Search

CN-122025501-A - Alternating current control circuit for quadrupole rods of mass spectrometer

CN122025501ACN 122025501 ACN122025501 ACN 122025501ACN-122025501-A

Abstract

The invention discloses an alternating current control circuit for a quadrupole rod of a MASS spectrometer, which comprises a frequency excitation circuit, a negative feedback circuit, a direct current-to-alternating current circuit, an alternating current amplification circuit and an oscillation circuit, wherein the frequency excitation circuit is used for outputting a first excitation signal and a second excitation signal, the negative feedback circuit is used for receiving a MASS# signal sent by an external processor to adjust the alternating voltage amplitude of the quadrupole rod, the direct current-to-alternating current circuit is used for respectively converting positive and negative direct currents into alternating currents according to the received first excitation signal and the second excitation signal, the alternating current amplification circuit is used for respectively amplifying the voltages of the two paths of alternating currents output by the direct current-to-alternating current circuit, the oscillation circuit is used for respectively amplifying the amplified voltages again to form resonance and correspondingly outputting a first oscillation signal and a second oscillation signal, and the power supply circuit is used for connecting the quadrupole rod to supply power. The invention generates resonance through the oscillating circuit to obtain low-loss voltage output, and can dynamically adjust the voltage value which is actually required to be applied, so that the quadrupole rod works stably, and the service life of the circuit is prolonged.

Inventors

  • LI JIE
  • MENG SHUO
  • CAO YONG
  • LI TAO

Assignees

  • 瑞莱谱(杭州)医疗科技有限公司

Dates

Publication Date
20260512
Application Date
20251229

Claims (12)

  1. 1. The alternating current control circuit for the quadrupole rod of the mass spectrometer is characterized by comprising a frequency excitation circuit, a negative feedback circuit, a direct current-to-alternating current circuit, an alternating current amplifying circuit, an oscillating circuit and a power supply circuit, wherein: The frequency excitation circuit is used for outputting a first excitation signal and a second excitation signal; The negative feedback circuit comprises an operational amplifier U32, a capacitor C86, a capacitor C92 and a capacitor C93, wherein the positive power end of the operational amplifier U32 is connected with the positive electrode of a power supply and is grounded through the capacitor C92, the negative power end is connected with the negative electrode of the power supply and is grounded through the capacitor C93, the non-inverting input end of the negative power supply is grounded, the inverting input end of the negative feedback circuit is used for receiving a MASS# signal sent by an external processor so as to adjust the alternating voltage amplitude of a quadrupole rod, the inverting input end of the negative feedback circuit is connected with the output end of the operational amplifier U32 through the capacitor C86, and the output end of the operational amplifier U32 is also used as a REFAIL end for circuit cutting-off protection; the input end of the direct current/alternating current circuit is connected with the output end of the operational amplifier U32 and is used for converting positive and negative direct currents into alternating currents respectively according to the received first excitation signal and second excitation signal; The alternating current amplifying circuit is used for respectively amplifying the voltages of the two paths of alternating currents output by the direct current alternating current circuit; the oscillating circuit is used for amplifying the amplified voltages again to form resonance respectively and correspondingly outputting a first oscillating signal and a second oscillating signal; The power supply circuit comprises a diode D9, a zener diode ZD19, a diode D11, a zener diode ZD20, a connector J7 and a four-stage coil, wherein the four-stage coil comprises a primary coil FIR1 and a secondary coil FIR2, the cathode of the diode D9 is connected with the cathode of the zener diode ZD19, the anode of the diode D9 is respectively connected with a first pin of the connector J7 and is used for receiving the first oscillation signal, the anode of the zener diode ZD19 is connected with a second pin of the connector J7, the cathode of the diode D11 is connected with the cathode of the zener diode ZD20, the anode of the diode D11 is respectively connected with a fourth pin of the connector J7 and is used for receiving the second oscillation signal, the anode of the zener diode ZD20 is respectively connected with a third pin of the connector J7, the second pin of the connector J7 is respectively connected with a third pin, the first pin of the connector J7 and the second pin of the connector J7 are respectively connected with the two ends of the primary coil 1 and the secondary coil 1 and the two ends of the secondary coil FIR2 are respectively connected with the primary coil 1 and the two ends of the secondary coil FIR 2.
  2. 2. The alternating current control circuit for a quadrupole rod of a mass spectrometer of claim 1, wherein the frequency excitation circuit comprises a DC/DC power chip U36, a resistor R155, a crystal oscillator X1, a resistor R270, a capacitor C68, a resistor R268, a trigger U28, a resistor R156, a capacitor C73, a switch SW2, an inverter U31, a capacitor C79, a resistor R269, a resistor R164, a capacitor C140, and a connector J3, wherein: The power input pin of the DC/DC power chip U36 is connected with the power anode, the power output pin is respectively connected with one ends of the resistor R155 and the resistor R270, the grounding pin is connected with 0V voltage, the other end of the resistor R270 is connected with the power anode, the tri-state control pin of the crystal oscillator X1 is connected with the other end of the resistor R155, the power supply pin is connected with the common end of the resistor R155 and the resistor R270 and is connected with 0V voltage through the capacitor C68, the grounding pin is connected with 0V voltage, the clock output pin is connected with 0V voltage through the resistor R268, the first channel clock input zero clearing pin of the trigger U28 and the first channel preset pin are connected with the power anode, the first channel data input pin and the first channel reverse output pin are connected, the first channel clock input pin is connected with the clock output pin of the crystal oscillator X1, the first channel forward output pin is connected with the movable contact of the switch SW2 through the resistor R156, the grounding pin is connected with 0V voltage, the second channel reverse output pin and the second channel data input zero clearing pin and the second channel output signal are connected with the second channel output pin and the second channel output signal of the switch SW2, and the second channel output signal is connected with the second channel positive power input signal and the power input of the power source signal is connected with the second channel positive input pin and the power output pin of the second channel signal of the switch SW 2; The signal input pin of the inverter U31 is respectively connected with one ends of the capacitor C140, the resistor R269 and the resistor R164, the signal output pin is connected with a static contact of the switch SW2, the grounding pin is connected with 0V voltage, the power supply anode pin is connected with the power supply anode and the other end of the resistor R269, the two pins of the connector J3 are respectively grounded and connected with the other end of the capacitor C140, the two ends of the capacitor C79 are respectively connected with 0V voltage and the power supply anode pin of the inverter U31, and the other end of the resistor R164 is connected with the grounding pin of the inverter U31.
  3. 3. An alternating current control circuit for a quadrupole rod of a mass spectrometer as set forth in claim 1, wherein: the direct current-to-alternating current circuit comprises a resistor R179, a resistor R173, a resistor R184, a potentiometer VR10, a resistor R125, an NPN triode Q2, a diode D6, a resistor R56, a capacitor C85, an NPN triode Q7, a diode D12, a resistor R57, a capacitor C99 and a four-way analog switch U30, wherein one end of the resistor R179 is connected with the output end of the operational amplifier U32, the other end is respectively connected with the resistor R173 and one end of the resistor R184, a pin of a signal output end of the potentiometer VR10 is connected with a power supply cathode through the resistor R125, a pin of a power supply anode is connected with the other end of the resistor R173, a pin of a power supply cathode is connected with the other end of the resistor R184, a collector of the NPN triode Q2 is connected with a power supply anode, an emitter is connected with the anode of the diode D6, a base is connected with a pin of a power supply anode of the potentiometer VR10, the collector of the NPN triode Q7 is connected with the positive electrode of the diode D12, the base is connected with the negative electrode pin of the power supply of the potentiometer VR10, the first pin and the sixteenth pin of the four-way analog switch U30 are used for receiving a first excitation signal, the eighth pin and the ninth pin are used for receiving a second excitation signal, one end of the resistor R56 and one end of the capacitor C85 are connected with the negative electrode of the diode D6 and the second pin of the four-way analog switch U30, the other end of the resistor R56 and one end of the capacitor C85 are connected with the negative electrode of the power supply and the sixth pin of the four-way analog switch U30, one end of the resistor R57 and one end of the capacitor C99 are connected with the negative electrode of the diode D12 and the tenth pin of the four-way analog switch U30, the other end of the resistor R56 and the fourteenth pin of the four-way analog switch U30 are connected, the third pin and the seventh pin of the four-way analog switch U30 and the eleventh pin and the fifteenth pin are connected with each other, and the third pin and the eleventh pin of the four-way analog switch U30 are also connected with the alternating current amplifying circuit.
  4. 4. An alternating current control circuit for a quadrupole rod for a mass spectrometer as set forth in claim 3, wherein: the alternating current control circuit for the quadrupole of the mass spectrometer further comprises a rectifier bridge circuit, wherein the rectifier bridge circuit comprises a diode group D8, a capacitor C151, an inductor L4, a capacitor C87, a resistor R176, a capacitor C84, a capacitor C88, a diode group D13, a capacitor C152, an inductor L5, a capacitor C100, a resistor R202, a capacitor C98 and a capacitor C101, the diode group D8 comprises a first Schottky diode and a second Schottky diode, the positive electrode of the first Schottky diode is respectively connected with the negative electrode of the second Schottky diode and the third pin of the four-way analog switch U30, one end of the inductor L4 is respectively connected with the negative electrode of the first Schottky diode and the positive electrode of the second Schottky diode, the other end of the inductor L4 is connected with 0V voltage through the capacitor C151, the other end of the inductor L4 is sequentially connected with 0V voltage through the resistor R176, the capacitor C84 and the capacitor C88, the diode group D13 comprises a third Schottky diode and a fourth Schottky diode, the positive electrode of the third Schottky diode is respectively connected with the negative electrode of the fourth Schottky diode and the eleventh pin of the four-way analog switch U30, one end of the inductor L5 is respectively connected with the negative electrode of the third Schottky diode and the positive electrode of the fourth Schottky diode, the voltage is connected with 0V through the capacitor C152, the other end of the inductor L5 is connected with 0V through the resistor R202, the capacitor C98 and the capacitor C101 in sequence, the voltage is connected with 0V through the capacitor C100, the common end of the capacitor C84 and the capacitor C88 is also connected with the positive input end of the alternating current amplifying circuit as the positive output end of the rectifier bridge circuit, the capacitor C98 and the capacitor C101 are also used as the inverting output end of the rectifier bridge circuit to be connected with the negative input end of the alternating current amplifying circuit.
  5. 5. The alternating current control circuit for a quadrupole rod of a mass spectrometer of claim 4, wherein the alternating current amplification circuit comprises a first push-pull circuit, a second push-pull circuit, a third push-pull circuit, and a fourth push-pull circuit, wherein: The first push-pull circuit comprises a resistor R171, a resistor R180, a resistor R186, an NPN triode Q5 and a capacitor C82, wherein the base electrode of the NPN triode Q5 is connected with the common end of the capacitor C84 and the capacitor C88, the collector electrode is connected with the positive electrode of a power supply and is connected with 0V voltage through the capacitor C82, the emitter electrode is connected with 0V voltage through the resistor R186, the two ends of the resistor R171 are respectively connected with the base electrode and the collector electrode of the NPN triode Q5, the two ends of the resistor R180 are respectively connected with the base electrode of the NPN triode Q5 and the 0V voltage end of the resistor R186, and the common end of the resistor R171 and the resistor R180 is used as the positive input end of the alternating current amplifying circuit; The second push-pull circuit comprises a resistor R200, a resistor R205, a resistor R209, an NPN triode Q9 and a capacitor C95, wherein the base electrode of the NPN triode Q9 is connected with the common end of the capacitor C98 and the common end of the capacitor C101, the collector electrode is connected with the positive electrode of a power supply and is connected with 0V voltage through the capacitor C95, the emitter electrode is connected with 0V voltage through the resistor R209, the two ends of the resistor R200 are respectively connected with the base electrode and the collector electrode of the NPN triode Q9, the two ends of the resistor R205 are respectively connected with the base electrode of the NPN triode Q9 and the 0V voltage end of the resistor R209, and the common end of the resistor R200 and the resistor R205 serves as the negative input end of the alternating current amplifying circuit; The third push-pull circuit comprises a capacitor C80, a capacitor C91, a diode D5, a diode D7, a diode D10, a resistor R165, a resistor R189, a resistor R166, a resistor R177, an NPN triode Q1, a PNP triode Q6, a capacitor C83 and a capacitor C149, wherein one ends of the capacitor C80 and the capacitor C91 are respectively connected with an emitter of the NPN triode Q5, a base of the NPN triode Q1 is respectively connected with the other end of the capacitor C80 and an anode of the diode D5, a collector is connected with a power supply positive electrode and is connected with 0V voltage through the capacitor C149, an emitter is respectively connected with a base and a collector of the NPN triode Q1 through the resistor R166, an emitter of the PNP triode Q6 is respectively connected with a common end of the resistor R166 and the capacitor C83 through the resistor R177, a base is respectively connected with the other end of the capacitor C91 and a negative end of the diode D10, a collector of the PNP triode D10 is respectively connected with the other ends of the capacitor D10 and the collector of the diode D10 in series connection with the capacitor C83 in sequence; The fourth push-pull circuit comprises a capacitor C94, a capacitor C109, a diode D14, a diode D16, a diode D17, a resistor R194, a resistor R216, a resistor R204, a resistor R211, an NPN triode Q8, a PNP triode Q12, a capacitor C102 and a capacitor C150, wherein one ends of the capacitor C94 and the capacitor C109 are respectively connected with an emitter of the NPN triode Q9, a base of the NPN triode Q8 is respectively connected with the other end of the capacitor C94 and an anode of the diode D14, a collector is connected with 0V voltage, the emitter is respectively connected with one end of the capacitor C102 through the resistor R204, two ends of the resistor R194 are respectively connected with a base and a collector of the NPN triode Q8, an emitter of the PNP triode Q12 is respectively connected with a public end of the resistor R204 and the capacitor C102, the base is respectively connected with the other end of the capacitor C109 and a cathode of the diode D17, the collector is respectively connected with a power supply, the collector is respectively connected with the other end of the capacitor C16 and the base of the diode D16 and the collector of the capacitor D16, and the diode D12 are respectively connected with two ends of the capacitor D12 in series.
  6. 6. The alternating current control circuit for a quadrupole rod of a mass spectrometer of claim 1, wherein the oscillating circuit comprises a biasing circuit, a first transformer excitation circuit, and a second transformer excitation circuit, wherein: the bias circuit comprises a resistor R174, a resistor R199, a potentiometer VR4, a potentiometer VR6, a resistor R210, a capacitor C148, a resistor R213, a capacitor C110 and a zener diode ZD25, wherein two ends of the resistor R174 are respectively connected with one end of the resistor R199 and the positive output end of the alternating current amplifying circuit, two ends of the capacitor C148 are respectively connected with the other end of the resistor R199 and the power supply negative electrode pin of the potentiometer VR6, the signal output pin of the potentiometer VR4 is connected with the public end of the resistor R174 and the resistor R199, the power supply positive electrode pin is connected with the power supply positive electrode pin of the potentiometer VR6, the negative electrode of the zener diode ZD25 is connected with the power supply positive electrode through the resistor R213, the capacitor C110 and the zener diode ZD25 are connected in parallel, the negative electrode of the zener diode ZD25 is also connected with the power supply positive electrode pin of the potentiometer VR6, the positive electrode is connected with the power supply negative electrode pin of the potentiometer VR6, the signal output pin of the potentiometer VR4 and the potentiometer VR6 is connected with the power supply negative electrode pin of the potentiometer VR6, the voltage V0 is also connected with the capacitor C102 through the voltage pin of the resistor R210, and the public end of the resistor R102 is connected with the voltage of the resistor R102; The first transformer excitation circuit comprises a resistor R169, an N-channel power type field effect transistor Q3, a voltage stabilizing diode ZD15, a voltage stabilizing diode ZD16, a capacitor C89, a resistor R182, a resistor R170, an N-channel power type field effect transistor Q4, a voltage stabilizing diode ZD17, a voltage stabilizing diode ZD18, A capacitor C90 and a resistor R183, wherein the grid electrode of the N-channel power type field effect transistor Q3 is connected with the positive output end of the alternating current amplifying circuit through the resistor R169, the drain electrode is connected with the drain electrode of the N-channel power type field effect transistor Q4, the source electrode is connected with the negative electrode of the voltage stabilizing diode ZD16, the voltage stabilizing diode ZD15 and the voltage stabilizing diode ZD16 are reversely connected in series, the negative electrode of the voltage stabilizing diode ZD15 is respectively connected with the positive output end of the alternating current amplifying circuit and the negative electrode of the voltage stabilizing diode ZD17, the capacitor C89 and the resistor R182 are connected in parallel, the two ends of the capacitor C89 are respectively connected with the negative electrode of the voltage stabilizing diode ZD16 and the ground, the grid electrode of the N-channel power type field effect transistor Q4 is connected with the negative electrode of the voltage stabilizing diode ZD17 through the resistor R170, the drain electrode is also used as the positive output end of the oscillating circuit to output the first oscillating signal and is connected with the positive electrode of the diode D9, the source electrode is connected with the negative electrode of the voltage stabilizing diode ZD18, the capacitors ZD17, the capacitors C89 and the two ends of the capacitors ZD18 are respectively connected in parallel, the two ends of the capacitors ZD18 and the two ends of the voltage stabilizing diode Z16 are reversely connected in series, the voltage stabilizing circuit and the voltage stabilizing resistor R183 is connected with the voltage stabilizing resistor Z207 and the voltage stabilizing resistor Z16 respectively, and the voltage stabilizing resistor is connected in parallel, N-channel power type field effect transistor Q10, zener diode ZD21, zener diode ZD22, capacitor C107, resistor R214, resistor R208, N-channel power type field effect transistor Q11, zener diode ZD23, zener diode ZD24, The grid electrode of the N-channel power type field effect transistor Q10 is connected with the negative output end of the alternating current amplifying circuit through the resistor R207, the drain electrode is connected with the drain electrode of the N-channel power type field effect transistor Q11, the source electrode is connected with the negative electrode of the voltage stabilizing diode ZD22, the voltage stabilizing diode ZD21 and the voltage stabilizing diode ZD22 are reversely connected in series, the negative electrode of the voltage stabilizing diode ZD21 is respectively connected with the negative output end of the alternating current amplifying circuit and the negative electrode of the voltage stabilizing diode ZD23, the capacitor C107 and the resistor R214 are connected in parallel, two ends of the capacitor C107 are respectively connected with the negative electrode of the voltage stabilizing diode ZD22 and the ground, the grid electrode of the N-channel power type field effect transistor Q11 is connected with the negative electrode of the voltage stabilizing diode ZD23 through the resistor R208, the drain electrode is also used as the negative output end of the oscillating circuit to output the second oscillating signal and is connected with the positive electrode of the diode D11, the source electrode is connected with the negative electrode of the voltage stabilizing diode ZD24, the capacitors ZD23 and the two ends of the voltage stabilizing diode ZD24 are respectively connected in parallel, and the two ends of the capacitor ZD24 and the capacitor C24 are reversely connected in series with the ground.
  7. 7. The alternating current control circuit for a mass spectrometer quadrupole rod as set forth in claim 1, further comprising a conditioning circuit comprising a common mode inductance L6, a high voltage supply circuit, a high voltage loop circuit, a loss current feedback circuit, and a first filter circuit, wherein: The first pin and the second pin of the common-mode inductor L6 form a first winding, the third pin and the fourth pin form a second winding, and the fourth pin of the common-mode inductor L6 is grounded through a first filter circuit and is connected with the second pin of the connector J7; The high-voltage power supply circuit comprises a capacitor C96, a capacitor C97, a diode D15, a relay RL1, a connector JP1, a diode D21, a resistor R30, a resistor R29, a resistor R275 and an NPN triode Q17, wherein a third pin of the common-mode inductor L6 is connected with the negative electrode of the diode D15, and is connected with 0V voltage through the capacitor C96 and the capacitor C97 which are connected in parallel, a first pin of the relay RL1 is respectively connected with the positive electrode of a power supply and the negative electrode of the diode D21, a second pin is respectively connected with the positive electrode of the diode D21 and one end of the resistor R30, a seventh pin is connected with the positive electrode of the diode D15, a collector electrode of the NPN triode Q17 is connected with the other end of the resistor R30, an emitter electrode is connected with 0V voltage, a base electrode is connected with the high voltage through the resistor R29, two ends of the resistor R275 are respectively connected with the base electrode and the emitter electrode of the NPN triode Q17, a second pin of the connector JP1 is respectively connected with the positive electrode of the sixth pin and the eighth pin of the relay RL1, and the sixth pin is connected between the sixth pin and the sixth pin of the relay RL1 and the eighth pin is connected with the positive electrode of the relay 1; The high-voltage loop circuit comprises a capacitor C103 and a capacitor C104, wherein a second pin of the common-mode inductor L6 is connected with 0V voltage through the capacitor C103 and the capacitor C104 which are connected in parallel and is used as an RF-end for external 96V negative electrode access; The loss current feedback circuit comprises a resistor R219, a resistor R217, a resistor R75, a capacitor C137 and a connector J2, wherein a first pin of the common mode inductor L6 is grounded through the resistor R219 and the resistor R217 which are connected in parallel and used as an RFI end for measuring the energy loss of the circuit, the first pin of the common mode inductor L6 is grounded through the resistor R75 and the capacitor C137 in sequence, and two pins of the connector J2 are connected with the ground and a common end of the resistor R75 and the capacitor C137 respectively.
  8. 8. The alternating current control circuit for a quadrupole rod of a mass spectrometer according to claim 7, wherein the first filter circuit comprises an electrolytic capacitor CE3, an electrolytic capacitor CE4, a capacitor C105 and a capacitor C106, wherein the positive electrode of the electrolytic capacitor CE3, the positive electrode of the electrolytic capacitor CE4, one end of the capacitor C105 and one end of the capacitor C106 are all connected with the fourth pin of the common mode inductance L6, and the negative electrode of the electrolytic capacitor CE3, the negative electrode of the electrolytic capacitor CE4, the other end of the capacitor C105 and the other end of the capacitor C106 are all grounded.
  9. 9. The alternating current control circuit for a quadrupole rod of a mass spectrometer of claim 7, wherein the adjusting circuit further comprises an indicating circuit, the indicating circuit comprises a resistor R206, a resistor R212 and a Light Emitting Diode (LED) 1, the fourth pin of the common mode inductor L6 is connected with the positive electrode of the Light Emitting Diode (LED) 1 sequentially through the resistor R206 and the resistor R212, and the negative electrode of the Light Emitting Diode (LED) 1 is grounded.
  10. 10. The alternating current control circuit for a quadrupole rod of a MASS spectrometer of claim 1, wherein the negative feedback circuit further comprises a resistor R168, a capacitor C81, a resistor R167 and a resistor R172, wherein the resistor R167 is connected in parallel with the resistor R172 and has one end connected to an inverting input of the operational amplifier U32 and the other end connected to one end of the resistor R168 and to a voltage of 0V through the capacitor C81, and wherein the other end of the resistor R168 is connected to the processor to receive the MASS# signal.
  11. 11. The alternating current control circuit for a quadrupole rod of a MASS spectrometer according to claim 1, further comprising a first tuning circuit, wherein the first tuning circuit comprises a resistor R175, a resistor R178 and a resistor R181, wherein the processor sends out a first trimming signal Co, a second trimming signal Be and an enabling signal RFRESET, and wherein the first trimming signal Co, the second trimming signal Be and the enabling signal RFRESET sequentially correspond to the trimming of the MASS# signal by inputting the resistor R175, the resistor R178 and the resistor R181 to the inverting input terminal of the operational amplifier U32.
  12. 12. The alternating current control circuit for a mass spectrometer quadrupole rod of claim 1, further comprising a second tuning circuit comprising resistor R185, resistor R187, resistor R190, resistor R191, resistor R274, resistor R193, resistor R192, resistor R195, resistor R196, resistor R197, resistor R198, resistor R203, potentiometer VR3, encoder rotary switch SW1, and connector J9, wherein: The signal output end pin of the potentiometer VR3 is connected with one end of the resistor R185, the positive electrode pin of the power supply is connected with the C-th pin of the encoder rotary switch SW1, the negative electrode pin of the power supply is connected with 0V voltage, the C-th pin of the encoder rotary switch SW1 is used as an RRF end for being connected with the alternating voltage of a quadrupole rod which is actually output to form closed loop control, the closed loop control is respectively connected with one end of the resistor R187 and the first pin of the connector J9, the first pin of the encoder rotary switch SW1 is connected with one end of the resistor R193, the second pin is connected with one end of the resistor R274 through the resistor R192, the fourth pin is connected with one end of the resistor R191, the eighth pin is connected with one end of the resistor R190, the resistor R185, the resistor R187, the resistor R190, the resistor R191, the resistor R274 and the other end of the resistor R193 are all connected with the reverse input end of the operational amplifier U32, and the first pin, the second pin, the fourth pin and the fourth pin are sequentially connected with the resistor R197 and the resistor R9 through the corresponding to the resistor R197, the third pin and the resistor R25 and the third pin is connected with the resistor R25 and the J9.

Description

Alternating current control circuit for quadrupole rods of mass spectrometer Technical Field The invention belongs to the technical field of mass spectrometers, and particularly relates to an alternating current control circuit for a quadrupole rod of a mass spectrometer. Background A mass spectrometer is a high-sensitivity, high-resolution and high-specificity analysis instrument for detecting chemical composition of a sample, such as a triple quadrupole mass spectrometer (also called a tandem quadrupole mass spectrometer or the like), which is one of mass spectrometers capable of performing MS/MS analysis, has a relatively simple structure and is inexpensive, and thus is widely used. Quadrupole rods are an important component of mass spectrometers for improving ion transport efficiency. The existing quadrupole rods all work by adopting alternating current, ions are forced to move in an electric field formed by the quadrupole rods so as to achieve the aim of ion screening, direct current is generally input firstly, the direct current is required to be converted into alternating current, but the prior art lacks real-time control on a power supply for providing an electric field, if the real-time control on the alternating current is lacking, the working stability of the quadrupole rods is difficult to ensure, and the inside of an instrument is easy to damage. Disclosure of Invention The invention aims to solve the problems, and provides an alternating current control circuit for a quadrupole rod of a mass spectrometer, which is capable of generating resonance through an oscillating circuit to obtain low-loss voltage output, dynamically adjusting the voltage value actually needed to be applied, stabilizing the operation of the quadrupole rod and being beneficial to prolonging the service life of the circuit. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: the invention provides an alternating current control circuit for a quadrupole rod of a mass spectrometer, which comprises a frequency excitation circuit, a negative feedback circuit, a direct current-to-alternating current circuit, an alternating current amplifying circuit, an oscillating circuit and a power supply circuit, wherein: A frequency excitation circuit for outputting a first excitation signal and a second excitation signal; The negative feedback circuit comprises an operational amplifier U32, a capacitor C86, a capacitor C92 and a capacitor C93, wherein the positive power end of the operational amplifier U32 is connected with the positive electrode of a power supply and grounded through the capacitor C92, the negative power end is connected with the negative electrode of the power supply and grounded through the capacitor C93, the non-inverting input end is grounded, the inverting input end is used for receiving a MASS# signal sent by an external processor so as to adjust the alternating voltage amplitude of a quadrupole rod, and the inverting input end is connected with the output end of the operational amplifier U32 through the capacitor C86, and the output end of the operational amplifier U32 is also used as a REFAIL end for circuit cut-off protection; The input end of the direct current-to-alternating current circuit is connected with the output end of the operational amplifier U32 and is used for converting positive and negative direct currents into alternating currents respectively according to the received first excitation signal and the received second excitation signal; The alternating current amplifying circuit is used for respectively amplifying the voltages of the two paths of alternating currents output by the direct current alternating current circuit; The oscillating circuit is used for amplifying the amplified voltages again to form resonance respectively and correspondingly outputting a first oscillating signal and a second oscillating signal; The power supply circuit comprises a diode D9, a voltage stabilizing diode ZD19, a diode D11, a voltage stabilizing diode ZD20, a connector J7 and a four-stage coil, wherein the four-stage coil comprises a primary coil FIR1 and a secondary coil FIR2, the cathode of the diode D9 is connected with the cathode of the voltage stabilizing diode ZD19, the anode of the diode D9 is respectively connected with the first pin of the connector J7 and is used for receiving a first oscillation signal, the anode of the voltage stabilizing diode ZD19 is connected with the second pin of the connector J7, the cathode of the diode D11 is connected with the cathode of the voltage stabilizing diode ZD20, the anode of the diode D11 is respectively connected with the fourth pin of the connector J7 and is used for receiving a second oscillation signal, the anode of the voltage stabilizing diode ZD20 is respectively connected with the third pin of the connector J7, the second pin of the connector J7 is connected with the third pin, the first pin and the second pi