Program-controlled multi-channel variable resistor and resistance value adjustment and control method thereof

Abstract

The invention relates to a program-controlled multi-channel variable resistor and a resistance value adjustment and control method thereof. The variable resistor comprises a communication interface, a multi-channel resistance output interface, a single-chip microcomputer and at least one single channel, wherein the communication interface is connected with an upper computer of a control system, each single channel comprises a digital potentiometer and an electro-static discharge protection chip which form a series branch, communication is carried out between the single-chip microcomputer and a serial port conversion module by a universal asynchronous receiver / transmitter (UART) three-wire interface mode, the single-chip microcomputer and the digital potentiometers are arranged through an I<2>C communication mode, or the tap position or the resistance value of the current digital potentiometer are read. The adjustment and control method comprises the following steps of 1) testing a serial port; 2) carrying out direct program-controlled reading and adjustment on the resistance value of the digital potentiometer of an appointed channel; and 3) periodically calibrating the resistance value of the digital potentiometer of each channel by a multimeter. The program-controlled multi-channel variable resistor and the resistance value adjustment and control method thereof have the advantages of simplicity in composition, convenience in use and accurate and reliable resistance value, the embedded software of the single-chip microcomputer can use the resistance value correction linear coefficient of each channel to automatically correct the resistance value, and the accuracy of the resistance value of the variable resistor is guaranteed.

Description

technical field [0001] The invention relates to resistance adjustment, in particular to a program-controlled multi-channel variable resistor and its resistance value adjustment and control method. Background technique [0002] For the adjustment and control of the resistance value, the existing traditional methods are realized by mechanical displacement or rotation, such as sliding rheostats and rotary adjustable variable potentiometers. In recent years, it has been widely used in digital potentiometers including instruments and meters, computers and communication equipment, household appliances, health care products and industrial control fields. Although it has small size, high adjustment accuracy, no noise, no mechanical wear, extremely long life and The advantage of being able to read and write data, the adjustment and control of its resistance value can only be done through I 2 The C communication protocol is implemented, and the resistance value cannot be directly con...

AI Technical Summary

Problems solved by technology

In recent years, it has been widely used in digital potentiometers including instruments and meters, computers and communication equipment, household appliances, health care products and industrial control fields. Although it has small size, high adjustment accuracy, no noise, no mechanical wear, extremely long life and The advantage of being able to read and write data, the adjustment and control of its resistance value can only be done through I 2 The C communication protocol is implemented, and it is impossible to directly control and adjust its resistance value by cooperating with software running on personal computers (PersonalComputer, abbreviated as PC), laptops, tablet computers, smart phones and smart terminals.

In addition, there is often an error between the resistance value of the digital potentiometer and the nominal value. This error will change with the passage of time and needs to be calibrated. Otherwise, it is difficult to guarantee the accuracy of its resistance value.

At present, there is no multi-channel variable resistor for direct program control through computer or intelligent terminal

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