A time-of-flight mass spectrometer control circuit

Abstract

This invention discloses a control circuit for a time-of-flight mass spectrometer, relating to the field of mass spectrometry instrumentation. It includes an FPGA main control circuit on an FPGA system control board, a DAC control circuit on a DAC control board, and an ADC control circuit on an ADC control board. A power supply system provides power to the DAC control circuit, ADC control circuit, I / O output control circuit, and FPGA main control circuit. The DAC control circuit, ADC control circuit, and I / O output control circuit exchange data with the FPGA main control circuit. The FPGA main control circuit is connected to a PC-based mass spectrometer. The I / O output control circuit is connected to a power amplifier transistor, which is connected to voltage output circuits with different voltage values. This invention redesigns and optimizes the circuits of the discrete module circuit boards, integrating the discrete modules into a highly integrated control circuit board, further improving the real-time performance and reliability of the acquired data.

Description

Technical Field

[0001] This invention relates to the field of mass spectrometry instrument technology, specifically to a time-of-flight mass spectrometer control circuit. Background Technology

[0002] The control system of a time-of-flight mass spectrometer (TOF-MS) involves many analog voltages that require real-time monitoring. If multiple ADC chips were used to directly acquire these signals, the entire circuitry would become extremely large and complex. Furthermore, mass spectrometers are high-precision instruments, requiring precise control of the output voltages of multiple high-voltage power supplies during normal operation. This necessitates low noise in the front-end control circuitry.

[0003] The analyzer of a mass spectrometer requires a high vacuum environment to function properly, and also requires a 20kV high voltage as the ion acceleration voltage. The high vacuum environment ensures that the analyzer can function properly, and also ensures the discharge distance of the accelerating electrode, preventing high-voltage discharge from occurring in the instrument. However, problems can still occur during instrument use, such as damage to the fore-stage oil pump or vacuum molecular pump, which can lead to insufficient vacuum in the instrument. This can eventually cause the instrument to discharge, and may result in other issues such as high-voltage breakdown of the circuit board or power supply.

[0004] Currently, the circuit architecture used in the industry adopts discrete circuit modules to control their respective functional modules. This leads to the following problems: First, a complex power supply system, as different main control chips require different power supply voltages; second, each module requires more communication interfaces, increasing communication time and reducing the real-time performance of data acquisition; third, the discrete modules are assembled in different locations, increasing wiring and reducing the reliability of the instrument. Summary of the Invention

[0005] This invention addresses the problems existing in the prior art by providing a time-of-flight mass spectrometer control circuit.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A time-of-flight mass spectrometer control circuit includes a power supply system, an FPGA system control board, a DAC control board, an ADC control board, and an I / O output control circuit. The FPGA system control board has an FPGA main control circuit, the DAC control board has a DAC control circuit, and the ADC control board has an ADC control circuit. The power supply system supplies power to the DAC control circuit, ADC control circuit, I / O output control circuit, and FPGA main control circuit. The DAC control circuit, ADC control circuit, and I / O output control circuit are set independently in pairs, and each of them exchanges data with the FPGA main control circuit. The FPGA main control circuit is also connected to a PC mass spectrometer. The I / O output control circuit is connected to a power amplifier tube via an optocoupler, and the power amplifier tube is connected to voltage output circuits with different voltage values.

[0008] Based on the above technical solution, the ADC control circuit further includes an analog switch, an impedance matching module, an analog-to-digital converter chip, an isolation transmission chip module, a filter capacitor module, and a power supply circuit. After the signal is processed by the analog switch, it is output to the impedance matching module, and then the signal is output to the analog-to-digital converter chip. The converted digital signal communicates with the microcontroller through the isolation transmission chip module.

[0009] Based on the above technical solution, the output circuit of the ADC control board is further connected to the high vacuum gauge vacuum acquisition circuit, the low vacuum gauge vacuum acquisition circuit, the acquisition card power supply monitoring circuit, and the preamplifier power supply monitoring circuit, respectively.

[0010] Based on the above technical solution, the preamplifier power supply monitoring circuit further includes a first resistor, a second resistor, a first capacitor, a second capacitor, a power chip, a first isolation amplifier, a third capacitor, and a fourth capacitor. One end of the first resistor is connected to the power output terminal, the second capacitor, and the power chip, and the other end of the first resistor is connected to the second resistor, the first capacitor, and the first isolation amplifier. One end of the second resistor and the first capacitor are grounded together, and the first capacitor is also connected to the first isolation amplifier. The third capacitor, the second capacitor, and the power chip are grounded together, and the power chip is also connected to the third capacitor and the first isolation amplifier. The first isolation amplifier is connected to the fourth capacitor.

[0011] Based on the above technical solution, the preamplifier power supply monitoring module further monitors the preamplifier power supply circuit, which includes a power supply unit, a first filter capacitor unit, and a first power supply output interface. The power supply unit is connected to the first power supply output interface, the power supply unit is connected to the first filter capacitor unit, and the first filter capacitor unit is connected to the first power supply output interface.

[0012] Based on the above technical solution, the power supply monitoring circuit of the acquisition card further includes a third resistor, a fourth resistor, a fifth capacitor, a sixth capacitor, a second isolation amplifier, and a seventh capacitor. One end of the third resistor is connected to the power supply, the fifth capacitor, and the second isolation amplifier, and the other end of the third resistor is connected to the fourth resistor, the sixth capacitor, and the second isolation amplifier. One end of the fifth capacitor is grounded, and one end of the sixth capacitor is connected to the fourth resistor, grounded, and the second isolation amplifier. The second isolation amplifier is connected to the seventh capacitor.

[0013] Based on the above technical solution, the power supply monitoring circuit of the acquisition card monitors the power supply control output circuit of the acquisition card. The power supply control output circuit of the acquisition card includes a power supply output unit, a second filter capacitor unit, and a second power supply output interface. The power supply output unit is connected to the second power supply output interface, the second power supply output interface is connected to the second filter capacitor unit, and the second filter capacitor unit is connected to the power supply output unit.

[0014] Based on the above technical solution, the I / O output control circuit is further composed of a first I / O output circuit, a second I / O output circuit, a third I / O output circuit and a fourth I / O output circuit.

[0015] Based on the above technical solution, the high vacuum gauge vacuum acquisition circuit further includes a high vacuum gauge power supply switch control circuit, a high vacuum gauge comparison circuit, an eighth capacitor, and a high vacuum gauge output interface. The high vacuum gauge power supply switch control circuit outputs the real-time vacuum simulation signal to the high vacuum gauge comparison circuit through the high vacuum gauge output interface.

[0016] Based on the above technical solution, the high vacuum gauge power supply switch control circuit further includes a first optocoupler and a first switch. One end of the first optocoupler is connected to a fifth resistor. The fifth resistor is connected to an output pin of the microcontroller to output a signal. The first optocoupler is also connected to the first switch. One pin of the first switch is also connected to a sixth resistor. The sixth resistor is connected to a seventh resistor and the gate of the first MOSFET. The source of the first MOSFET is connected to the seventh resistor, the ninth capacitor, and the tenth capacitor. The drain of the first MOSFET is connected to the first inductor and the eleventh capacitor. The eleventh capacitor is connected to the twelfth capacitor, the thirteenth capacitor, another pin of the first switch, the negative terminal of the first photodiode, and the first diode. The first diode is connected to the eighth resistor, the thirteenth capacitor, the twelfth capacitor, and the first inductor. The eighth resistor is connected to the positive terminal of the first photodiode.

[0017] Based on the above technical solution, the high vacuum gauge comparator circuit further includes a first operational amplifier, wherein the first operational amplifier is connected to one end of a ninth resistor, the other end of the ninth resistor is connected to the base of a first transistor, the emitter of the first transistor is grounded, the collector of the first transistor is connected to a tenth resistor, the tenth resistor is connected to a second optocoupler, the second optocoupler is connected to the emitter of a second transistor, the collector of the second transistor is connected to a power supply, the base of the second transistor is connected to an eleventh resistor, the eleventh resistor is connected to a twelfth resistor and the output pin of the first operational amplifier, the twelfth resistor is connected to a thirteenth resistor, the first operational amplifier, a fourteenth resistor and a fourteenth capacitor, wherein the fourteenth resistor and the fourteenth capacitor are both grounded, and the thirteenth resistor is connected to a reference voltage.

[0018] Based on the above technical solution, the low vacuum gauge vacuum acquisition circuit further includes a low vacuum gauge power supply switch control circuit, a low vacuum gauge output interface, a shorting resistor, a reference generation circuit, and a low vacuum gauge comparison circuit. The low vacuum gauge power supply switch control circuit is activated to supply power to the low vacuum gauge vacuum acquisition circuit, and the signal is output from the low vacuum gauge output interface to the interface of the FPGA system control board. Then, the vacuum value is fed back to the reference generation circuit and the low vacuum gauge comparison circuit in sequence from the low vacuum gauge output interface.

[0019] Based on the above technical solution, further, the low vacuum gauge power supply switch control circuit includes a third optocoupler, wherein one end of the third optocoupler is connected to the fifteenth resistor, the fifteenth resistor is connected to an output pin of the microcontroller to output a signal, the third optocoupler is also connected to the second switch, one pin of the second switch is also connected to the sixteenth resistor, the sixteenth resistor is connected to the seventeenth resistor and the gate of the second MOSFET, the source of the second MOSFET is connected to the seventeenth resistor, the seventeenth resistor is connected to the negative terminal of the second diode, the fifteenth capacitor and the sixteenth capacitor, the other ends of the parallel fifteenth capacitor and the sixteenth capacitor are grounded together, and the positive terminal of the second diode is grounded; the drain of the second MOSFET is connected to the second inductor and the seventeenth capacitor, the seventeenth capacitor is connected to the eighteenth capacitor, the nineteenth capacitor, the second switch, the negative terminal of the second photodiode and the third diode, the third diode is connected to the eighteenth resistor, the nineteenth capacitor, the eighteenth capacitor and the second inductor, and the eighteenth resistor is connected to the positive terminal of the second photodiode.

[0020] Based on the above technical solution, further, the low vacuum gauge comparator circuit includes a second operational amplifier, wherein the inverting input terminal of the second operational amplifier is connected to the nineteenth resistor, the nineteenth resistor is connected to the twentieth resistor, the non-inverting input terminal of the second operational amplifier is connected to the twenty-first resistor, the twenty-second resistor, and the second operational amplifier itself, the twenty-first resistor is connected to a reference voltage and the twenty-third resistor, the twenty-third resistor is connected to the twenty-fourth resistor, and the twenty-fourth resistor is grounded; the second operational amplifier is connected to the twenty-fifth resistor, the twenty-fifth resistor is connected to the base of transistor Q13, the collector of transistor Q13 is connected to the power supply, and the collector of transistor Q13... The emitter is connected to the fourth optocoupler, which is also connected to the twenty-eighth resistor. The twenty-eighth resistor is connected to the collector of the third transistor, whose emitter is grounded. The base of the third transistor is connected to the twentieth resistor. The fourth optocoupler is also connected to the twenty-sixth resistor, the collector of the fourth transistor, and the collector of the fifth transistor. The emitter of the fifth transistor is grounded, and its base is connected to the twenty-seventh resistor. The twenty-seventh resistor is connected to an output pin of the microcontroller to output a signal. The base of the fourth transistor is connected to the twenty-ninth resistor, which is also connected to an output pin of the microcontroller to output a signal.

[0021] Based on the above technical solution, the FPGA main control circuit further includes a power supply generation circuit and a power supply input port. The power supply input port supplies power to the power supply generation circuit. The power supply generation circuit includes a switching power supply. The switching power supply is connected to a capacitor assembly, the negative terminal of the fourth diode, and the third inductor. The positive terminal of the fourth diode is grounded. The third inductor is connected to the switching power supply, the twentieth capacitor, the twenty-first capacitor, the twenty-second capacitor, and the power supply VCC. The twenty-second capacitor is connected to the twenty-first capacitor, the twenty-first capacitor, ground, and the switching power supply.

[0022] Based on the above technical solution, the DAC control circuit is further composed of several digital-to-analog converters arranged in parallel, and the parallel-arranged digital-to-analog converters operate independently.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The present invention redesigns and optimizes the circuit of each discrete module circuit board, integrates the discrete modules into a control circuit board with a high degree of integration, and replaces the main control chip with a faster FPGA chip, thereby further improving the real-time performance and reliability of the acquired data.

[0025] (2) This invention uses a combination of multiplexer and ADC chip and adopts the idea of ​​time-division acquisition. The multiplexer uses a 16:1 model chip, so that 16 analog signals can be monitored. The signal acquisition uses a high-precision ADC chip with a sampling rate greater than 40Kps. Although the time-division acquisition method is adopted, the acquisition time of a single channel is extremely short, so the feedback signal of the mass spectrometer can be monitored in real time.

[0026] (3) The present invention uses a separate digital-to-analog converter chip for each high-voltage power supply. The main advantages are: 1 / The DAC chips operate independently and there is no crosstalk between each chip; 2 / Better output voltage noise; 3 / Each DAC chip can be controlled independently.

[0027] (4) In order to ensure the high voltage power supply is shut down, the present invention also sets up a vacuum protection circuit in the circuit. The basic idea is to compare the vacuum signal and the preset reference voltage through the operational amplifier. When the vacuum level is insufficient, the power supply enable of the high voltage power supply is immediately shut down, thereby realizing the rapid shutdown of the high voltage and protecting the instrument.

[0028] (5) The present invention has a higher degree of integration, reduces the use of wires, improves the aesthetics of the instrument, and enhances the reliability of the instrument; the lower-level machine has a faster operating speed and more reliable performance; it improves the utilization rate of existing materials and reduces the requirements for material procurement. Attached Figure Description

[0029] Figure 1 This is a flowchart illustrating the overall process of this invention.

[0030] Figure 2 This is a circuit diagram of the ADC control circuit of the present invention;

[0031] Figure 3 This is a circuit diagram of the analog-to-digital converter chip of the present invention;

[0032] Figure 4 This is a circuit diagram of the first isolated transmission chip of the present invention;

[0033] Figure 5 This is a circuit diagram of the second isolated transmission chip of the present invention;

[0034] Figure 6 This is a circuit diagram of the first filter capacitor of the present invention;

[0035] Figure 7 This is a circuit diagram of the second filter capacitor of the present invention;

[0036] Figure 8 This is a circuit diagram of the first power supply of the present invention;

[0037] Figure 9 This is a circuit diagram of the second power supply of the present invention;

[0038] Figure 10 This is a circuit diagram of the third power supply of the present invention;

[0039] Figure 11 This is a circuit diagram of the power supply monitoring circuit for the preamplifier of this invention;

[0040] Figure 12 This is a circuit diagram of the power supply for the preamplifier of the present invention;

[0041] Figure 13 This is a circuit diagram of the first filter capacitor unit of the present invention;

[0042] Figure 14 This is a circuit diagram of the power supply and monitoring circuit for the data acquisition card of this invention;

[0043] Figure 15 This is a circuit diagram of the power supply control output circuit for the data acquisition card of this invention;

[0044] Figure 16 This is a circuit diagram of the second filter capacitor unit of the present invention;

[0045] Figure 17 This is the first I / O output circuit diagram of the present invention;

[0046] Figure 18 This is a circuit diagram of the second I / O output of the present invention;

[0047] Figure 19 This is a circuit diagram of the pulse and power supply interface output of the present invention;

[0048] Figure 20 This is the third I / O output circuit diagram of the present invention;

[0049] Figure 21 This is the fourth I / O output circuit diagram of the present invention;

[0050] Figure 22 This is the +24V power supply control circuit for the high-voltage power supply of the present invention.

[0051] Figure 23 This is the circuit diagram of the eighth capacitor of the present invention;

[0052] Figure 24 This is the high vacuum gauge comparison circuit diagram of the present invention;

[0053] Figure 25 This is a circuit diagram of the high vacuum gauge power supply switch control circuit of the present invention;

[0054] Figure 26 This is the circuit diagram of the high vacuum gauge output interface of the present invention;

[0055] Figure 27 This is a circuit diagram of the high vacuum gauge comparison threshold reference circuit of the present invention;

[0056] Figure 28 This is a circuit diagram of the low-vacuum gauge power supply switch control circuit of the present invention;

[0057] Figure 29 This is the circuit diagram of the low vacuum gauge output interface of the present invention;

[0058] Figure 30 This is the circuit diagram of capacitor C68 of the present invention;

[0059] Figure 31 This is a circuit diagram of the short-circuit resistor of the present invention;

[0060] Figure 32 This is a reference generation circuit diagram for the present invention;

[0061] Figure 33 This is the circuit diagram for the low vacuum gauge comparison of the present invention;

[0062] Figure 34 This is a circuit diagram showing the communication between the RS232 serial port module controlled by the FPGA of this invention and the PC.

[0063] Figure 35 This is a circuit diagram of one of the temperature acquisition modules of the present invention;

[0064] Figure 36 This is a circuit diagram of another temperature acquisition module in this invention;

[0065] Figure 37 This is a circuit diagram of the power supply input port of the present invention;

[0066] Figure 38 The circuit diagram for power supply generation in this invention is shown. Detailed Implementation

[0067] The present invention will be further described and illustrated below with reference to the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly, provided that there is no mutual conflict.

[0068] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. Technical features in the various embodiments of the present invention can be combined accordingly without mutual conflict.

[0069] In the description of this invention, it should be understood that when an element is considered to be "connected" to another element, it can be a direct connection to the other element or an indirect connection, i.e., an intermediate element is present. Conversely, when an element is said to be "directly" connected to another element, no intermediate element is present. In the description of this invention, it should be understood that the terms "first" and "second" are used only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" and "second" may explicitly or implicitly include at least one of that feature.

[0070] Example

[0071] Combination Figure 1 As shown, a time-of-flight mass spectrometer control circuit is provided, comprising a power supply system, an FPGA system control board, a DAC control board, an ADC control board, and an I / O output control circuit. The FPGA system control board is equipped with an FPGA main control circuit, the DAC control board is equipped with a DAC control circuit, and the ADC control board is equipped with an ADC control circuit. The power supply system provides power to the DAC control circuit, ADC control circuit, I / O output control circuit, and FPGA main control circuit respectively. The DAC control circuit, ADC control circuit, and I / O output control circuit are set independently in pairs, and the DAC control circuit, ADC control circuit, and I / O output control circuit exchange data with the FPGA main control circuit respectively. The FPGA main control circuit is also connected to a PC mass spectrometer. The I / O output control circuit is connected to a power amplifier tube through an optocoupler, and the power amplifier tube is connected to voltage output circuits with different voltage values. The output circuit of the ADC control board is connected to at least one voltage output circuit, which includes at least a +5V voltage output circuit, a +12V voltage output circuit, and a +24V voltage output circuit. The output circuit of the ADC control board is connected to control the high vacuum gauge vacuum acquisition circuit, the low vacuum gauge vacuum acquisition circuit, the acquisition card power supply monitoring circuit, the power supply voltage monitoring circuit, the power supply current monitoring circuit, and the preamplifier power supply monitoring circuit. It should be noted in this embodiment that circuit components connected to the same terminal with the same letter, symbol, or name are considered different circuit components connected to the same terminal. For example, if some different circuit components are all connected to +24VIN3, then these circuit components can be connected to the same terminal.

[0072] Specifically, the ADC control circuit includes an analog switch, an impedance matching module, an analog-to-digital converter chip, an isolation transmission chip module, a filter capacitor module, and a power supply circuit module. After the signal is processed by the analog switch, it is output to the impedance matching module, and then to the analog-to-digital converter chip. The converted digital signal communicates with the microcontroller through the isolation transmission chip module. Specifically, in conjunction with... Figure 2As shown, the ADC control circuit includes an analog switch U5, which is a 1:16 analog switch. It can monitor the input interfaces of 16 signals and output the signals to the impedance matching module for buffering and impedance matching. That is, the ADC control circuit can use the multi-channel function of the analog switch to separately control the high vacuum gauge vacuum acquisition circuit, the low vacuum gauge vacuum acquisition circuit, the acquisition card power supply monitoring circuit, the power supply voltage monitoring circuit, the power supply current monitoring circuit, and the preamplifier power supply monitoring circuit. Figure 2 and Figure 3 The combined circuit can monitor the power supply voltage and current. The output signal of the analog switch U5 is connected to the input pin IN+ of the operational amplifier U27 through the output pin 28, and resistors R16 and R58 are connected in series between them. Pin 1 of the analog switch U5 is connected to Vcc, and pin 27 is connected to Vee. One end of resistor R16 is grounded. The operational amplifier U27 can be selected from the OP07 chip. The input pin IN- of the operational amplifier U27 is connected to one end of resistor R55, and the other end of resistor R55 is connected to the output pin 6 of the operational amplifier U27. Pin 4 of the operational amplifier U27 is connected to Vee and capacitor C77, one end of capacitor C77 is grounded. The signal that has successfully completed buffering and impedance matching is output to the analog-to-digital converter chip U10. The converted digital signal communicates with the microcontroller through the isolation transmission chip module. Specifically, combined with Figures 3-5 As shown, pin 6 of analog-to-digital converter chip U10 is connected to one end of capacitors C10 and C20. The other ends of capacitors C10 and C20 are connected to AGND and one end of capacitor C22. The other end of capacitor C22 is connected to pin 7 of analog-to-digital converter chip U10. Pins 2, 5, 8, 13, and 15 of analog-to-digital converter chip U10 are all connected to AGND. Pins 16 and 11 of analog-to-digital converter chip U10 are connected to a positive 5V power supply. The isolation transmission chip module includes a first isolation transmission chip U7 and a second isolation transmission chip U8. Pins 1 and 7 of the first isolation transmission chip U7 are connected to a negative 3.3V power supply VCC, and pins 16 and 10 are connected to a positive 5V power supply. Further, the filter capacitor module includes a first filter capacitor and a second filter capacitor, combined with... Figure 6 and Figure 7As shown, the first filter capacitor includes capacitors C119, C120, C121, and C122, which are connected in parallel. One end of the parallel connection is connected to the +5V power supply, and the other end is grounded (DGND). The second filter capacitor includes capacitors C81, C82, C99, and C98. Specifically, one end of capacitors C81, C82, and C99 is connected to Vcc, and the other end of capacitors C81, C82, and C99 is connected to one end of capacitor C98. The other end of capacitor C98 is connected to Vee. The power supply operating circuit module includes a first power supply operating circuit, a second power supply operating circuit, and a third power supply operating circuit, combined with... Figures 8-10As shown, the first power supply circuit includes a fixed-voltage three-terminal integrated regulator U11. The IN pin of the fixed-voltage three-terminal integrated regulator U11 is connected to Vcc, the OUT pin of the fixed-voltage three-terminal integrated regulator U11 is connected to a positive 5V power supply, and pin 2 of the fixed-voltage three-terminal integrated regulator U11 is grounded (DGND). The second power supply circuit includes a fixed-voltage three-terminal integrated regulator U19. Pin 3 of the fixed-voltage three-terminal integrated regulator U19 is connected to Vcc and one end of capacitor C31. Vcc is connected to one end of capacitor C32. The other ends of capacitors C32 and C31, along with one end of capacitors C30 and C29, are connected to pin 2 of the fixed-voltage three-terminal integrated regulator U19, where pin 2 is grounded. The other ends of capacitors C30 and C29 are connected to pin 1 of the fixed-voltage three-terminal integrated regulator U19 and Ctr1_LDO+5V.The third power supply circuit includes chip U26. Pin 1 of chip U26 is connected to capacitors C34 and C53, and the 24V power supply VCC. Chip U26 is an isolated DC-DC converter. The 24V power supply VCC is also connected to inductor L7 and capacitor C47. One end of inductor L7 is connected to the 24V power supply IN3 and capacitor C50. The 24V power supply IN3 is connected to capacitor C49. The other ends of capacitors C49 and C50 are grounded to GND3 and connected to inductor L11. The other end of inductor L11 is connected to... The other end of capacitor C47 is connected to PGND. The other end of capacitor C47 is also connected to capacitor C53, pin 2 of chip U26, capacitor C67, and one end of capacitor C75. The other end of capacitor C67 is connected to pin 3 of chip U26, inductor L13, and capacitor C61. The other end of capacitor C75 is connected to pin 4 of chip U26, capacitor C61, capacitor C39, and inductor L9. The other end of capacitor C39 is connected to inductor L5, pin 5 of chip U26, and capacitor C34. Inductor L5 is also connected to one end of capacitor C40. The capacitor C43 is connected to pin 1 of the voltage regulator chip U21. The other end of the capacitor C40 is connected to the other end of the inductor L9, one end of the capacitor C57, one end of the capacitor C43, one end of the capacitor C58, and pin 2 of the voltage regulator chip U21. The other end of the inductor L13 is connected to the capacitors C57 and C58 and pin 2 of the chip U29. Pin 1 of the chip U29 is connected to pin 2 of the voltage regulator chip U21. Pin 3 of the voltage regulator chip U21 is connected to one end of the sixteenth capacitor C35, the power supply Vcc, and pin 3 of the chip U23. This provides voltage regulation. Pin 2 of chip U21 is also connected to the other end of capacitor C35, the other end of capacitor C36, one end of capacitor C62, one end of capacitor C64, and pin 2 of chip U23. The other ends of capacitors C62 and C64 are connected to chip U29 and power supply Vee. Pin 2 of chip U23 is also connected to one end of capacitors C45, C55, and C70 and ground. The other ends of capacitors C45, C55, and C70 are connected to pin 1 of chip U23 and positive 5V power supply.

[0073] Combination Figure 11As shown, the preamplifier power supply monitoring circuit includes a first resistor R49, a second resistor R54, a first capacitor C108, a second capacitor C73, a 12V to 5V power chip U28, a first isolation amplifier U31, a third capacitor C74, and a fourth capacitor C109. One end of the first resistor R49 is connected to the 12V power output terminal OUT, the second capacitor C73, and the power chip U28. The other end of the first resistor R49 is connected to the second resistor R54, the first capacitor C108, and the first isolation amplifier U31. One end of the second resistor R54 and the first capacitor C108 are grounded together, and the first capacitor C108 is also connected to the first isolation amplifier U31. The third capacitor C74, the second capacitor C73, and the power chip U28 are grounded together. The power chip U28 is also connected to the third capacitor C74 and the first isolation amplifier U31. The first isolation amplifier U31 is connected to the fourth capacitor C109.

[0074] The preamplifier power supply monitoring circuit monitors the preamplifier power supply circuit, combined with... Figure 12 The preamplifier power supply circuit shown includes a power supply unit, a first filter capacitor unit, and a first power supply output interface. The power supply unit is connected to the first power supply output interface, the first filter capacitor unit is connected to the first power supply output interface, and the first filter capacitor unit is connected to the first power supply output interface. Specifically, the power supply unit includes a diode D1 whose anode is grounded to GND2, a diode D1 whose cathode is connected to the positive 12V input voltage IN2, a resistor R1, and the source of a PMOS transistor Q1. The gate of the PMOS transistor Q1 is connected to resistors R1 and R3. The drain of the PMOS transistor Q1 is connected to inductor L1 and capacitor C1. Inductor L1 is connected to capacitors C2 and C3, a resistor R2, and the output voltage +12VOUT. Capacitor C1 is connected to an optocoupler HPCL817, capacitors C2 and C3, a photodiode D3, and a diode D2. The photodiode D3 is connected to resistor R2, ground GND2, and the anode of diode D2. The cathode of diode D2 is connected to the output voltage +12VOUT and the first power supply output interface J5. The HPCL817 optocoupler is also connected to switch SW1 and resistor R3. Resistor R3 connects to resistor R1 and the gate of PMOS transistor Q1. The HPCL817 optocoupler is also connected to resistor R12 and the supply voltage VCC. Figure 13 The first filter capacitor unit shown includes filter capacitor C14 and filter capacitor C13, which are connected in parallel. One end of the parallel capacitors is grounded, and the other end is connected to the input power supply +12VIN2. It also includes a first power supply output interface J5, one end of which is connected to the output voltage +12VOUT, and the other end is grounded to GND2; its function is to serve as the output port of the preamplifier power supply circuit.

[0075] Combination Figure 14As shown, the power supply monitoring circuit of the acquisition card includes a third resistor R68, a fourth resistor R72, a fifth capacitor C127, a sixth capacitor C130, a second isolation amplifier U37, and a seventh capacitor C131. One end of the third resistor R68 is connected to the positive 5V power output terminal OUT, the fifth capacitor C127, and the second isolation amplifier U37. The other end of the third resistor R68 is connected to the fourth resistor R72, the sixth capacitor C130, and the second isolation amplifier U37. One end of the fifth capacitor C127 is grounded. One end of the sixth capacitor C130 is connected to the fourth resistor R72, grounded, and the second isolation amplifier U37. The second isolation amplifier U37 is connected to the seventh capacitor C131.

[0076] Combination Figure 15 As shown, the power supply monitoring circuit of the acquisition card is used to monitor the power supply control output circuit of the acquisition card. The power supply control output circuit includes a power supply output unit, a second filter capacitor unit, and a second power supply output interface. The power supply output unit is connected to the second power supply output interface, the second power supply output interface is connected to the second filter capacitor unit, and the second filter capacitor unit is connected to the power supply output unit. Specifically, the power supply output unit circuit consists of the source, drain, and gate corresponding to the S, D, and G pins of field-effect transistors U9 and U15. Both can be selected as IRF9310 field-effect transistors. The S pins of both field-effect transistors U9 and U15 are connected to one end of resistor R41, the negative terminal of diode D8, and the +5V voltage input terminal VIN1. The positive terminal of diode D8 is grounded to GND1. The gate (G) pins of MOSFETs U9 and U15 are connected to the other end of resistor R41, the optocoupler HCPL817, and pin 1 of switch SW5. Pin 2 of switch SW5 is connected to optocoupler HCPL817, capacitors C25 and C26, the negative terminal of photodiode D10, the positive terminal of diode D11, and ground GND1. Optocoupler HCPL817 is also connected to -3.3V VCC and resistor R43. One end of resistor R43 is connected to the microcontroller output pin U2_L35P_P, which is used to control the power supply output and shutdown. Switch SW5 is used to force the power supply output on; shorting pins 1 and 2 will force it on, while disconnecting pins 1 and 2 means it is controlled by the signal from optocoupler U25. Both MOSFETs U9 and U15 have their D pins connected to capacitors C25 and C26, resistor R35, the cathode of diode D11, and the +5V output voltage OUT. Resistor R35 is connected to the anode of photodiode D10. For example... Figure 16The second filter capacitor unit shown includes filter capacitors C42 and C41, both of which are filter capacitors for the +5V power input of the data acquisition card. Filter capacitors C42 and C41 are connected in parallel, with one end grounded and the other end connected to the input power supply +5VIN1. It also includes a second power output interface J8. Pin 2 of J8 is connected to the +5V output voltage, while pins 1 and 3 are grounded. Its function is to provide a power output interface for the data acquisition card.

[0077] Combination Figures 17-22 The circuit diagram shown primarily controls the high-voltage power supply switch circuit of the mass spectrometer, the power output enable circuit, and the power output polarity switching function. All four modules share the same output control function. Specifically, Figure 22 This is a +24V power supply control circuit for a high-voltage power supply. It includes a first control circuit unit, a second control circuit unit, and a third control circuit unit connected in parallel. The first control circuit unit includes capacitors C16 and C15 connected in parallel, with one end grounded and the other end connected to +24VIN3, resistor R6, the source of MOSFET Q2, and the drain of MOSFET Q2 connected to capacitor C5, inductor L2, capacitor C4, capacitor C6, resistor R7, and the cathode of diode D4. Diode D4's cathode is connected to the DC power supply, while its anode is grounded. The anode of diode D4 is also connected to the cathode of photodiode D5, capacitors C4, C6, and C5, and optocoupler U4. The anode of photodiode D5 is connected to resistor R7. Optocoupler U4 is also connected to resistor R10 and pins 1 and 2 of switch SW2. Resistor R10 is connected to pin 1 of switch SW2, the gate of MOSFET Q2, and resistor R6. Optocoupler U4 is also connected to resistor R15 and the collector of transistor Q3. The emitter of transistor Q3 is connected to VCC and resistor R4. R4 is connected to resistor R8, and resistor R8 is connected to the base of transistor Q3. The second and third control circuit units have identical structures. The second control circuit unit consists of capacitor C17, capacitor C18, resistor R19, MOSFET Q4, resistor R21, capacitor C8, inductor L3, capacitor C7, capacitor C9, resistor R20, diode D7, diode D6, switch SW3, resistor R15, and optocoupler U12. The third control circuit unit consists of capacitor C21, capacitor C19, resistor R36, MOSFET Q5, resistor R39, capacitor C27, inductor L4, capacitor C24, capacitor C28, resistor R37, diode D12, diode D9, switch SW4, resistor R42, and optocoupler U20. The connection method of these components is the same as that of the first control circuit unit. (Specific details can be found in the attached diagram.) Figure 22As shown, further details are omitted here; the output terminals connected to resistors R15, R25, and R42 in the circuit are all connected to the microcontroller's control pins, used to control the optocoupler's on / off state. For example... Figure 17 The first I / O output circuit shown is the high-voltage power supply 1 operating control output circuit; it includes a pin connector P1, where pin 1 of pin connector P1 is grounded, pin 2 is connected to the DC power supply DC, and pin 6 is connected to resistor R5 and optocoupler U2. Resistor R5 is connected to the DC power supply DC, and optocoupler U2 is grounded, connected to power supply VCC, and resistor R11. Resistor R11 is connected to the microcontroller output pin W2_L44P_P, which is used to control the switch of the externally connected power module. Figure 18 The second I / O output circuit shown is the high-voltage power supply 2 operating control output circuit; it includes a pin connector P3, where pin 1 of pin connector P3 is grounded, pin 2 is connected to the DC power supply DC, pin 6 is connected to resistor R23 and optocoupler U14, resistor R23 is connected to the DC power supply DC, optocoupler U2 is grounded, connected to power supply VCC and resistor R26, and resistor R11 is connected to the microcontroller output pin V3_IO_B2, which is used to control the switch of the externally connected power module. Figure 19 The diagram shows the pulse and +24V power supply interface outputs; including the pulse and power supply output interface J9, where pin 1 is grounded and pin 2 is connected to the DC power supply. (The diagram is incomplete and requires further context.) Figure 20 The third I / O output circuit shown is the high-voltage power supply 3 operating control output circuit; it includes a pin connector P2, where pin 1 of pin connector P2 is grounded, pin 2 is connected to the DC power supply DC, pin 6 is connected to resistor R9 and optocoupler U3, resistor R5 is connected to the DC power supply DC, optocoupler U2 is grounded, connected to power supply VCC and resistor R13, and resistor R13 is connected to the microcontroller output pin V2_L38P_P, which controls the switch of the externally connected power module. Figure 21 The fourth I / O output circuit shown is the high-voltage power supply 4 operating control output circuit; it includes a pin connector P4, where pin 1 is grounded, pin 2 is connected to the DC power supply, pin 7 is connected to resistor R29 and optocoupler U18, resistor R29 is connected to the DC power supply, optocoupler U18 is grounded, connected to the power supply VCC and resistor R34, resistor R34 is connected to the microcontroller output pin T4_IO_B2, controlling the module switch. Pin 6 of pin connector P4 is connected to resistor R22 and optocoupler U13, optocoupler U13 is grounded, connected to the power supply VCC and resistor R24, resistor R24 ​​is connected to the microcontroller output pin P6_IO_B2, controlling the module switch; resistor R22 is connected to the DC power supply. The working principle of the entire circuit is: when the vacuum level meets the opening condition, Figure 22 The circuit module shown starts working, for Figures 17-21The circuit module shown outputs +24V power. Figures 17-21 The circuit module shown is the control output interface between the pulse box and the high-voltage power supply. The vacuum activation condition is set to a vacuum level below 3 × 10⁻⁶. -4 Pa.

[0078] Combination Figures 23-24 The high-vacuum gauge vacuum acquisition circuit shown mainly includes a high-vacuum gauge power supply switch control circuit, a high-vacuum gauge comparator circuit, an eighth capacitor C72, and a high-vacuum gauge output interface. The comparison result signal is ultimately used to enable the high-voltage power supply output of the high-vacuum gauge comparator circuit. Specifically, in conjunction with... Figure 23 It is the eighth capacitor C72 of the +24V power supply. This eighth capacitor C72 is a filter capacitor. One end of it is grounded and the other end is connected to the power supply voltage +24VIN3. Figure 24 It is a high vacuum gauge comparison circuit, which compares the vacuum simulation signal of the high vacuum gauge with the set threshold. The control signal is ultimately output to the above-mentioned circuit. Figure 22 This indicates the +24V power supply control circuit of the high-voltage power supply; specifically, Figure 24 The high vacuum comparator circuit includes a first operational amplifier U6. Pin 2 of the first operational amplifier U6 is connected to the tenth acquisition channel AD10 of the 1:16 analog switch and one end of the ninth resistor R71. The other end of the ninth resistor R71 is connected to the base of the first transistor Q9. The emitter of the first transistor Q9 is grounded. The collector of the first transistor Q9 is connected to the tenth resistor R69. The tenth resistor R69 is connected to the second optocoupler U36. The second optocoupler U36 is connected to the emitter of the second transistor Q8. The collector of transistor Q8 is connected to the supply voltage +24VIN3. The base of the second transistor Q8 is connected to the eleventh resistor R64. The eleventh resistor R64 is connected to the twelfth resistor R61 and the output pin 6 of the first operational amplifier U6. The twelfth resistor R61 is connected to the thirteenth resistor R60, the pin 3 of the first operational amplifier U6, the fourteenth resistor R53, and the fourteenth capacitor C110. The fourteenth resistor R53 and the fourteenth capacitor C110 are both grounded. The thirteenth resistor R60 is connected to the reference voltage +10Verf. The working principle of this high vacuum gauge comparison circuit is as follows: based on the vacuum gauge output voltage and vacuum correspondence table provided by the high vacuum gauge manufacturer, the corresponding voltage value is calculated according to the designed vacuum requirements, such as according to the provided reference manual. This value is used as a reference point and compared with the actual vacuum value of the instrument. When the actual vacuum value is lower than the comparison threshold, the instrument can be turned on and operated normally; otherwise, the high vacuum gauge comparison circuit is forcibly shut down.

[0079] Figure 25 and Figure 26 These represent the high vacuum gauge power supply switch control circuit and the high vacuum gauge output interface, respectively, from which the real-time vacuum simulation signal is output. Figure 24The comparison circuit is shown. Specifically, the high vacuum gauge power supply switch control circuit includes a first optocoupler U35 and a first switch SW6. One end of the first optocoupler U35 is connected to a fifth resistor R62. The fifth resistor R62 is connected to an output pin Aal_IO_B2 of the microcontroller to output a signal. The first optocoupler U35 is also connected to pins 1 and 2 of the first switch SW6. Pin 2 of the first switch SW6 is also connected to a sixth resistor R50. The sixth resistor R50 is connected to a seventh resistor R47 and the gate and source of the first MOSFET. Connect the seventh resistor R47, the ninth capacitor C23, and the tenth capacitor C33. Connect the drain of the first MOSFET to the first inductor L15 and the eleventh capacitor C79. Connect the eleventh capacitor C79 to the twelfth capacitor C91 and the thirteenth capacitor C80. Connect the other pin 1 of the first switch SW6, the negative terminal of the first photodiode D16, and the first diode D15. Connect the first diode D15 to the eighth resistor R48, the thirteenth capacitor C80, the twelfth capacitor C91, and the first inductor L15. The eighth resistor R48 is connected to the positive terminal of the first photodiode D16.

[0080] Combination Figure 27 This is a circuit diagram for a high vacuum gauge comparison threshold reference circuit. Figure 24 Part of the circuit includes diode D17, whose pin 1 is connected to one end of resistor R57 and one end of resistor R65. The other end of resistor R65 is connected to pin 2 of diode D17 and capacitor C118. Capacitor C118 is connected to capacitor C128 and Ctrl_+10Vref. One end of capacitor C118 and capacitor C128 are connected to AGND. Pin 3 of diode D17 is connected to resistor R56 and resistor R57. One end of resistor R56 is connected to positive 24VIN3.

[0081] Combination Figures 28-33 The circuit shown is a low-vacuum gauge vacuum acquisition circuit, which includes a low-vacuum gauge power supply switch control circuit, a low-vacuum gauge output interface, a shorting resistor, a reference generation circuit, and a low-vacuum gauge comparison circuit. The low-vacuum gauge power supply switch control circuit powers the low-vacuum gauge vacuum acquisition circuit, outputting a signal from the low-vacuum gauge output interface to the FPGA system control board interface. The vacuum value is then fed back sequentially from the low-vacuum gauge output interface to the reference generation circuit and the low-vacuum gauge comparison circuit. The comparison result signal is ultimately used to enable the power supply switch output of the pre-stage baffle valve. Details are as follows:

[0082] Figure 28The diagram shows the low-vacuum gauge power supply switch control circuit. Specifically, it includes a third optocoupler U44, one end of which is connected to the fifteenth resistor R82. The fifteenth resistor R82 is connected to the microcontroller pin output signal V4_IO_B2, and the other end is connected to the power supply VCC. The third optocoupler U44 is also connected to pins 1 and 2 of the second switch SW7. Pin 2 of the second switch SW7 is also connected to the sixteenth resistor R79. The sixteenth resistor R79 is connected to the seventeenth resistor R76 and the gate of the second MOSFET. The source of the second MOSFET is connected to the seventeenth resistor R76 and +24VIN3. The seventeenth resistor R76 is connected to the negative terminal of the second diode D20 and the parallel-connected fifteenth capacitor C37 and sixteenth capacitor C35. The other ends of the parallel-connected fifteenth capacitor C37 and sixteenth capacitor C35 are grounded together, and the positive terminal of the second diode D20 is grounded. The drain of the second MOSFET is connected to the second inductor L20, the seventeenth capacitor C143, the seventeenth capacitor C143 is connected to the eighteenth capacitor C144, the nineteenth capacitor C139, pin 1 of the second switch SW7, the negative terminal of the second photodiode D23, and the third diode D22. The third diode D22 is connected to the eighteenth resistor R77, the nineteenth capacitor C139, the eighteenth capacitor C144, and the second inductor L20. The eighteenth resistor R77 is connected to the positive terminal of the second photodiode D23. Figure 29 This shows the output interface of the low vacuum gauge; Figure 30 The image shows capacitor C68, which is a filter capacitor with an input of +24V. Figure 31 The figure shows the shorting resistor R52 between analog ground and power ground; Figure 32 This indicates a +10V reference generation circuit, which outputs a +10V reference voltage to... Figure 33 In the circuit shown, specifically, pin 1 of the reference voltage chip D14 is connected to resistors R45 and R46. Resistor R45 is connected to resistor R44 and pin 3 of the reference voltage chip D14. Resistor R44 is connected to +24VIN3. Pin 3 of the reference voltage chip D14 is also connected to the reference voltage, capacitor C71, and capacitor C69. One end of capacitor C71 and capacitor C69 is grounded together, and capacitor C69 is connected to pin 2 of the reference voltage chip D14.

[0083] Combination Figure 33 The low-vacuum gauge comparison circuit shown is a circuit that compares the vacuum analog signal of the low-vacuum gauge with a set threshold, providing a comparison reference for the circuit. The real-time vacuum signal of the low-vacuum gauge is provided by... Figure 29The circuit interface inputs are shown below. Specifically, it includes a second operational amplifier U24. The inverting input of the second operational amplifier U24 is connected to the nineteenth resistor R33, which is connected to the 9th acquisition channel AD9 of the 1:16 analog switch and the twentieth resistor R51. The non-inverting input of the second operational amplifier U24 is connected to the twenty-first resistor R28, the twenty-second resistor R38, and the output pin 6 of the second operational amplifier U24. The twenty-first resistor R28 is connected to the reference voltage and the twenty-third resistor R31, which is connected to the twenty-fourth resistor R30, which is grounded. The output pin 6 of the second operational amplifier U24 is connected to the twenty-fifth resistor R32, which is connected to the base of transistor Q13. The collector of transistor Q13 is connected to...

[0084] +24VIN3, the emitter of transistor Q13 is connected to the fourth optocoupler U22, which is also connected to the twenty-eighth resistor R17. The twenty-eighth resistor R17 is connected to the collector of the third transistor Q7, whose emitter is grounded. The base of the third transistor Q7 is connected to the twentieth resistor R51. The fourth optocoupler U22 is also connected to the twenty-sixth resistor R14, the collector of the fourth transistor Q11, and the collector of the fifth transistor Q12. The emitter of the fifth transistor Q12 is grounded, and its base is connected to the twenty-seventh resistor R40, which is connected to the microcontroller pin output signal N5_IO_B2. The base of the fourth transistor Q11 is connected to the twenty-ninth resistor R18, which is connected to the microcontroller pin output signal T5_IO_B2. The working principle of this low vacuum gauge comparison circuit is as follows: based on the vacuum gauge output voltage and vacuum correspondence table provided by the low vacuum gauge manufacturer, the corresponding voltage value is calculated according to the designed vacuum requirements. This value is used as a reference point and compared with the actual vacuum value of the instrument. When the actual vacuum value is lower than the comparison threshold, the instrument can be turned on and started normally, opening the vacuum baffle valve to start the molecular pump; otherwise, the molecular pump is turned off to protect the molecular pump.

[0085] Combination Figures 28-33 ,Will Figure 29 The interface shown outputs to the low vacuum gauge comparator circuit, which then... Figure 29 The interface shown feeds back the vacuum value. Figure 33 The circuit shown is Figure 32 The generated reference is compared to produce a control signal for the next module, and the remaining modules are filter capacitors.

[0086] In this embodiment, the PC mass spectrometer needs to operate in a high vacuum environment. To maintain this environment, the instrument employs a combination of a forepump and a molecular pump. The forepump provides a suitable working pressure for the molecular pump, which maintains the high vacuum environment. The molecular pump operates under conditions where the outlet vacuum level needs to be below 100 Pa. The low-vacuum gauge vacuum acquisition circuit monitors whether the molecular pump's operating conditions are met. If not, the molecular pump must be shut down to prevent damage. During normal spectrum acquisition, the PC mass spectrometer operates at a high voltage of 20 kV. The high-vacuum gauge vacuum acquisition circuit is used to prevent power discharge. This circuit monitors the instrument's vacuum environment in real time. If the vacuum environment is damaged for any reason, this module immediately shuts off the high-voltage power supply, protecting the power supply, the instrument, and personnel.

[0087] Combination Figures 34-36 The diagram shows the communication circuit between the FPGA-controlled RS232 serial port module and the PC, as well as the temperature reading circuit for the two temperature sensors in the instrument system. Specifically, Figure 34 It is the RS232 serial port module of the FPGA main controller communicating with the PC. Figure 35 and Figure 36 The circuit shown is the temperature reading circuit for the two temperature sensors in the instrument system. Both have identical internal circuitry, and their signals ultimately communicate with the main control chip, the FPGA. Figure 35 The circuit includes a temperature sensor interface T1. Pin 3 of T1 is connected to resistors R66 and R74. Resistor R66 is connected to pin 1 of the thermocouple analog-to-digital converter U30, and both are grounded. Resistor R74 is connected to capacitors C85 and C89 and pin 2 of the thermocouple analog-to-digital converter U30. Capacitor C89 is connected to resistors R81 and C92 and pin 3 of the thermocouple analog-to-digital converter U30. Capacitor C92 is grounded. Resistor R81 is connected to resistor R86 and pin 1 of the temperature sensor interface T1. Resistor R86 is connected to pin 4 of the thermocouple analog-to-digital converter U30, and both are connected to the power supply VCC. Power supply VCC is connected to capacitor C88, which is grounded. Pins 5, 6, and 7 of the thermocouple analog-to-digital converter U30 are connected to the SPI transmission bus of the temperature chip.

[0088] Combination Figures 34-36 The principle of signal transmission in the entire circuit shown is as follows: Figure 34 This shows serial communication, which is communication between a microcontroller and a PC. Figure 35 and Figure 36 The circuit shown is a temperature acquisition module that digitizes the temperature and transmits it to the microcontroller. Figure 34 The circuit shown is transmitted to the computer software.

[0089] Combination Figure 37 and Figure 38The 3.3V power supply generation circuit that constitutes the main control FPGA, specifically, Figure 37 It is the power supply input port of the FPGA system control board; Figure 38 This is the 3.3V power supply generation circuit for the main control FPGA; pins 3 and 6 of the switching power supply U16 are grounded, and pin 1 is connected to a capacitor assembly, which includes capacitors C56, C54, C52, C51, and C59. One end of the capacitor assembly is grounded, and the other end is connected to the 5V input network name, i.e., +5VIN. Among them, capacitors C56, C54, C52, C51, and C59 are connected in parallel. Pin 2 of the switching power supply U16 is connected to the negative terminal of the fourth diode D13 and the third inductor L6. The positive terminal of the fourth diode D13 is grounded. The third inductor L6 is connected to pin 4 of the switching power supply U16, the twentieth capacitor C44, the twenty-first capacitor C46, ​​the twenty-second capacitor C48, and the power supply VCC. The twenty-second capacitor C48 is connected to the twenty-first capacitor C46, ​​the twentieth capacitor C44, ground, and pin 5 of the switching power supply U16.

[0090] In this embodiment, the signal is transmitted to the microcontroller and then distributed to each module, and the modules are relatively independent of each other.

[0091] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A control circuit for a time-of-flight mass spectrometer, characterized in that, It includes a power supply system, an FPGA system control board, a DAC control board, an ADC control board, and an I / O output control circuit. The FPGA system control board is equipped with an FPGA main control circuit, the DAC control board is equipped with a DAC control circuit, and the ADC control board is equipped with an ADC control circuit. The power supply system provides power to the DAC control circuit, the ADC control circuit, the I / O output control circuit, and the FPGA main control circuit. The DAC control circuit, ADC control circuit, and I / O output control circuit are set up independently in pairs, and the DAC control circuit, ADC control circuit, and I / O output control circuit exchange data with the FPGA main control circuit respectively; the FPGA main control circuit is also connected to a PC mass spectrometer; the I / O output control circuit is connected to the power amplifier tube through an optocoupler, and the power amplifier tube is connected to voltage output circuits with different voltage values. The output circuit of the ADC control board is connected to the high vacuum gauge vacuum acquisition circuit, the low vacuum gauge vacuum acquisition circuit, the acquisition card power supply monitoring circuit, and the preamplifier power supply monitoring circuit, respectively. The high vacuum gauge vacuum acquisition circuit includes a high vacuum gauge power supply switch control circuit, a high vacuum gauge comparison circuit, an eighth capacitor, and a high vacuum gauge output interface. The high vacuum gauge power supply switch control circuit outputs the real-time vacuum simulation signal to the high vacuum gauge comparison circuit through the high vacuum gauge output interface. The high vacuum gauge power supply switch control circuit includes a first optocoupler and a first switch. One end of the first optocoupler is connected to a fifth resistor, which is connected to an output pin of the microcontroller to output a signal. The first optocoupler is also connected to the first switch. One pin of the first switch is also connected to a sixth resistor. The sixth resistor is connected to a seventh resistor and the gate of a first MOSFET. The source of the first MOSFET is connected to the seventh resistor, a ninth capacitor, and a tenth capacitor. The drain of the first MOSFET is connected to a first inductor and an eleventh capacitor. The eleventh capacitor is connected to a twelfth capacitor, a thirteenth capacitor, another pin of the first switch, the negative terminal of a first photodiode, and a first diode. The first diode is connected to an eighth resistor, a thirteenth capacitor, a twelfth capacitor, and a first inductor. The eighth resistor is connected to the positive terminal of the first photodiode.

2. The time-of-flight mass spectrometer control circuit according to claim 1, characterized in that, The ADC control circuit includes an analog switch, an impedance matching module, an analog-to-digital converter chip, an isolation transmission chip module, a filter capacitor module, and a power supply circuit. After the signal is processed by the analog switch, it is output to the impedance matching module, and then to the analog-to-digital converter chip. The converted digital signal communicates with the microcontroller through the isolation transmission chip module.

3. The time-of-flight mass spectrometer control circuit according to claim 2, characterized in that, The preamplifier power supply monitoring circuit includes a first resistor, a second resistor, a first capacitor, a second capacitor, a power chip, a first isolation amplifier, a third capacitor, and a fourth capacitor. One end of the first resistor is connected to the power output terminal, the second capacitor, and the power chip, and the other end of the first resistor is connected to the second resistor, the first capacitor, and the first isolation amplifier. One end of the second resistor and the first capacitor are grounded together, and the first capacitor is also connected to the first isolation amplifier. The third capacitor, the second capacitor, and the power chip are grounded together, and the power chip is also connected to the third capacitor and the first isolation amplifier. The first isolation amplifier is connected to the fourth capacitor.

4. The time-of-flight mass spectrometer control circuit according to claim 3, characterized in that, The preamplifier power supply monitoring module monitors the preamplifier power supply circuit, which includes a power supply unit, a first filter capacitor unit, and a first power supply output interface. The power supply unit is connected to the first power supply output interface, the power supply unit is connected to the first filter capacitor unit, and the first filter capacitor unit is connected to the first power supply output interface.

5. A time-of-flight mass spectrometer control circuit according to claim 2, characterized in that, The power supply monitoring circuit of the acquisition card includes a third resistor, a fourth resistor, a fifth capacitor, a sixth capacitor, a second isolation amplifier, and a seventh capacitor. One end of the third resistor is connected to the power supply, the fifth capacitor, and the second isolation amplifier, and the other end of the third resistor is connected to the fourth resistor, the sixth capacitor, and the second isolation amplifier. One end of the fifth capacitor is grounded, and one end of the sixth capacitor is connected to the fourth resistor, grounded, and the second isolation amplifier. The second isolation amplifier is connected to the seventh capacitor.

6. The time-of-flight mass spectrometer control circuit according to claim 5, characterized in that, The power supply monitoring circuit of the acquisition card monitors the power supply control output circuit of the acquisition card. The power supply control output circuit of the acquisition card includes a power supply output unit, a second filter capacitor unit, and a second power supply output interface. The power supply output unit is connected to the second power supply output interface, the second power supply output interface is connected to the second filter capacitor unit, and the second filter capacitor unit is connected to the power supply output unit.

7. The time-of-flight mass spectrometer control circuit according to claim 1, characterized in that, The I / O output control circuit consists of a first I / O output circuit, a second I / O output circuit, a third I / O output circuit, and a fourth I / O output circuit.

8. The time-of-flight mass spectrometer control circuit according to claim 1, characterized in that, The high vacuum gauge comparator circuit includes a first operational amplifier, wherein the first operational amplifier is connected to one end of a ninth resistor, the other end of the ninth resistor is connected to the base of a first transistor, the emitter of the first transistor is grounded, the collector of the first transistor is connected to a tenth resistor, the tenth resistor is connected to a second optocoupler, the second optocoupler is connected to the emitter of a second transistor, the collector of the second transistor is connected to a power supply, the base of the second transistor is connected to an eleventh resistor, the eleventh resistor is connected to a twelfth resistor and the output pin of the first operational amplifier, the twelfth resistor is connected to a thirteenth resistor, the first operational amplifier, a fourteenth resistor and a fourteenth capacitor, wherein the fourteenth resistor and the fourteenth capacitor are both grounded, and the thirteenth resistor is connected to a reference voltage.

9. The time-of-flight mass spectrometer control circuit according to claim 1, characterized in that, The low vacuum gauge vacuum acquisition circuit includes a low vacuum gauge power supply switch control circuit, a low vacuum gauge output interface, a shorting resistor, a reference generation circuit, and a low vacuum gauge comparison circuit. The low vacuum gauge power supply switch control circuit is activated to supply power to the low vacuum gauge vacuum acquisition circuit, and the signal is output from the low vacuum gauge output interface to the interface of the FPGA system control board. Then, the vacuum value is fed back to the reference generation circuit and the low vacuum gauge comparison circuit in sequence from the low vacuum gauge output interface.

10. A time-of-flight mass spectrometer control circuit according to claim 9, characterized in that, The low-vacuum gauge power supply switch control circuit includes a third optocoupler. One end of the third optocoupler is connected to the fifteenth resistor, which is connected to an output pin of the microcontroller to output a signal. The third optocoupler is also connected to a second switch, and one pin of the second switch is connected to the sixteenth resistor. The sixteenth resistor is connected to the seventeenth resistor and the gate of the second MOSFET. The source of the second MOSFET is connected to the seventeenth resistor. The seventeenth resistor is connected to the cathode of the second diode, the fifteenth capacitor, and the sixteenth capacitor. The other ends of the fifteenth and sixteenth capacitors connected in parallel are grounded together. The anode of the second diode is grounded. The drain of the second MOSFET is connected to the second inductor and the seventeenth capacitor. The seventeenth capacitor is connected to the eighteenth capacitor, the nineteenth capacitor, the second switch, the cathode of the second photodiode, and the third diode. The third diode is connected to the eighteenth resistor, the nineteenth capacitor, the eighteenth capacitor, and the second inductor. The eighteenth resistor is connected to the anode of the second photodiode.

11. A time-of-flight mass spectrometer control circuit according to claim 9, characterized in that, The low-vacuum gauge comparator circuit includes a second operational amplifier. The inverting input of the second operational amplifier is connected to the nineteenth resistor, which is connected to the twentieth resistor. The non-inverting input of the second operational amplifier is connected to the twenty-first and twenty-second resistors, as well as the second operational amplifier itself. The twenty-first resistor is connected to a reference voltage and the twenty-third resistor, which is connected to the twenty-fourth resistor, which is grounded. The second operational amplifier is connected to the twenty-fifth resistor, which is connected to the base of transistor Q13. The collector of transistor Q13 is connected to the power supply, and the emitter of transistor Q13 is connected to a fourth optical... The fourth optocoupler is also connected to the twenty-eighth resistor, which is connected to the collector of the third transistor. The emitter of the third transistor is grounded, and the base of the third transistor is connected to the twentieth resistor. The fourth optocoupler is also connected to the twenty-sixth resistor, the collector of the fourth transistor, and the collector of the fifth transistor. The emitter of the fifth transistor is grounded, and the base of the fifth transistor is connected to the twenty-seventh resistor. The twenty-seventh resistor is connected to an output pin of the microcontroller to output a signal. The base of the fourth transistor is connected to the twenty-ninth resistor, which is connected to an output pin of the microcontroller to output a signal.

12. The time-of-flight mass spectrometer control circuit according to claim 1, characterized in that, The FPGA main control circuit includes a power generation circuit and a power input port. The power input port supplies power to the power generation circuit. The power generation circuit includes a switching power supply. The switching power supply is connected to a capacitor assembly, the negative terminal of the fourth diode, and the third inductor. The positive terminal of the fourth diode is grounded. The third inductor is connected to the switching power supply, the twentieth capacitor, the twenty-first capacitor, the twenty-second capacitor, and the power supply VCC. The twenty-second capacitor is connected to the twenty-first capacitor, the twenty-first capacitor, ground, and the switching power supply.

13. The time-of-flight mass spectrometer control circuit according to claim 1, characterized in that, The DAC control electrical components are arranged in parallel, and the parallel-arranged digital-to-analog converters operate independently.

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