Radio frequency power supply circuit suitable for four-level rod mass spectrometer

Abstract

The invention relates to a radio frequency power supply circuit suitable for a four-level rod mass spectrometer. The circuit has high signal transmission efficiency, high control precision and a low space radiation magnetic field. The structure of the circuit is simple and hardware cost is greatly saved. The circuit comprises a sine wave oscillation circuit, a frequency modulation circuit, an amplification circuit, a boosting transformer and a feedback loop, wherein the sine wave oscillation circuit is connected to the frequency modulation circuit and is used for generating a sine wave voltagesignal and inputting the sine wave voltage signal to the frequency modulation circuit; the frequency modulation circuit is connected to the amplification circuit and is used for modulating the frequency of the sine wave voltage signal; the amplification circuit is connected to the input side winding of the boosting transformer and is used for amplifying the modulated sine wave voltage signal; theboosting transformer is used for further amplifying the modulated sine wave voltage signal; and the feedback loop is used for collecting a sampling signal from the boosting transformer, converting apulsating alternating current voltage into a pulsating direct current voltage through a bridge rectifier circuit, then carrying out difference value operation with a backward-stage reference voltage and feeding a difference value signal back to the frequency modulation circuit so as to realize the stable control of an output voltage.

Description

technical field [0001] The invention relates to the technical field of radio frequency power supply, in particular to a radio frequency power supply circuit suitable for a quadrupole mass spectrometer. Background technique [0002] Mass spectrometers can be used for quantitative and qualitative detection of substances and have efficient and accurate measurement characteristics, and are widely used in biology, medical treatment, food and other fields. As one of the core components of the mass spectrometer, the quadrupole realizes the separation of ions with different mass-to-charge ratios through the action of an alternating electric field. In an alternating electric field environment, ions will oscillate according to the strength of the electric field, and only ions with a specific mass-to-charge ratio can pass through the electric field stably. When the electric field intensity on the quadrupole is constant, ions with relatively small masses will be subjected to a strong e...

AI Technical Summary

Problems solved by technology

In order to ensure a sufficiently high Q value, the RF power step-up transformer used in conventional quadrupole mass spectrometers usually uses an air frame, resulting in a large RF power supply and too many coil windings, which brings a lot of inconvenience to installation and commissioning

Furthermore, the RF power sampling feedback circuit usually uses resistance sampling or optocoupler isolation sampling, resulting in complex circuits and low stability

Moreover, the quadrupole mass spectrometer usually uses an analog chip to realize PFM control, and its control accuracy is difficult to guarantee, and the consistency of large-scale production is poor

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