Accurate resistance testing is a very necessary process. In many precision instruments, the requirement for the precision of resistor is very high. When purchasing resistor products, R & D personnel need to evaluate and test the resistor. By accurately measuring the resistance parameters, they determine whether the resistance meets the requirements of the equipment.
The methods and systems for accurately measuring resistance usually adopt the method of multi-point test, which can not only eliminate the influence of the stability of test performance on the test results, but also improve the accuracy of the test results. Furthermore, it can directly judge whether the test results are affected by other abnormal factors, that is, to judge whether the test results are abnormal or not, thus improving the test efficiency.
 

The structure diagram of the system for accurately measuring resistance value includes the control module, detection module, function fitting module, resistance value acquisition module and the judgment module, and the judgment module consist of intercept acquisition unit and the judgment unit. The control module is used for continuously applying a plurality of preset voltages or a plurality of preset currents on the resistance to be tested. The detection module is used to obtain the detection current flowing through the resistance to be tested under each preset voltage, or the detection voltage at both ends of the resistor to be tested under each preset current.

 

 

The function fitting module is used for the linear fitting of the preset voltage and the detecting current, or for the linear fitting of the detecting voltage and the preset current to generate the linear fitting function. The resistance acquisition module is used to obtain the slope of the linear fitting function, and the slope is the resistance value of the resistance to be tested.

The intercept acquisition unit is used to obtain the cross-section of the linear fitting function when a plurality of preset voltages are continuously applied on the resistor to be tested, or the longitudinal intercept of the linear fitting function when a plurality of preset currents are continuously applied on the resistance under test.
 
The judging unit is used to compare the transverse intercept with the size of the first preset value, to judge whether the measurement result of the resistance value to be tested is abnormal or not, or to compare the longitudinal intercept with the size of the second preset value, based on the comparison results.