Capacitor measurement device and method thereof

Abstract

The invention relates to capacitor measurement device and method thereof. The device comprises a four-threshold digital comparator, a variable gain amplifier, a size variable positive and negative constant flow source, a rapid analog / digital converter, a microprocessor and a display, wherein the microprocessor receives output signals of the four-threshold digital comparator and the analog / digitalconverter and outputs measurement results to the display; the microprocessor selects the positive and negative constant flow source and the amplification factor of the amplifier according to the capacity of a measured capacitor; and voltage on the measured capacitor amplified by the variable gain amplifier is measured by the rapid analog / digital converter, and the measurement results are output to the four-threshold digital comparator. In the capacitor measurement method, by the constant flow forward charge and back discharge of the measured capacitor, the microprocessor figures out the measurement result of a primary capacitance value according to time interval of the forward charge and back discharge between two threshold values preset by the four-threshold digital comparator, the numerical value of the constant flow source and the amplification factor of the variable gain amplifier. The invention greatly reduces the measurement time of the capacitor under the condition of using smaller charge / discharge current and eliminates the influence of the absorption effect of the capacitor on the measurement accuracy by the installation of the four-threshold digital comparator.

Description

technical field [0001] The invention relates to a device and method for measuring capacitance, in particular to provide a method and device suitable for fast and accurate measurement of capacitance, especially for fast measurement of large capacitance. The method and device for measuring capacitance of the present invention can also effectively avoid the influence of capacitance absorption effect. Background technique [0002] Capacitance measurement has become an important feature of measuring instruments such as digital multimeters. Current capacitance measurement techniques are unsatisfactory not only because of the long measurement time required to wait for the unknown capacitor to charge, but also because of the absorption effect of the capacitor affecting measurement accuracy. It is desirable to provide a new measurement method, expand the larger measurement range of capacitance and realize fast and accurate measurement. [0003] It is well known that the current i f...

AI Technical Summary

Problems solved by technology

Current capacitance measurement techniques are unsatisfactory, not only due to the long measurement time required to wait for the unknown capacitor to charge, but also the absorption effect of the capacitor affecting the measurement accuracy

Images