Light source driving circuit for atomic spectrum analysis and driving method thereof

Abstract

The invention discloses a light source driving circuit for atomic spectrum analysis and a driving method thereof. The light source driving circuit comprises a deuterium lamp driving circuit and a cathode lamp driving circuit, the deuterium lamp driving circuit comprises a first main control circuit, a first rectification circuit, a first energy storage circuit, a first voltage division circuit, a first feedback circuit, a first constant current driving circuit, a first voltage reduction circuit, a first voltage switching circuit, a third voltage reduction circuit and a heating circuit. According to the light source driving circuit for atomic spectrum analysis and the driving method thereof, the deuterium lamp and the cathode lamp share one set of light path and acquisition circuit, so that the structure and the circuit are greatly simplified; meanwhile, control is easy, a light cutting wheel is not needed to obtain modulated pulse signals, the service life is prolonged, and use and maintenance are better facilitated.

Description

Technical Field

[0001] The present invention belongs to the technical field of drive circuits and relates to a light source drive circuit, and in particular to a light source drive circuit for atomic spectrum analysis and a drive method thereof. Background Art

[0002] The atomic absorption spectrophotometer uses the Lambert-Beer law, that is, the absorption intensity of the target atom to a specific wavelength of light is quantitatively analyzed to obtain the concentration of the atom in the sample. The measurement light source used for atomic absorption is divided into a sharp line light source and a continuous light source. The hollow cathode lamp used in the present invention belongs to a sharp line light source. The driving circuit needs to apply a high voltage of 300 to 500V between the cathode and the anode. The wavelength of the excitation light after excitation is strictly equal to the absorption wavelength of the cathode element. The driving scheme uses a constant current, and the stability of the lamp current is conducive to maintaining a stable radiation intensity.

[0003] Since the absorption obtained by the light beam measurement is the sum of the measured atomic absorption and the background absorption, the light measurement link needs to be compensated. Most of the existing spectrophotometers on the market are equipped with compensation solutions, which are mainly divided into deuterium lamp type, Zeeman type, and continuous light source type. The advantage of deuterium lamp background correction is that it has little effect on measurement sensitivity. Traditional deuterium lamps are constant current continuous light sources. Therefore, when sharing the same optical path with cathode lamps, a light-cutting wheel is required for mechanical modulation. During collection, an external synchronization signal provided by the light-cutting wheel is required to distinguish between measurement and compensation; or a dual optical path compensation method is used, using reflectors, lenses and other means for spectral compensation, and two sets of detection components for collection. The disadvantages of the above two solutions are the complex optical path design and strict structural accuracy requirements. Complex systems will increase the cost of the whole machine and maintenance.

[0004] In view of this, there is an urgent need to design a new light source driving circuit so as to overcome at least part of the above-mentioned defects of the existing light source driving circuit. Summary of the invention

[0005] The present invention provides a light source driving circuit for atomic spectrum analysis and a driving method thereof, which can simplify the structure and circuit, and at the same time can prolong the service life, and is more conducive to use and maintenance.

[0006] To solve the above technical problem, according to one aspect of the present invention, the following technical solution is adopted:

[0007] A light source driving circuit for atomic spectrum analysis, the light source driving circuit comprising a deuterium lamp driving circuit and a cathode lamp driving circuit;

[0008] The deuterium lamp driving circuit includes a first main control circuit, a first rectifier circuit, a first energy storage circuit, a first voltage divider circuit, a first feedback circuit, a first constant current driving circuit, a first step-down circuit, a first voltage switching circuit, a third step-down circuit and a heating circuit;

[0009] The first rectifier circuit, the first energy storage circuit, and the first voltage divider circuit are connected in sequence, the first main control circuit is respectively connected to the first step-down circuit, the first voltage switching circuit, and the first constant current drive circuit, the first constant current drive circuit is connected to the first feedback circuit, and the first voltage switching circuit and the third step-down circuit are respectively connected to the heating circuit;

[0010] The first voltage divider circuit is used to connect the anode of the deuterium lamp, the first feedback circuit is used to connect the cathode of the deuterium lamp, and the heating circuit is used to connect the cathode and the heating electrode of the deuterium lamp respectively.

[0011] As an implementation mode of the present invention, the cathode lamp driving circuit includes a second main control circuit, a second transformer, a second rectifier circuit, a second energy storage circuit, a second feedback circuit, a second constant current driving circuit and a second step-down circuit;

[0012] The second rectifier circuit is connected to the second energy storage circuit, and the second step-down circuit, the second main control circuit, the second constant current drive circuit, and the second feedback circuit are connected in sequence; the second energy storage circuit is used to connect the anode of the cathode lamp, and the second feedback circuit is used to connect the cathode of the cathode lamp.

[0013] As an implementation mode of the present invention, the deuterium lamp driving circuit and the cathode lamp driving circuit share a rectifier circuit and an energy storage circuit.

[0014] As an embodiment of the present invention, the light source driving circuit includes a main control circuit and a pulse driving circuit. The main control circuit is connected to the pulse driving circuit, and the pulse driving circuit is used to control the time division multiplexing of the deuterium lamp and the cathode lamp.

[0015] As an implementation mode of the present invention, the first constant current driving circuit includes a first operational amplifier U1, a second operational amplifier U2, a third operational amplifier U3, a first MOS tube Q1, a second MOS tube M2, a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a first zero resistor R10, and a first first resistor R11;

[0016] The non-inverting input terminal of the first operational amplifier U1 is respectively connected to the second end of the first resistor R1 and the first end of the first capacitor C1, and the second end of the first capacitor C1 is grounded; the first end of the first resistor R1 is connected to the main control circuit; the inverting input terminal of the first operational amplifier U1 is respectively connected to the output terminal of the first operational amplifier U1 and the first end of the second resistor R2;

[0017] The second end of the second resistor R2 is respectively connected to the first end of the fifth resistor R5 and the drain of the first MOS transistor M1; the gate of the first MOS transistor M1 is connected to the second end of the third resistor R3, the first end of the third resistor R3 is respectively connected to the main control circuit and the first end of the fourth resistor R4, and the second end of the fourth resistor R4 is connected to the power supply voltage; the source of the first MOS transistor M1 is grounded;

[0018] The second end of the fifth resistor R5 is connected to the non-inverting input end of the second operational amplifier U2, and the inverting input end of the second operational amplifier U2 is respectively connected to the second end of the sixth resistor R6 and the first end of the seventh resistor R7; the first end of the sixth resistor R6 is grounded; the output end of the second operational amplifier U2 is respectively connected to the second end of the seventh resistor R7 and the first end of the eighth resistor R8;

[0019] The non-inverting input terminal of the third operational amplifier U3 is connected to the second end of the eighth resistor R8, and the inverting input terminal of the third operational amplifier U3 is respectively connected to the first end of the ninth resistor R9 and the first end of the first zero resistor R10; the output terminal of the third operational amplifier U3 is respectively connected to the first end of the first resistor R11 and the second end of the second capacitor C2; the first end of the second capacitor C2 is connected to the second end of the ninth resistor R9;

[0020] The second end of the first zero resistor R10 is connected to the first feedback circuit and the source of the second MOS transistor M2 respectively; the gate of the second MOS transistor M2 is connected to the second end of the first resistor R11, and the drain of the second MOS transistor M2 is connected to the first voltage divider circuit.

[0021] As an implementation mode of the present invention, the first voltage divider circuit includes a first second resistor R12, a first third resistor R13, and a first fourth resistor R14; the first end of the first second resistor R12 is connected to the first end of the first energy storage circuit, the second end of the first second resistor R12 is connected to the second end of the first third resistor R13, the first end of the first third resistor R13 is connected to the first end of the first fourth resistor R14, and the second end of the first fourth resistor R14 is connected to the drain of the second MOS tube M2;

[0022] The first feedback circuit includes a first fifth resistor R15, a first sixth resistor R16, a first seventh resistor R17, a first eighth resistor R18, and a first ninth resistor R19;

[0023] The first end of the first-fifth resistor R15, the first end of the first-sixth resistor R16, the first end of the first-seventh resistor R17, the first end of the first-eighth resistor R18, and the first end of the first-nineth resistor R19 are respectively connected to the emitter of the second MOS tube M2;

[0024] The second end of the first-fifth resistor R15, the second end of the first-sixth resistor R16, the second end of the first-seventh resistor R17, the second end of the first-eighth resistor R18, and the second end of the first-nineth resistor R19 are grounded respectively.

[0025] As an implementation mode of the present invention, the second constant current driving circuit includes a fourth operational amplifier U4, a fifth operational amplifier U5, a sixth operational amplifier U6, a third MOS tube M3, a fourth MOS tube M4, a fourth capacitor C4, a fifth capacitor C5, a second first resistor R21, a second second resistor R22, a second third resistor R23, a second fourth resistor R24, a second fifth resistor R25, a second sixth resistor R26, a second seventh resistor R27, a second eighth resistor R28, a second ninth resistor R29, a third zero resistor R30, and a third first resistor R31;

[0026] The non-inverting input terminal of the fourth operational amplifier U4 is respectively connected to the second end of the second-first resistor R21 and the first end of the fourth capacitor C4, and the second end of the fourth capacitor C4 is grounded; the first end of the second-first resistor R21 is connected to the main control circuit; the inverting input terminal of the fourth operational amplifier U4 is respectively connected to the output terminal of the fourth operational amplifier U4 and the first end of the second-second resistor R22;

[0027] The second end of the second-second resistor R22 is respectively connected to the first end of the second-fifth resistor R25 and the drain of the third MOS tube M3; the gate of the third MOS tube M3 is respectively connected to the second end of the second-third resistor R23 and the first end of the second-fourth resistor R24, the first end of the second-third resistor R23 is connected to the main control circuit, and the second end of the second-fourth resistor R24 ​​is connected to the power supply voltage; the source of the third MOS tube M3 is grounded;

[0028] The second end of the second-fifth resistor R25 is connected to the non-inverting input end of the fifth operational amplifier U5, and the inverting input end of the fifth operational amplifier U5 is respectively connected to the second end of the second-sixth resistor R26 and the first end of the second-seventh resistor R27; the first end of the second-sixth resistor R26 is grounded; the output end of the fifth operational amplifier U5 is respectively connected to the second end of the second-seventh resistor R27 and the first end of the second-eighth resistor R28;

[0029] The non-inverting input terminal of the sixth operational amplifier U6 is connected to the second end of the second eighth resistor R28, and the inverting input terminal of the sixth operational amplifier U6 is respectively connected to the first end of the second ninth resistor R29 and the first end of the third zero resistor R30; the output terminal of the sixth operational amplifier U6 is respectively connected to the first end of the third first resistor R31 and the second end of the fifth capacitor C5; the first end of the fifth capacitor C5 is connected to the second end of the second ninth resistor R29;

[0030] The second end of the third zero resistor R30 is connected to the second feedback circuit and the source of the fourth MOS tube M4 respectively; the gate of the fourth MOS tube M4 is connected to the second end of the third first resistor R31, and the drain of the fourth MOS tube M4 is connected to the second voltage divider circuit.

[0031] As an implementation manner of the present invention, the second voltage divider circuit includes a third resistor R32 and a third resistor R33; a first end of the third resistor R32 is connected to a first end of the second energy storage circuit, a second end of the third resistor R32 is connected to a first end of the third resistor R33, and a second end of the third resistor R33 is connected to a drain of the fourth MOS tube M4;

[0032] The second feedback circuit includes a third-fourth resistor R34 and a third-fifth resistor R35; the source of the fourth MOS tube M4 is respectively connected to the first end of the third-fourth resistor R34 and the first end of the third-fifth resistor R35, and the second end of the third-fourth resistor R34 and the second end of the third-fifth resistor R35 are respectively grounded.

[0033] As an embodiment of the present invention, the light source driving circuit further includes a heating power supply control circuit and a heating mode switching circuit, and the heating power supply control circuit is connected to the heating mode switching circuit;

[0034] The heating power supply control circuit includes a seventh chip U7; the heating mode switching circuit includes a fifth MOS tube M5, a sixth MOS tube M6, a first inductor L1, a fifth diode D5, a seventh capacitor C7, an eighth capacitor C8, a thirty-sixth resistor R36, a thirty-seventh resistor R37, a thirty-eighth resistor R38 and a thirty-ninth resistor R39;

[0035] The gate of the fifth MOS transistor M5 is connected to the seventh chip U7, and the drain of the fifth MOS transistor M5 is connected to the seventh chip U7; the source of the fifth MOS transistor M5 is respectively connected to the drain of the sixth MOS transistor M6, the first end of the first inductor L1, and the cathode of the fifth diode D5;

[0036] The gate of the sixth MOS transistor M6 is connected to the seventh chip U7, the source of the sixth MOS transistor M6 is grounded, and the anode of the fifth diode D5 is grounded;

[0037] The second end of the first inductor L1 is respectively connected to the first end of the seventh capacitor C7, the first end of the third resistor R36, the first end of the third resistor R37, and the first end of the third resistor R38; the second end of the seventh capacitor C7 is grounded;

[0038] The second end of the 36th resistor R36 is connected to the first end of the 8th capacitor C8, the second end of the 8th capacitor C8 is respectively connected to the second end of the 37th resistor R37 and the first end of the 39th resistor R39, the second end of the 38th resistor R38 is connected to the first end of the 39th resistor R39 through a switch; the second end of the 39th resistor R39 is grounded.

[0039] According to another aspect of the present invention, the following technical solution is adopted: a driving method of the above-mentioned light source driving circuit, the driving method comprising: the main control circuit controls the time division multiplexing of the deuterium lamp and the cathode lamp through the pulse driving circuit control.

[0040] The beneficial effects of the present invention are as follows: in the light source driving circuit and driving method of the atomic spectral analysis proposed by the present invention, the deuterium lamp and the cathode lamp share a set of optical paths and acquisition circuits, which greatly simplifies the structure and circuit; at the same time, the present invention is simple to control and does not require the use of a light cutting wheel to obtain a modulated pulse signal, thereby increasing the service life and being more conducive to use and maintenance.

[0041] In one use scenario of the present invention, time-staggered high-voltage constant-current pulses are used to drive the cathode lamp and the deuterium lamp respectively, and measurement and compensation can be completed with only one set of optical paths and detection components. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 The figure is a schematic diagram of the composition of a deuterium lamp driving circuit in a light source driving circuit in one embodiment of the present invention.

[0043] Figure 2 The figure is a schematic diagram of the composition of a cathode lamp driving circuit in a light source driving circuit in one embodiment of the present invention.

[0044] Figure 3 FIG. 4 is a circuit diagram of a deuterium lamp driving circuit in one embodiment of the present invention.

[0045] Figure 4 FIG. 4 is a circuit diagram of a cathode lamp driving circuit in an embodiment of the present invention.

[0046] Figure 5 Schematic diagram of a heating power control circuit and a heating mode switching circuit in one embodiment of the present invention.

[0047] Figure 6 FIG. 4 is a circuit diagram of a rectifier circuit and an energy storage circuit in one embodiment of the present invention. DETAILED DESCRIPTION

[0048] The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0049] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0050] The description in this section is only for several typical embodiments, and the present invention is not limited to the scope of the embodiments. The same or similar prior art means and some technical features in the embodiments are mutually replaced within the scope of the present invention.

[0051] The description of the steps in each embodiment in the specification is only for the convenience of explanation, and the implementation method of the present application is not limited by the order of implementation of the steps.

[0052] The term "connection" as used in the specification includes both direct connection and indirect connection, such as connection through some active devices, passive devices or electrically conductive media; it may also include connection through other active devices or passive devices known to those skilled in the art on the basis of achieving the same or similar functional purposes, such as connection through circuits or components such as switches and follower circuits.

[0053] The present invention discloses a light source driving circuit for atomic spectrum analysis, the light source driving circuit comprising a deuterium lamp driving circuit and a cathode lamp driving circuit. The light source driving circuit can be a light source driving circuit for atomic spectrum analysis; of course, it can also be other light source driving circuits.

[0054] Figure 1 FIG. 1 is a schematic diagram of the composition of a deuterium lamp driving circuit in a light source driving circuit in an embodiment of the present invention; please refer to FIG. Figure 1 The deuterium lamp driving circuit includes a first main control circuit 10, a first rectifier circuit 11, a first energy storage circuit 12, a first voltage divider circuit 13, a first feedback circuit 14, a first constant current driving circuit 15, a first voltage reduction circuit 16, a first voltage switching circuit 17, a third voltage reduction circuit 18 and a heating circuit 19. The first rectifier circuit 11, the first energy storage circuit 12 and the first voltage divider circuit 13 are connected in sequence, the first main control circuit 10 is respectively connected to the first voltage reduction circuit 16, the first voltage switching circuit 17 and the first constant current driving circuit 15, the first constant current driving circuit 15 is connected to the first feedback circuit 14, the first voltage switching circuit 17 and the third voltage reduction circuit 18 are respectively connected to the heating circuit 19. The first voltage divider circuit 13 is used to connect the anode of the deuterium lamp, the first feedback circuit 14 is used to connect the cathode of the deuterium lamp, and the heating circuit 19 is used to connect the cathode and the heating electrode of the deuterium lamp respectively.

[0055] Figure 2 FIG. 1 is a schematic diagram showing the composition of a cathode lamp driving circuit in a light source driving circuit in an embodiment of the present invention; please refer to FIG. Figure 2In one embodiment of the present invention, the cathode lamp driving circuit includes a second main control circuit 20, a second transformer 21, a second rectifier circuit 22, a second energy storage circuit 23, a second feedback circuit 24, a second constant current driving circuit 25 and a second step-down circuit 26. The second rectifier circuit 22 is connected to the second energy storage circuit 23, and the second step-down circuit 26, the second main control circuit 20, the second constant current driving circuit 25 and the second feedback circuit 24 are connected in sequence; the second energy storage circuit 23 is used to connect the anode of the cathode lamp, and the second feedback circuit 24 is used to connect the cathode of the cathode lamp.

[0056] In one embodiment of the present invention, the deuterium lamp driving circuit and the cathode lamp driving circuit may share a rectifier circuit and an energy storage circuit. Figure 6 is a circuit diagram of a rectifier circuit and an energy storage circuit in one embodiment of the present invention; please refer to Figure 6 The rectifier circuit includes a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4, which form a rectifier bridge. The energy storage circuit includes a ninth capacitor C9 and a first zero capacitor C10, which are connected in parallel. In addition, the deuterium lamp and the cathode lamp can also share an optical path and a collection circuit.

[0057] The light source driving circuit may include a main control circuit and a pulse driving circuit. The main control circuit is connected to the pulse driving circuit, and the pulse driving circuit is used to control the time division multiplexing of the deuterium lamp and the cathode lamp.

[0058] In one usage scenario of the present invention, time division multiplexing is actually active modulation on the light source side; for example, the deuterium lamp is turned on for 5ms and off for 5ms, and the cathode lamp is turned on for 5ms and off for 5ms, which is one cycle. Then the detection end passively receives the light signal and converts it into a voltage signal.

[0059] The use of deuterium lamps is divided into three stages: filament preheating, ignition and operation. Preheating is to make the hot electrons emitted by the cathode of the deuterium lamp filament accelerate the hot electrons to move to the anode during the ignition stage, and achieve inelastic collision with deuterium gas molecules to excite, thereby radiating a continuous spectrum of deuterium molecules. In order to ensure accurate measurement compensation, the luminous intensity of the deuterium lamp needs to be stable. Therefore, after the deuterium lamp is ignited and enters the normal working state, it is driven by a constant current pulse, and a small current is required to keep the cathode warm to maintain the excited state. Therefore, the drive circuit is divided into two parts, one is the heating and power switching circuit, and the other is the high-voltage excitation and constant current drive circuit. The cathode lamp uses a constant current pulse drive circuit, and the lighting time can be staggered with the deuterium lamp, and the rectification and energy storage circuit are shared with the deuterium lamp.

[0060] Figure 3 is a circuit diagram of a deuterium lamp driving circuit in one embodiment of the present invention; please refer to Figure 3 In one embodiment of the present invention, the first constant current driving circuit includes a first operational amplifier U1, a second operational amplifier U2, a third operational amplifier U3, a first MOS tube Q1, a second MOS tube M2, a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a first zero resistor R10, and a first one resistor R11. In addition, as Figure 3 As shown, the first constant current driving circuit can also include a third capacitor C3.

[0061] The non-inverting input terminal of the first operational amplifier U1 is respectively connected to the second end of the first resistor R1 and the first end of the first capacitor C1, and the second end of the first capacitor C1 is grounded; the first end of the first resistor R1 is connected to the main control circuit; the inverting input terminal of the first operational amplifier U1 is respectively connected to the output terminal of the first operational amplifier U1 and the first end of the second resistor R2.

[0062] The second end of the second resistor R2 is respectively connected to the first end of the fifth resistor R5 and the drain of the first MOS tube M1; the gate of the first MOS tube M1 is connected to the second end of the third resistor R3, the first end of the third resistor R3 is respectively connected to the main control circuit and the first end of the fourth resistor R4, and the second end of the fourth resistor R4 is connected to the power supply voltage; the source of the first MOS tube M1 is grounded.

[0063] The second end of the fifth resistor R5 is connected to the non-inverting input end of the second operational amplifier U2, and the inverting input end of the second operational amplifier U2 is respectively connected to the second end of the sixth resistor R6 and the first end of the seventh resistor R7; the first end of the sixth resistor R6 is grounded; the output end of the second operational amplifier U2 is respectively connected to the second end of the seventh resistor R7 and the first end of the eighth resistor R8.

[0064] The non-inverting input terminal of the third operational amplifier U3 is connected to the second end of the eighth resistor R8, and the inverting input terminal of the third operational amplifier U3 is respectively connected to the first end of the ninth resistor R9 and the first end of the first zero resistor R10; the output terminal of the third operational amplifier U3 is respectively connected to the first end of the first resistor R11 and the second end of the second capacitor C2; the first end of the second capacitor C2 is connected to the second end of the ninth resistor R9.

[0065] The second end of the first zero resistor R10 is connected to the first feedback circuit and the source of the second MOS transistor M2 respectively; the gate of the second MOS transistor M2 is connected to the second end of the first resistor R11, and the drain of the second MOS transistor M2 is connected to the first voltage divider circuit.

[0066] The first voltage divider circuit may include a first second resistor R12, a first third resistor R13, and a first fourth resistor R14; the first end of the first second resistor R12 is connected to the first end of the first energy storage circuit, the second end of the first second resistor R12 is connected to the second end of the first third resistor R13, the first end of the first third resistor R13 is connected to the first end of the first fourth resistor R14, and the second end of the first fourth resistor R14 is connected to the drain of the second MOS tube M2.

[0067] The first feedback circuit may include a first fifth resistor R15, a first sixth resistor R16, a first seventh resistor R17, a first eighth resistor R18, and a first ninth resistor R19. The first end of the first fifth resistor R15, the first end of the first sixth resistor R16, the first end of the first seventh resistor R17, the first end of the first eighth resistor R18, and the first end of the first ninth resistor R19 are respectively connected to the emitter of the second MOS tube M2. The second end of the first fifth resistor R15, the second end of the first sixth resistor R16, the second end of the first seventh resistor R17, the second end of the first eighth resistor R18, and the second end of the first ninth resistor R19 are respectively grounded.

[0068] Figure 4 is a circuit diagram of a cathode lamp driving circuit in one embodiment of the present invention; please refer to Figure 4 In one embodiment of the present invention, the second constant current driving circuit includes a fourth operational amplifier U4, a fifth operational amplifier U5, a sixth operational amplifier U6, a third MOS tube M3, a fourth MOS tube M4, a fourth capacitor C4, a fifth capacitor C5, a second first resistor R21, a second second resistor R22, a second third resistor R23, a second fourth resistor R24, a second fifth resistor R25, a second sixth resistor R26, a second seventh resistor R27, a second eighth resistor R28, a second ninth resistor R29, a third zero resistor R30, and a third first resistor R31. In addition, as Figure 4 As shown, the second constant current drive circuit can also include a sixth capacitor C6.

[0069] The non-inverting input terminal of the fourth operational amplifier U4 is respectively connected to the second end of the second-first resistor R21 and the first end of the fourth capacitor C4, and the second end of the fourth capacitor C4 is grounded; the first end of the second-first resistor R21 is connected to the main control circuit; the inverting input terminal of the fourth operational amplifier U4 is respectively connected to the output terminal of the fourth operational amplifier U4 and the first end of the second-second resistor R22.

[0070] The second end of the second-second resistor R22 is respectively connected to the first end of the second-fifth resistor R25 and the drain of the third MOS tube M3; the gate of the third MOS tube M3 is respectively connected to the second end of the second-third resistor R23 and the first end of the second-fourth resistor R24, the first end of the second-third resistor R23 is connected to the main control circuit, and the second end of the second-fourth resistor R24 ​​is connected to the power supply voltage; the source of the third MOS tube M3 is grounded.

[0071] The second end of the second-fifth resistor R25 is connected to the non-inverting input end of the fifth operational amplifier U5, and the inverting input end of the fifth operational amplifier U5 is respectively connected to the second end of the second-sixth resistor R26 and the first end of the second-seventh resistor R27; the first end of the second-sixth resistor R26 is grounded; the output end of the fifth operational amplifier U5 is respectively connected to the second end of the second-seventh resistor R27 and the first end of the second-eighth resistor R28.

[0072] The non-inverting input terminal of the sixth operational amplifier U6 is connected to the second end of the second eighth resistor R28, and the inverting input terminal of the sixth operational amplifier U6 is respectively connected to the first end of the second ninth resistor R29 and the first end of the third zero resistor R30; the output terminal of the sixth operational amplifier U6 is respectively connected to the first end of the third first resistor R31 and the second end of the fifth capacitor C5; the first end of the fifth capacitor C5 is connected to the second end of the second ninth resistor R29.

[0073] The second end of the third zero resistor R30 is connected to the second feedback circuit and the source of the fourth MOS tube M4 respectively; the gate of the fourth MOS tube M4 is connected to the second end of the third first resistor R31, and the drain of the fourth MOS tube M4 is connected to the second voltage divider circuit.

[0074] The second voltage divider circuit may include a third resistor R32 and a third resistor R33; a first end of the third resistor R32 is connected to a first end of the second energy storage circuit, a second end of the third resistor R32 is connected to a first end of the third resistor R33, and a second end of the third resistor R33 is connected to a drain of the fourth MOS tube M4;

[0075] The second feedback circuit may include a third-fourth resistor R34 and a third-fifth resistor R35; the source of the fourth MOS tube M4 is respectively connected to the first end of the third-fourth resistor R34 and the first end of the third-fifth resistor R35, and the second end of the third-fourth resistor R34 and the second end of the third-fifth resistor R35 are respectively grounded.

[0076] The light source driving circuit further includes a heating power supply control circuit and a heating mode switching circuit, and the heating power supply control circuit is connected to the heating mode switching circuit. Figure 5 is a circuit diagram of a heating power control circuit and a heating mode switching circuit in one embodiment of the present invention; please refer to Figure 5 In one embodiment of the present invention, the heating power supply control circuit includes a seventh chip U7; the heating mode switching circuit includes a fifth MOS tube M5, a sixth MOS tube M6, a first inductor L1, a fifth diode D5, a seventh capacitor C7, an eighth capacitor C8, a thirty-sixth resistor R36, a thirty-seventh resistor R37, a thirty-eighth resistor R38 and a thirty-ninth resistor R39.

[0077] The gate of the fifth MOS tube M5 is connected to the seventh chip U7, and the drain of the fifth MOS tube M5 is connected to the seventh chip U7; the source of the fifth MOS tube M5 is respectively connected to the drain of the sixth MOS tube M6, the first end of the first inductor L1, and the cathode of the fifth diode D5. The gate of the sixth MOS tube M6 is connected to the seventh chip U7, the source of the sixth MOS tube M6 is grounded, and the anode of the fifth diode D5 is grounded. The second end of the first inductor L1 is respectively connected to the first end of the seventh capacitor C7, the first end of the third six resistor R36, the first end of the third seven resistor R37, and the first end of the third eight resistor R38; the second end of the seventh capacitor C7 is grounded. The second end of the third six resistor R36 is connected to the first end of the eighth capacitor C8, the second end of the eighth capacitor C8 is respectively connected to the second end of the third seven resistor R37 and the first end of the third nine resistor R39, and the second end of the third eight resistor R38 is connected to the first end of the third nine resistor R39 through a switch; the second end of the third nine resistor R39 is grounded.

[0078] The present invention further discloses a driving method for the light source driving circuit, the driving method comprising: a main control circuit controls the time division multiplexing of the deuterium lamp and the cathode lamp through a pulse driving circuit.

[0079] In one use scenario of the present invention, the use of a deuterium lamp is divided into three stages: filament preheating, ignition, and operation. Preheating is to make the hot electrons emitted by the cathode of the deuterium lamp filament accelerate the hot electrons to move to the anode during the ignition stage, and to achieve inelastic collisions with deuterium gas molecules and excite, thereby radiating a continuous spectrum of deuterium molecules. In order to ensure accurate measurement compensation, the luminous intensity of the deuterium lamp needs to be stable. Therefore, after the deuterium lamp is ignited and enters a normal working state, it is driven by a constant current pulse, and a small current is required to keep the cathode warm to maintain the excited state. Therefore, the drive circuit is divided into two parts, one is the heating and power switching circuit, and the other is the high-voltage excitation and constant current drive circuit. The cathode lamp uses a constant current pulse drive circuit, and the lighting time can be staggered with the deuterium lamp, and the rectification and energy storage circuit are shared with the deuterium lamp.

[0080] In summary, the light source driving circuit and driving method for atomic spectroscopy analysis proposed in the present invention, the deuterium lamp and the cathode lamp share a set of optical paths and acquisition circuits, which greatly simplifies the structure and circuit; at the same time, the present invention is simple to control, and does not require the use of a light-cutting wheel to obtain a modulated pulse signal, thereby increasing the service life and being more convenient for use and maintenance. In one use scenario of the present invention, time-staggered high-voltage constant-current pulses are used to drive the cathode lamp and the deuterium lamp respectively, and measurement and compensation can be completed with only one set of optical paths and detection components.

[0081] It should be noted that the present application can be implemented in software and / or a combination of software and hardware; for example, it can be implemented using an application-specific integrated circuit (ASIC), a general-purpose computer, or any other similar hardware device. In some embodiments, the software program of the present application can be executed by a processor to implement the above steps or functions. Similarly, the software program of the present application (including related data structures) can be stored in a computer-readable recording medium; for example, a RAM memory, a magnetic or optical drive or a floppy disk and the like. In addition, some steps or functions of the present application can be implemented in hardware; for example, as a circuit that cooperates with a processor to perform various steps or functions.

[0082] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0083] The description and application of the present invention here are illustrative, and it is not intended to limit the scope of the present invention to the above-mentioned embodiments. The effects or advantages involved in the embodiments may not be embodied in the embodiments due to interference from various factors, and the description of the effects or advantages is not used to limit the embodiments. The deformation and change of the embodiments disclosed here are possible, and the replacement of the embodiments and the various equivalent parts are well known to those of ordinary skill in the art. It should be clear to those skilled in the art that the present invention can be implemented in other forms, structures, arrangements, proportions, and with other components, materials and parts without departing from the spirit or essential features of the present invention. Other deformations and changes can be made to the embodiments disclosed here without departing from the scope and spirit of the present invention.

Claims

1. A light source driving circuit for atomic spectroscopy analysis, characterized in that: The light source driving circuit includes a deuterium lamp driving circuit and a cathode lamp driving circuit; The deuterium lamp driving circuit includes a first main control circuit, a first rectifier circuit, a first energy storage circuit, a first voltage divider circuit, a first feedback circuit, a first constant current driving circuit, a first step-down circuit, a first voltage switching circuit, a third step-down circuit and a heating circuit; The first rectifier circuit, the first energy storage circuit, and the first voltage divider circuit are connected in sequence, the first main control circuit is respectively connected to the first step-down circuit, the first voltage switching circuit, and the first constant current drive circuit, the first constant current drive circuit is connected to the first feedback circuit, and the first voltage switching circuit and the third step-down circuit are respectively connected to the heating circuit; The first voltage divider circuit is used to connect the anode of the deuterium lamp, the first feedback circuit is used to connect the cathode of the deuterium lamp, and the heating circuit is used to connect the cathode and the heating electrode of the deuterium lamp respectively.

2. The light source driving circuit for atomic spectrum analysis according to claim 1, characterized in that: The cathode lamp driving circuit includes a second main control circuit, a second transformer, a second rectifier circuit, a second energy storage circuit, a second feedback circuit, a second constant current driving circuit and a second step-down circuit; The second rectifier circuit is connected to the second energy storage circuit, and the second step-down circuit, the second main control circuit, the second constant current drive circuit, and the second feedback circuit are connected in sequence; the second energy storage circuit is used to connect the anode of the cathode lamp, and the second feedback circuit is used to connect the cathode of the cathode lamp.

3. The light source driving circuit for atomic spectrum analysis according to claim 1, characterized in that: The deuterium lamp driving circuit and the cathode lamp driving circuit share a rectifier circuit and an energy storage circuit.

4. The light source driving circuit for atomic spectrum analysis according to claim 1, characterized in that: The light source driving circuit comprises a main control circuit and a pulse driving circuit. The main control circuit is connected to the pulse driving circuit, and the pulse driving circuit is used to control the time division multiplexing of the deuterium lamp and the cathode lamp.

5. The light source driving circuit for atomic spectrum analysis according to claim 1, characterized in that: The first constant current driving circuit includes a first operational amplifier U1, a second operational amplifier U2, a third operational amplifier U3, a first MOS tube Q1, a second MOS tube M2, a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a first zero resistor R10, and a first first resistor R11; The non-inverting input terminal of the first operational amplifier U1 is respectively connected to the second end of the first resistor R1 and the first end of the first capacitor C1, and the second end of the first capacitor C1 is grounded; the first end of the first resistor R1 is connected to the main control circuit; the inverting input terminal of the first operational amplifier U1 is respectively connected to the output terminal of the first operational amplifier U1 and the first end of the second resistor R2; The second end of the second resistor R2 is respectively connected to the first end of the fifth resistor R5 and the drain of the first MOS transistor M1; the gate of the first MOS transistor M1 is connected to the second end of the third resistor R3, the first end of the third resistor R3 is respectively connected to the main control circuit and the first end of the fourth resistor R4, and the second end of the fourth resistor R4 is connected to the power supply voltage; the source of the first MOS transistor M1 is grounded; The second end of the fifth resistor R5 is connected to the non-inverting input end of the second operational amplifier U2, and the inverting input end of the second operational amplifier U2 is respectively connected to the second end of the sixth resistor R6 and the first end of the seventh resistor R7; the first end of the sixth resistor R6 is grounded; the output end of the second operational amplifier U2 is respectively connected to the second end of the seventh resistor R7 and the first end of the eighth resistor R8; The non-inverting input terminal of the third operational amplifier U3 is connected to the second end of the eighth resistor R8, and the inverting input terminal of the third operational amplifier U3 is respectively connected to the first end of the ninth resistor R9 and the first end of the first zero resistor R10; the output terminal of the third operational amplifier U3 is respectively connected to the first end of the first resistor R11 and the second end of the second capacitor C2; the first end of the second capacitor C2 is connected to the second end of the ninth resistor R9; The second end of the first zero resistor R10 is connected to the first feedback circuit and the source of the second MOS transistor M2 respectively; the gate of the second MOS transistor M2 is connected to the second end of the first resistor R11, and the drain of the second MOS transistor M2 is connected to the first voltage divider circuit.

6. The light source driving circuit for atomic spectrum analysis according to claim 5, characterized in that: The first voltage divider circuit includes a first second resistor R12, a first third resistor R13, and a first fourth resistor R14; the first end of the first second resistor R12 is connected to the first end of the first energy storage circuit, the second end of the first second resistor R12 is connected to the second end of the first third resistor R13, the first end of the first third resistor R13 is connected to the first end of the first fourth resistor R14, and the second end of the first fourth resistor R14 is connected to the drain of the second MOS tube M2; The first feedback circuit includes a first fifth resistor R15, a first sixth resistor R16, a first seventh resistor R17, a first eighth resistor R18, and a first ninth resistor R19; The first end of the first-fifth resistor R15, the first end of the first-sixth resistor R16, the first end of the first-seventh resistor R17, the first end of the first-eighth resistor R18, and the first end of the first-nineth resistor R19 are respectively connected to the emitter of the second MOS tube M2; The second end of the first-fifth resistor R15, the second end of the first-sixth resistor R16, the second end of the first-seventh resistor R17, the second end of the first-eighth resistor R18, and the second end of the first-nineth resistor R19 are grounded respectively.

7. The light source driving circuit for atomic spectrum analysis according to claim 2, characterized in that: The second constant current driving circuit includes a fourth operational amplifier U4, a fifth operational amplifier U5, a sixth operational amplifier U6, a third MOS tube M3, a fourth MOS tube M4, a fourth capacitor C4, a fifth capacitor C5, a second first resistor R21, a second second resistor R22, a second third resistor R23, a second fourth resistor R24, a second fifth resistor R25, a second sixth resistor R26, a second seventh resistor R27, a second eighth resistor R28, a second ninth resistor R29, a third zero resistor R30, and a third first resistor R31; The non-inverting input terminal of the fourth operational amplifier U4 is respectively connected to the second end of the second-first resistor R21 and the first end of the fourth capacitor C4, and the second end of the fourth capacitor C4 is grounded; the first end of the second-first resistor R21 is connected to the main control circuit; the inverting input terminal of the fourth operational amplifier U4 is respectively connected to the output terminal of the fourth operational amplifier U4 and the first end of the second-second resistor R22; The second end of the second-second resistor R22 is respectively connected to the first end of the second-fifth resistor R25 and the drain of the third MOS tube M3; the gate of the third MOS tube M3 is respectively connected to the second end of the second-third resistor R23 and the first end of the second-fourth resistor R24, the first end of the second-third resistor R23 is connected to the main control circuit, and the second end of the second-fourth resistor R24 ​​is connected to the power supply voltage; the source of the third MOS tube M3 is grounded; The second end of the second-fifth resistor R25 is connected to the non-inverting input end of the fifth operational amplifier U5, and the inverting input end of the fifth operational amplifier U5 is respectively connected to the second end of the second-sixth resistor R26 and the first end of the second-seventh resistor R27; the first end of the second-sixth resistor R26 is grounded; the output end of the fifth operational amplifier U5 is respectively connected to the second end of the second-seventh resistor R27 and the first end of the second-eighth resistor R28; The non-inverting input terminal of the sixth operational amplifier U6 is connected to the second end of the second eighth resistor R28, and the inverting input terminal of the sixth operational amplifier U6 is respectively connected to the first end of the second ninth resistor R29 and the first end of the third zero resistor R30; the output terminal of the sixth operational amplifier U6 is respectively connected to the first end of the third first resistor R31 and the second end of the fifth capacitor C5; the first end of the fifth capacitor C5 is connected to the second end of the second ninth resistor R29; The second end of the third zero resistor R30 is connected to the second feedback circuit and the source of the fourth MOS tube M4 respectively; the gate of the fourth MOS tube M4 is connected to the second end of the third first resistor R31, and the drain of the fourth MOS tube M4 is connected to the second voltage divider circuit.

8. The light source driving circuit for atomic spectrum analysis according to claim 7, characterized in that: The second voltage divider circuit includes a third resistor R32 and a third resistor R33; a first end of the third resistor R32 is connected to a first end of the second energy storage circuit, a second end of the third resistor R32 is connected to a first end of the third resistor R33, and a second end of the third resistor R33 is connected to a drain of the fourth MOS tube M4; The second feedback circuit includes a third-fourth resistor R34 and a third-fifth resistor R35; the source of the fourth MOS tube M4 is respectively connected to the first end of the third-fourth resistor R34 and the first end of the third-fifth resistor R35, and the second end of the third-fourth resistor R34 and the second end of the third-fifth resistor R35 are respectively grounded.

9. The light source driving circuit for atomic spectrum analysis according to claim 1, characterized in that: The light source driving circuit further includes a heating power supply control circuit and a heating mode switching circuit, wherein the heating power supply control circuit is connected to the heating mode switching circuit; The heating power supply control circuit includes a seventh chip U7; the heating mode switching circuit includes a fifth MOS tube M5, a sixth MOS tube M6, a first inductor L1, a fifth diode D5, a seventh capacitor C7, an eighth capacitor C8, a thirty-sixth resistor R36, a thirty-seventh resistor R37, a thirty-eighth resistor R38 and a thirty-ninth resistor R39; The gate of the fifth MOS transistor M5 is connected to the seventh chip U7, and the drain of the fifth MOS transistor M5 is connected to the seventh chip U7; the source of the fifth MOS transistor M5 is respectively connected to the drain of the sixth MOS transistor M6, the first end of the first inductor L1, and the cathode of the fifth diode D5; The gate of the sixth MOS transistor M6 is connected to the seventh chip U7, the source of the sixth MOS transistor M6 is grounded, and the anode of the fifth diode D5 is grounded; The second end of the first inductor L1 is respectively connected to the first end of the seventh capacitor C7, the first end of the third resistor R36, the first end of the third resistor R37, and the first end of the third resistor R38; the second end of the seventh capacitor C7 is grounded; The second end of the 36th resistor R36 is connected to the first end of the 8th capacitor C8, the second end of the 8th capacitor C8 is respectively connected to the second end of the 37th resistor R37 and the first end of the 39th resistor R39, the second end of the 38th resistor R38 is connected to the first end of the 39th resistor R39 through a switch; the second end of the 39th resistor R39 is grounded.

10. A driving method for the light source driving circuit according to any one of claims 1 to 9, characterized in that: The driving method comprises: a main control circuit controls the time division multiplexing of the deuterium lamp and the cathode lamp through a pulse driving circuit.

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