High-precision voltage-current converter

Abstract

The invention discloses a high-precision voltage-current converter, which comprises a voltage-controlled current source and an output circuit coupled with the voltage-controlled current source, and ischaracterized in that the output circuit comprises a current limiting circuit, and a current output node is coupled to the current limiting circuit; wherein the voltage-controlled current source comprises an operational amplifier, a mirror current source, a first field effect transistor and a setting resistor; the first field effect transistor is coupled between the mirror current source and thesetting resistor, and the setting resistor is grounded; a first node is arranged between the first field effect transistor and the setting resistor; the non-inverting input end of the operational amplifier is coupled with a voltage input node, the inverting input end of the operational amplifier is coupled with the first node, and the output end of the operational amplifier is coupled with the grid electrode of the first field effect transistor; and the input end of the current limiting circuit is coupled with the mirror current source. The high-precision voltage-current converter is small insize, low in cost, good in linearity, high in precision, strong in anti-interference capability and high in reliability.

Description

technical field [0001] The invention relates to the technical field of electronic circuits, in particular to a high-precision voltage-current converter. Background technique [0002] Voltage / current conversion, that is, V / I conversion, is to convert the input voltage signal into a current signal that satisfies a certain relationship. The converted current is equivalent to a constant current source with adjustable output, and its output current should be able to maintain stability without changing changes with load changes. Generally speaking, the voltage-current conversion circuit is realized in the form of negative feedback, which can be current series negative feedback or current parallel negative feedback, which is mainly used in industrial control and many sensor applications. With the development of electronic technology, higher requirements are put forward for the V / I conversion circuit, especially in the industrial field, the standard signals commonly used by various...

AI Technical Summary

Problems solved by technology

At present, V / I conversion is mostly realized by adding IC and several discrete components, but due to the low precision and poor linearity of IC, and the addition of multiple discrete components, the solution is large in size, poor in reliability, poor in linearity, and low in precision.

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