voltage direct current energy source monitor, comprising:an analog-to-digital converter configured to measure voltage from a direct current energy source being monitored by the voltage monitor and generate a digital output corresponding thereto; anda programmable control device configured to receive the digital output from the analog-to-digital converter and to look up a nominal voltage from a range of nominal voltages anticipated to be encountered by the direct current energy source monitor, the nominal voltage corresponding to the digital output, and further configured to calculate a relative charge of the direct current energy source as compared to a full charge on the direct current energy source.