A voltage regulating circuit for a cell analyzer

Abstract

This application discloses a voltage regulation circuit for a cell analyzer. The voltage regulation circuit includes: a first switching transistor connected to a voltage source via its emitter and connected to a voltage regulation circuit via its base and collector; and a voltage regulation circuit for regulating the base current of the first switching transistor, converting a first voltage provided by the voltage source into a second voltage, which is then output through the collector of the first switching transistor. Thus, by using a first switching transistor in the voltage regulation circuit to regulate the input first voltage, voltage division using resistors is unnecessary, achieving full-range voltage regulation and low power consumption.

Description

Technical Field

[0001] This application relates to the field of voltage regulation technology, and more particularly to a voltage regulating circuit for a cell analyzer. Background Technology

[0002] As a core component of flow cytometers, the avalanche photodiode (APD) plays an important role in the detection of lateral and fluorescence signals due to its advantages such as high sensitivity, fast response and miniaturization. To make the gain of the APD controllable, a controllable DC bias high voltage, typically between tens and hundreds of volts, needs to be applied across its terminals.

[0003] Currently, a DC-DC converter is generally used to boost a lower DC voltage to a higher voltage. The output of the DC / DC converter is then adjusted by a program to control the APD gain to achieve the desired level. If adjusting the gain of multiple APD channels is required, multiple DC / DC converters are needed, resulting in a complex design. Alternatively, a single DC / DC converter can be used, with its output high voltage set at a fixed value, typically greater than the APD's maximum breakdown voltage. A voltage regulation circuit is then built in the subsequent stage, using a DAC to control the APD's bias high voltage to adjust the gain. However, the voltage regulation circuit usually uses voltage divider resistors for adjustment. Due to the voltage drop and power consumption of the resistors themselves, the setting of the voltage divider resistors is limited, preventing the output voltage of the voltage regulation circuit from covering the full range. Furthermore, setting the resistance of the voltage divider resistors too small results in high power consumption. Utility Model Content

[0004] In view of this, embodiments of this application provide at least one voltage regulation circuit for a cell analyzer, which adjusts the input first voltage by setting a first switching transistor in the voltage regulation circuit, without the need for voltage division using resistors, and can achieve full-range voltage regulation and low power consumption.

[0005] The technical solution of this application embodiment is implemented as follows:

[0006] This application provides a voltage regulating circuit for a cell analyzer, the voltage regulating circuit including:

[0007] The first switching transistor is connected to a voltage source through its emitter and to a voltage regulation circuit through its base and collector. The voltage regulation circuit is used to adjust the base current of the first switching transistor and convert the first voltage provided by the voltage source into a second voltage, which is then output through the collector of the first switching transistor.

[0008] In the above embodiments, the voltage regulation circuit further includes a first filter circuit; the first filter circuit is connected to the collector of the first switching transistor.

[0009] In some embodiments, the voltage regulating circuit further includes a first resistor; the first resistor is disposed at the base of the first switching transistor; the first resistor is a high-resistance resistor.

[0010] In some embodiments, the voltage regulation circuit includes: a voltage setter, an error amplifier, a second switch, a second resistor, a first loop compensation capacitor, and a negative feedback circuit; the voltage setter is connected to the non-inverting input of the error amplifier; the second switch is connected to the output of the error amplifier through its base, grounded through its emitter via the second resistor, and connected to the first switch through its collector; the negative feedback circuit is connected to the collector of the first switch and the inverting input of the error amplifier, respectively; the first loop compensation capacitor is connected in parallel to the non-inverting input and output of the error amplifier.

[0011] In some embodiments, the first switching transistor is a positive-negative-positive bipolar junction transistor.

[0012] In some embodiments, the voltage regulation circuit further includes: a second filter circuit; the second filter circuit is disposed between the voltage setter and the non-inverting input of the error amplifier.

[0013] In some embodiments, there is a linear relationship between the voltage set by the voltage setter and the second voltage.

[0014] In some embodiments, the negative feedback circuit includes: a third resistor, a fourth resistor, a fifth resistor, and a second loop compensation capacitor; one end of the third resistor is connected to the first filter circuit and the second loop compensation capacitor respectively, and the other end is connected to one end of the fourth resistor; the other end of the fourth resistor is connected to the second loop compensation capacitor; one end of the fifth resistor is grounded, and the other end is connected to the inverting input terminal of the error amplifier, the first loop compensation capacitor, the fourth resistor, and the second loop compensation capacitor.

[0015] In some embodiments, a sixth resistor is provided at the base of the second switching transistor.

[0016] In some embodiments, the error amplifier is of the zero-drift type.

[0017] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and are not intended to limit the technical solutions of this application. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with this application and, together with the specification, serve to explain the technical solutions of this application.

[0019] Figure 1 This is a schematic diagram of an exemplary regulating circuit provided by related technologies;

[0020] Figure 2 This is a schematic diagram of an exemplary voltage regulation circuit for a cell analyzer provided in an embodiment of this application. Figure 1 ;

[0021] Figure 3 This is a schematic diagram of an exemplary voltage regulation circuit for a cell analyzer provided in an embodiment of this application. Figure 2 ;

[0022] Figure 4 This is a schematic diagram of an exemplary voltage regulation circuit for a cell analyzer provided in an embodiment of this application. Figure 3 ;

[0023] Figure 5 This is a schematic diagram of an exemplary voltage regulation circuit for a cell analyzer provided in an embodiment of this application. Figure 4 ;

[0024] Figure 6 This is a schematic diagram of an exemplary voltage regulation circuit for a cell analyzer provided in an embodiment of this application. Figure 5 ;

[0025] Figure 7 This is a schematic diagram illustrating an exemplary filtering result provided in an embodiment of this application;

[0026] Figure 8 This is an exemplary circuit stability test diagram provided in an embodiment of this application;

[0027] Figure 9 This is a schematic diagram of an exemplary voltage regulation circuit for a cell analyzer provided in an embodiment of this application. Figure 6 ;

[0028] Figure 10 This is a schematic diagram illustrating an exemplary input-output relationship provided in an embodiment of this application;

[0029] Figure 11 This is a schematic diagram of an exemplary voltage regulation circuit for a cell analyzer provided in an embodiment of this application. Figure 7 . Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application are further described in detail below with reference to the accompanying drawings and embodiments. The described embodiments should not be regarded as limitations on this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0032] The terms “first / second / third” are used merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that “first / second / third” may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terminology used herein is for descriptive purposes only and is not intended to be limiting of this application.

[0034] Flow cytometry is an instrument used for the rapid analysis of cell or particle characteristics, and is widely used in biological, medical research, and clinical diagnostics. Its core principle is to illuminate cells or particles in a sample with a laser and detect the scattered light and fluorescence signals to obtain information such as cell size, morphology, and surface markers.

[0035] An avalanche photodiode (APD) is a photoelectric sensor that converts light signals into current signals. This current signal can be converted into a voltage signal via a transimpedance circuit or a current-to-voltage converter. As a core component of flow cytometers, the APD plays a crucial role in the detection of lateral and fluorescence signals due to its high sensitivity, fast response, and miniaturization. To make the gain of an APD controllable, a controllable DC bias voltage, typically between tens and hundreds of volts, needs to be applied across its terminals.

[0036] There are generally two common approaches to multi-channel gain adjustment circuits: The first approach uses a DC / DC converter to boost a lower DC voltage to a higher voltage. Low-noise, high-voltage modules suitable for APD bias are readily available on the market. Then, a programmable digital-to-analog converter (DAC) is used to adjust the output of the DC / DC converter, controlling the APD gain to the desired level. If adjusting the gain of multiple channels' APDs is required, multiple DC / DC converters are needed. While this approach is conceptually simple, the overall circuitry is complex and the overall cost is too high. The second approach uses a single DC / DC converter with a fixed output high voltage, typically greater than the APD's maximum breakdown voltage. A voltage regulation circuit is then built into the subsequent stage, and the DAC controls the APD's bias high voltage to adjust the gain. In this approach, if adjusting the gain of multiple channels' APDs is required, only one DC / DC converter and multiple voltage regulation circuits are needed. This approach also meets the requirements, significantly reducing the cost of multi-channel circuits.

[0037] For example, such as Figure 1 As shown, a schematic diagram of an exemplary regulating circuit is illustrated. Figure 1 As shown, the regulating circuit 10 includes a voltage source 101, a voltage setter 102, resistor 1 (103), capacitor 1 (104), an error amplifier 105, resistor 2 (106), resistor 3 (107), resistor 4 (108), resistor 5 (109), a switching transistor 110, capacitor 2 (111), resistor 6 (112), resistor 7 (113), resistor 8 (114), capacitor 3 (115), and APD 116. The numbers after the resistor / capacitor ratings indicate the category of the resistor / capacitor, and the numbers in parentheses are the reference numbers within the entire circuit.

[0038] like Figure 1As shown, voltage source 101 is connected to one end of resistor 2 (106), and the other end of resistor 2 (106) is connected in series with resistor 3 (107) and then connected to the collector of switch transistor 110 and one end of capacitor 2 (115) respectively; the emitter of switch transistor 110 is grounded through resistor 4 (108); the base of switch transistor 110 is connected to one end of capacitor 1 (104) and the output terminal of error amplifier 105 through resistor 5 (109); the other end of capacitor 2 (111) is connected to one end of resistor 6 (112) and one end of capacitor 3 (115) respectively. The resistors 6 (112) and 7 (113) are connected in series and then connected in parallel with the capacitor 3 (115). They are then connected to one end of the resistor 8 (114) and the non-inverting input of the error amplifier 105, and the other end of the resistor 8 (114) is grounded. The other end of the capacitor 1 (104) is connected to one end of the resistor 1 (103) and the inverting input of the error amplifier 105, respectively. The other end of the resistor 1 (103) is connected to one end of the voltage setter 102, and the other end of the voltage setter 102 is grounded.

[0039] like Figure 1 As shown, the voltage input to voltage source 101 is grounded through resistors 2 (106), 3 (107), 6 (112), 7 (113), and 8 (114). The output terminal is connected between resistors 2 (106) and 3 (107) and resistors 6 (112), 7 (113), and 8 (114). This indicates that the output voltage is actually the voltage after the input voltage of voltage source 101 is divided by resistors 2 (106) and 3 (107). Therefore, the values ​​of resistors 2 (106) and 3 (107) will be subject to trade-offs: when the resistance value is too large, the minimum... While lower power consumption at high output voltage results in lower maximum output voltage, it also leads to lower maximum output voltage. Conversely, lower resistance increases maximum output voltage but increases power consumption at minimum output voltage, making it impossible to achieve full-range voltage adjustment. Furthermore, the adjustment circuit itself generates heat. Consequently, the number of APD channels that a DC / DC converter circuit (high voltage module) can support decreases (when the minimum output voltage is 16V, a 200V / 5mA high voltage module with R2=R3=300K can only support a maximum of 16 APD channels), resulting in higher power consumption and poorer filtering performance.

[0040] To address the problem of insufficient voltage regulation and power consumption balance in related technologies, this application provides a voltage regulation circuit for a cell analyzer, comprising: a first switching transistor connected to a voltage source via its emitter and connected to a voltage regulation circuit via its base and collector; and a voltage regulation circuit for regulating the base current of the first switching transistor, converting a first voltage provided by the voltage source into a second voltage, which is then output through the collector of the first switching transistor.

[0041] First, the embodiments of this application can adjust the input first voltage by setting a first switching transistor in the voltage regulation circuit, without the need to use resistors for voltage division, thus achieving full-range voltage regulation and low power consumption.

[0042] Figure 2 This is a schematic diagram of the voltage regulation circuit for a cell analyzer provided in an embodiment of this application, as shown below. Figure 2 As shown, the voltage regulating circuit 20 includes a first switching transistor 201, which is connected to the voltage source 202 through its emitter and to the voltage regulating circuit 203 through its base and collector. The voltage regulating circuit 203 is used to regulate the base current of the first switching transistor 201, convert the first voltage provided by the voltage source 202 into a second voltage, and output it through the collector of the first switching transistor 201.

[0043] Here, voltage source 202 can be a DC-DC converter. For example, the output voltage of current source 202 can be 200V, or other values, which can be set based on actual needs and application scenarios. This application does not limit this.

[0044] Here, the voltage regulation circuit 203 adjusts the base current of the first switching transistor 201 so that the first switching transistor 201 operates in the linear amplification region. In this way, as the base current of the first switching transistor 201 changes, the voltage at the collector of the first switching transistor 201 also changes. Thus, the voltage regulation function can be realized, converting the first voltage into a second voltage, which is then output through the collector of the first switching transistor 201.

[0045] In the embodiments of this application, such as Figure 2 As shown, the second voltage is output from the collector of the first switching transistor 201 and then connected to the APD200 to apply a controllable DC bias high voltage to the two ends of the APD200 to control the gain of the APD200, which is generally between tens of volts and hundreds of volts.

[0046] In some embodiments, the voltage regulation circuit further includes a first filter circuit; the first filter circuit is connected to the collector of the first switching transistor.

[0047] like Figure 3 As shown, the voltage regulating circuit 20 also includes a first filter circuit 204. The first filter circuit 204 can be an RC filter circuit. One end of the resistor 2041 in the first filter circuit 204 is connected to the collector of the first switching transistor 201, and the other end is connected to one end of the capacitor 2042 in the first filter circuit 204. The other end of the capacitor 2042 is grounded.

[0048] Here, the output terminal of the voltage regulating circuit 20 is equipped with a first filter circuit, which makes the DC voltage output by the voltage regulating circuit more stable.

[0049] In some embodiments, the voltage regulating circuit further includes a first resistor; the first resistor is disposed at the base of the first switching transistor; the first resistor is a high-resistance resistor.

[0050] In embodiments of this application, a first resistor may also be provided in the voltage regulation circuit, which is placed at the base of the first switching transistor.

[0051] For example, such as Figure 4 As shown, in the voltage regulation circuit 20, the base of the first switching transistor 201 is provided with a first resistor 205. The first resistor can be a high-value resistor, for example, the first resistor is 5MΩ, 6MΩ or other values. It can be set according to actual needs and application scenarios, and this application does not limit it.

[0052] In the embodiments of this application, since the resistance value of the first resistor can change the base current of the first switching transistor, but will not affect the output of the entire voltage regulation circuit, that is, the collector output voltage of the first switching transistor will not be affected by the resistance value of the first resistor. Even if the resistance value of the first resistor is high, the output second voltage will not be divided by the first resistor. Therefore, the highest output voltage and the lowest output voltage are decoupled here, and the two are no longer related. In addition, the first resistor is set to a high resistance value resistor, so when the output second voltage is low, the power consumption of the voltage regulation circuit will not be very large, and there will be no heat generation.

[0053] For example, at the lowest output voltage, i.e., when the second voltage is 0V, the worst-case power consumption at the lowest output voltage is only 40uA. Therefore, a 200V / 5mA high-voltage module (voltage source) can simultaneously power up to 125 APD channels. The highest output voltage can reach approximately 195V. When the load current is 10uA, if the load current is higher, the resistance in the first filter circuit can be reduced accordingly to further increase the highest output high voltage.

[0054] For example, with a first resistor value of 5MΩ, the voltage regulation circuit is more efficient, and even under the worst power consumption conditions, the voltage regulation circuit will not generate any heat. Furthermore, actual tests show that it can simultaneously support voltage regulation of 48 APD channels.

[0055] In some embodiments, the voltage regulation circuit includes: a voltage setter, an error amplifier, a second switch, a second resistor, a first loop compensation capacitor, and a negative feedback circuit; the voltage setter is connected to the non-inverting input of the error amplifier; the second switch is connected to the output of the error amplifier through its base, grounded through its emitter via the second resistor, and connected to the first switch through its collector; the negative feedback circuit is connected to the collector of the first switch and the inverting input of the error amplifier, respectively; the first loop compensation capacitor is connected in parallel to the non-inverting input and output of the error amplifier.

[0056] like Figure 5 As shown, the voltage regulation circuit 203 includes: a voltage setter 2031, an error amplifier 2032, a second switch 2033, a second resistor 2034, a negative feedback circuit 2035, and a first loop compensation capacitor 2036; the voltage setter 2031 is connected to the non-inverting input terminal of the error amplifier 2032; the second switch 2033 is connected to the output terminal of the error amplifier 2032 through its base, grounded through its emitter via the second resistor 2034, and connected to the first switch 201 through its collector; the negative feedback circuit 2035 is connected to the collector of the first switch 201 and the inverting input terminal of the error amplifier 2032 respectively; the first loop compensation capacitor 2036 is connected in parallel to the non-inverting input terminal and the output terminal of the error amplifier 2032.

[0057] In the embodiments of this application, such as Figure 5 As shown, the second switch 2033 is connected to the first switch 201 through its collector and the first resistor 205.

[0058] In embodiments of this application, a voltage setter can be used to set the output voltage (second voltage) of a voltage regulation circuit. For example, the voltage setter can be a reference source (HVSET).

[0059] In some embodiments, the first switching transistor is a positive-negative-positive bipolar junction transistor.

[0060] In the embodiments of this application, such as Figure 5 As shown, the first switching transistor 201 is configured as a positive-negative-positive bipolar junction transistor (PNP). In this way, the feedback voltage can be fed back to the inverting input terminal of the error amplifier 2032, and the voltage setter 2031 is connected to the non-inverting input terminal of the error amplifier 2032. Otherwise, if the first switching transistor is a negative-positive-negative bipolar junction transistor (NPN), connecting the voltage setter 2031 to the inverting input terminal of the error amplifier 2032 would raise concerns about loop stability.

[0061] In some embodiments, the voltage regulation circuit further includes: a second filter circuit; the second filter circuit is disposed between the voltage setter and the non-inverting input of the error amplifier.

[0062] like Figure 6 As shown, the voltage regulation circuit 203 may also include a second filter circuit 2037, which is located between the voltage setter 2031 and the non-inverting input of the error amplifier 2032.

[0063] For example, such as Figure 6As shown, the second filter circuit can be an RC filter circuit, including resistor 20371 and capacitor 20372. The voltage setter 2031 is connected to the non-inverting input of the error amplifier 2032 via resistor 20371. One end of capacitor 20372 is grounded, and the other end is connected to the non-inverting input of the error amplifier 2032, forming a filter circuit with resistor 20371.

[0064] In the embodiments of this application, a filter circuit is added after the voltage setting terminal. This filter circuit has relatively few limitations, effectively reducing noise without raising concerns about loop stability. Thus, noise is removed before the input error amplifier, and the noise after amplification remains very low.

[0065] like Figure 7 The diagram shown illustrates a performance test of the Power Supply Rejection Ratio (PSRR). It can be seen that 71 represents high-voltage input noise and 72 represents circuit output noise, indicating that the noise has been significantly reduced.

[0066] like Figure 8 As shown, a schematic diagram of a loop stability test is provided. It can be seen that a 100mV rise occurs at the input of the voltage source (DAC) (see...). Figure 8 During the step test of (81) in the middle, the output of the error amplifier (see 81) Figure 8 (82) and the output of the voltage regulation circuit used for the cell analyzer (see 82) Figure 8 The absence of overshoot and oscillation in 83 indicates high loop stability. The bandwidth is limited to 250MHz.

[0067] In some embodiments, there is a linear relationship between the voltage set by the voltage setter and the second voltage.

[0068] In the embodiments of this application, there is a linear relationship between the voltage set by the voltage setter and the second voltage. For example, if the voltage setter is set to 0-5V, then the second voltage is 0-200V. When the voltage setter is set to 0V, the second voltage is 0V, and when the voltage setter is set to 5V, the second voltage is 200V.

[0069] In some embodiments, the negative feedback circuit includes: a third resistor, a fourth resistor, a fifth resistor, and a second loop compensation capacitor; one end of the third resistor is connected to the first filter circuit and the second loop compensation capacitor respectively, and the other end is connected to one end of the fourth resistor; the other end of the fourth resistor is connected to the second loop compensation capacitor; one end of the fifth resistor is grounded, and the other end is connected to the inverting input terminal of the error amplifier, the first loop compensation capacitor, the fourth resistor, and the second loop compensation capacitor.

[0070] like Figure 9 As shown, the negative feedback circuit 2035 includes: a third resistor 20351, a fourth resistor 20352, a fifth resistor 20353, and a second loop compensation capacitor 20354; one end of the third resistor 20351 is connected to the first filter circuit 204 and the second loop compensation capacitor 20354 respectively, and the other end is connected to one end of the fourth resistor 20351; the other end of the fourth resistor 20352 is connected to the second loop compensation capacitor 20354; one end of the fifth resistor 20353 is grounded, and the other end is connected to the inverting input terminal of the error amplifier 2032, the first loop compensation capacitor 2036, the fourth resistor 20352, and the second loop compensation capacitor 20354.

[0071] In the embodiments of this application, when the error amplifier is working normally, the input and output voltage range is within the linear operating region of the error amplifier, so that the linearity and repeatability of the entire circuit can be higher.

[0072] For example, such as Figure 9 As shown, the voltage setter is 0-5V, corresponding to an output second voltage of 0-200V. If the voltage setter is set to 0V, both the non-inverting and inverting inputs of the error amplifier 2032 are 0V. Therefore, the voltage across the fifth resistor 20353 is 0V, and the current is 0. Consequently, the current through the third resistor 20351 and the fourth resistor 20352 is 0, resulting in an output voltage (second voltage) of 0V connected to the APD200. In this case, the second switch 2033 is off, and the first switch 201 is also off. If the voltage setter is 5V... The non-inverting and inverting inputs of the error amplifier 2032 are approximately 5V, but there will be a slight error. At this time, the output of the error amplifier 2032 is positive, the second switch 2033 is turned on, and the first switch 201 is also turned on. The voltage provided by the voltage source is output through the emitter and collector of the first switch 201, which is 200V. When the voltage setter is set to a value between 0 and 5, the second switch 2033 controls the amplification of the first switch 201, which can adjust the current of the collector of the first switch 201, thereby adjusting the output voltage (second voltage).

[0073] like Figure 10 As shown, an exemplary method based on Figure 9 The test simulation diagram of the voltage regulation circuit used in the cell analyzer shows that there is a linear relationship between the voltage set by the voltage setter and the second voltage.

[0074] In some embodiments, a sixth resistor is provided at the base of the second switching transistor.

[0075] like Figure 11 As shown, a sixth resistor 206 is provided at the base of the second switching transistor 203. This improves the stability of the second switching transistor.

[0076] In the embodiments of this application, Figures 2 to 11 In one exemplary implementation: the resistance of resistor 2041 in the first filter circuit 204 can be 200KΩ; the second loop compensation capacitor 2036 and the capacitor 20372 in the second filter circuit 2037 are 0.1uF; the third resistor 20351 and the fourth resistor 20352 are 15MΩ; the first resistor 205 is 5MΩ; the sixth resistor 206 is 15KΩ; the second resistor 2034 and the resistor 20371 in the second filter circuit 3037 can be 1KΩ; the first loop compensation capacitor 2036 can be 10nF; and the fifth resistor 20353 can be 787KΩ. The first switching transistor 201 can be a 2SAR340P; the error amplifier 2032 can be an AD8034; and the second switching transistor 2033 can be a 2SC4061K.

[0077] In some embodiments, the error amplifier is of the zero-drift type.

[0078] In the embodiments of this application, in order to increase the stability of the circuit and ensure that the output high voltage does not change with time and temperature, the error amplifier can be replaced with a zero-drift type.

[0079] In the embodiments of the application, the feedback resistor in the voltage regulation circuit for the cell analyzer can be optionally of a low-temperature drift, high-precision type, wherein, such as Figure 9 and Figure 11 As shown, the feedback resistors include a third resistor 20351, a fourth resistor 20352, and a fifth resistor 20353.

[0080] In the embodiments of this application, a 200V / 5mA high-voltage module (voltage source) can simultaneously provide gain adjustment to at least 48 APDs through the voltage regulation circuit for the cell analyzer of this application, without generating heat and working normally.

[0081] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this application, the sequence numbers of the above steps / processes do not imply a sequential order of execution; the execution order of each step / process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application. The sequence numbers of the above embodiments of this application are merely descriptive and do not represent the superiority or inferiority of the embodiments.

[0082] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0083] The above description is merely an embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A voltage regulating circuit for a cytometer, characterized by, The voltage regulation circuit includes: The first switching transistor is connected to the voltage source through its emitter and to the voltage regulation circuit through its base and collector. The voltage regulation circuit is used to regulate the base current of the first switching transistor, convert the first voltage provided by the voltage source into a second voltage, and output it through the collector of the first switching transistor.

2. The voltage regulating circuit for a cytometer of claim 1, wherein, The voltage regulation circuit also includes a first filter circuit; The first filter circuit is connected to the collector of the first switching transistor.

3. The voltage regulating circuit for a cell analyzer according to claim 1 or 2, characterized in that, The voltage regulating circuit also includes a first resistor; The first resistor is located at the base of the first switching transistor; the first resistor is a high-resistance resistor.

4. The voltage regulating circuit for a cytometer of claim 3, wherein, The voltage regulation circuit includes: a voltage setter, an error amplifier, a second switching transistor, a second resistor, a first loop compensation capacitor, and a negative feedback circuit; The voltage setter is connected to the non-inverting input of the error amplifier; The second switching transistor is connected to the output terminal of the error amplifier through its base, grounded through its emitter via the second resistor, and connected to the first switching transistor through its collector. The negative feedback circuit is connected to the collector of the first switching transistor and the inverting input terminal of the error amplifier, respectively. The first loop compensation capacitor is connected in parallel to the non-inverting input and output of the error amplifier.

5. The voltage regulating circuit for a cytometer of claim 4, wherein, The first switching transistor is a positive-negative-positive bipolar junction transistor.

6. The voltage regulating circuit for a cytometer of claim 4, wherein, The voltage regulation circuit further includes: a second filter circuit; The second filter circuit is located between the voltage setter and the non-inverting input of the error amplifier.

7. The voltage regulating circuit for a cytometer of claim 3, wherein, There is a linear relationship between the voltage set by the voltage setter and the second voltage.

8. The voltage regulating circuit for a cytometer of claim 4, wherein, The negative feedback circuit includes: a third resistor, a fourth resistor, a fifth resistor, and a second loop compensation capacitor; The third resistor has one end connected to the first filter circuit and the second loop compensation capacitor respectively, and the other end connected to one end of the fourth resistor. The other end of the fourth resistor is connected to the second loop compensation capacitor; The fifth resistor has one end grounded and the other end connected to the inverting input of the error amplifier, the first loop compensation capacitor, the fourth resistor, and the second loop compensation capacitor.

9. The voltage regulating circuit for a cytometer of claim 4, wherein, The base of the second switching transistor is provided with a sixth resistor.

10. The voltage regulating circuit for a cell analyzer according to claim 4, characterized in that, The error amplifier is of the zero-drift type.

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