Circuit and method for accurately measuring resistor in Wheatstone bridge by using computer

Abstract

The invention discloses a circuit and a method for accurately measuring a resistor in a Wheatstone bridge by using a computer. The circuit comprises a PC, an embedded processor, the Wheatstone bridge,a bridge switching circuit and a voltage comparison circuit; the PC is configured to send a control instruction, adjust bridge arm resistance, judge bridge balance, collect measurement data, and calculate data; the Wheatstone bridge is composed of a first comparison resistor, a second comparison resistor, a resistor to be tested, and a resistance source, and is configured to adjust the resistancevalue according to the instruction transmitted by the PC; the bridge switching circuit is configured to provide a circuit branch so as to change the positions of the first comparison resistor and thesecond comparison resistor in the Wheatstone bridge; and the voltage comparison circuit is configured to collect a voltage difference between an upper and a lower end of the bridge and output the voltage difference to the embedded processor. The circuit disclosed by the invention effectively solves the problems of cumbersome measurement operation and large measurement error in the process of resistance measurement, makes the processing of the data more intuitive, scientific and precise, and also facilitates later application requiring precise resistance correlation.

Description

technical field

[0001] The invention relates to the technical field of electronic measurement, in particular to a circuit and method for accurately measuring resistance in a Wheatstone bridge by using a computer. Background technique

[0002] At present, the method of measuring the resistance of the Wheatstone bridge in the university physics laboratory is to use manual measurement. By adjusting the bridge arm to make the ammeter zero, record the resistance value of the knob contact resistance box, and use the elimination method to calculate the resistance twice. The square root of multiplying the box readings is the measured resistance value. There are two types of problems in such measurement: (1) Due to the use of human eyes to observe the resistance readings, it is time-consuming and laborious, and there are also errors caused by human experiments, the work is too cumbersome, and the errors are too large. In terms of data processing, human processing or human input into...

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