Analog resistor circuit

Abstract

The invention discloses an analog resistor circuit, and belongs to the technical field of analog resistors, and the circuit comprises a sampling resistor circuit, wherein the sampling resistor circuitis connected in series with an analog-to-digital conversion circuit that is connected in series with a control circuit, the control circuit is connected in series with a digital-to-analog conversioncircuit that is connected in series with a voltage output circuit, the sampling resistor circuit samples and amplifies the excitation current I input from external equipment and provides the excitation current I to the analog-to-digital conversion circuit to convert the current value into a digital quantity, and the control circuit calculates the required output voltage value U according to the analog resistor value R and the excitation current value I, and controls the digital-to-analog conversion circuit to output the voltage value, so as to control the voltage output circuit to output the set output resistance. The analog resistor circuit provided by the invention realizes the digital setting of the resistor through the analog-to-digital conversion circuit and the digital-to-analog conversion circuit, realizes the real-time measurement of the excitation current through the sampling circuit and the analog-to-digital conversion circuit, and can still guarantee the output accuracy under the condition of different excitation current.

Description

technical field [0001] The invention relates to a circuit, in particular to a circuit for simulating resistance, and belongs to the technical field of simulating resistance. Background technique [0002] Resistor is a linear element. Under certain conditions, the current flowing through a resistor is proportional to the voltage across the resistor, that is, Ohm's law: R=U÷I. The unit of resistance is ohm, which is represented by the symbol "Ω". [0003] As one of the most basic electronic components, resistors are widely used in analog circuits. In practical applications, the resistance value of resistors often needs to be adjusted. Generally, resistance boxes, sliding resistors, and digital potentiometers are used. Resistance boxes are By switching the gear switch to change the resistance value and number of series resistors to obtain a certain resistance value, the electrical instrument is large in size and relatively expensive. It is generally used as a standard resistanc...

AI Technical Summary

Problems solved by technology

[0003] As one of the most basic electronic components, resistors are widely used in analog circuits. In practical applications, the resistance value of resistors often needs to be adjusted. Generally, resistance boxes, sliding resistors, and digital potentiometers are used. Resistance boxes are By switching the gear switch to change the resistance value and number of series resistors to obtain a certain resistance value, the electrical instrument is large in size and relatively expensive. It is generally used as a standard resistance for laboratory or precision circuit measurement. Mechanical potential The resistance value of the resistor is adjustable, and the price is cheaper than the resistance box. The disadvantage is that the resistance value needs to be measured by a multimeter to read the resistance value, and the resolution is low, and the resistance value has a large temperature drift.

[0004] With the popularization of digital circuits, digital potentiometers gradually replace mechanical potentiometers. Digital potentiometers control output resistance through digital input, but at present there are still large resistance values ​​and low resolution, which are not suitable for fine adjustment of low resistance values.

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