A current-voltage conversion circuit and method with input bias and active filtering

Abstract

The invention discloses a current-to-voltage conversion circuit with input bias and active power filtering effects and a current-to-voltage conversion method. The current-to-voltage conversion circuit with the input bias and active power filtering effects comprises an operational amplifier A1 and a bias current source; after being in parallel connection with the bias current source, a current signal (Is) is connected to a reverse input end of the operational amplifier A1; a forward input end of the operational amplifier A1 is connected with the ground; an output end of the operational amplifier A1 is connected with a reverse input end of the operational amplifier A1 through a capacitor C1 and is connected to a parallel-connection node between the bias current source and the current signal (Is) through a negative feedback resistor R3; and the node is in parallel connection with a capacitor C2 in a grounding manner. Input bias is implemented through the current source, active power filtering and current-to-voltage conversion are implemented through the operational amplifier, the circuit is simple, the cost is low, and the application prospect is high.

Description

technical field [0001] The invention relates to a current-voltage conversion circuit and method with input bias and active filtering, and belongs to the technical field of electronic circuits. Background technique [0002] Because the current signal has a good anti-interference ability, many sensors in the industrial control field output current signals. However, due to the high cost performance of multi-channel unipolar ADCs, in order to meet the range requirements of unipolar ADCs, it is necessary in many occasions The bipolar current signal from the sensor is biased and converted into a unipolar signal, and low-pass filtering is required to meet the requirements of the sampling theorem. [0003] At present, the typical scheme is that the current signal output by the sensor I s First, the voltage conversion of the signal is completed through the current-voltage conversion circuit, and then the offset of the signal is completed through an adder, such as figure 1 As shown,...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to overcome the need for multi-chip operational amplifiers when the existing bipolar current signal is biased and converted into a unipolar signal, which occupies a large space on the printed circuit board, which is not conducive to the cost control and miniaturization of the circuit design needs

Images