High-precision high-voltage current source circuit

Abstract

The invention discloses a high-precision high-voltage current source circuit. The high-precision high-voltage current source circuit comprises a logic control unit, a high-voltage Boost circuit, a negative pressure generation circuit, a DAC circuit, a high-voltage floating operation and amplification circuit, a constant-current source circuit, a bridge-H chopper circuit, and an overcurrent overload protection circuit. By adopting the high-precision high-voltage current source circuit, the problems of the traditional Howland current source that the stability is poor, the circuit is easy in saturation state, the output current is relatively low, the efficiency is relatively low, the influence of the operation and amplification Ibias is great, the four peripheral matching resistors are difficult in consistency and the like can be solved. The high-precision high-voltage current source circuit is capable of realizing the fine stepper adjustment for the current, large in current output range, high in load capacity, flexible and variable in circuit parameters and relatively low in requirement for the consistence of peripheral parameters.

Description

technical field [0001] The invention belongs to the field of electronic circuits and relates to a high-precision high-voltage current source circuit. Background technique [0002] Current sources, a vast field. The most basic current source circuit is a simple current source or a current mirror current source composed of triodes, see figure 1 ; After the popularization and application of integrated operational amplifier circuits, a constant current source circuit composed of operational amplifier units combined with resistors, namely the Howland current source, appeared. figure 2 , the circuit model provides guidance for the follow-up constant current source circuit based on the op amp topology. [0003] In addition to adding negative feedback, the Howland current source also has a positive feedback link. In the Howland current source, Rh3 and Rh4 form a negative feedback network, and the output is fed back to the inverting input terminal. The feedback coefficient is Rh4 / ...

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