Low-cost MOS tube high-side switch circuit structure

Abstract

The utility model relates to the technical field of circuits, in particular to a low-cost MOS (Metal Oxide Semiconductor) tube high-side switch circuit structure, which is characterized by comprising a PWM (Pulse-Width Modulation) voltage signal amplification system, a PWM signal power amplification system and a boost charge pump system which are connected in sequence, the boost charge pump system comprises a charge and discharge capacitor, a first diode, a second diode, a first filter capacitor, a bleeder resistor, a driving resistor, a second filter capacitor, a voltage stabilizing diode and an MOS tube. The first filter capacitor, the bleeder resistor, the second filter capacitor and the voltage stabilizing diode which are sequentially connected in parallel on the connection path of the first diode and the MOS tube as well as the connection path of the second diode and the MOS tube form a booster circuit and form a voltage conversion circuit structure, so that the cost is effectively reduced, and the reliability of the circuit structure is improved. The application range of the MOS tube high-side switching circuit is expanded, so that the MOS tube high-side switching circuit can be used in more scenes with strict requirements on cost control, and meanwhile, the technology in the circuit field is promoted.

Description

Technical Field

[0001] This utility model relates to the field of circuit technology, and in particular to a low-cost MOS transistor high-side switching circuit structure. Background Technology

[0002] In the current field of electronic circuits, MOSFET high-side switching circuits are widely used in various power electronic devices to achieve efficient power control and distribution. Mainstream MOSFET high-side switching circuits include traditional solutions based on complex driver chips. Their advantages lie in high precision and stability, enabling accurate control of the MOSFET's on / off state, making them suitable for high-end applications with stringent voltage and current control requirements, such as controllers and switching power supplies. However, this approach also has significant disadvantages: high cost. Not only are the driver chips expensive, but the circuit design is also complex, requiring numerous external components. This undoubtedly increases the overall system cost and design difficulty, limiting its widespread adoption in cost-sensitive large-scale production applications.

[0003] In addition, while PMOS transistors can be considered as high-side switches, this choice also faces several challenges. Currently, there are relatively few PMOS models available on the market, limiting designers' options. Furthermore, the manufacturing process for PMOS transistors is more complex than that for NMOS transistors, directly resulting in higher costs.

[0004] Therefore, the applicant found that while MOSFET high-side switching circuits are widely used in today's electronic circuit field, they also have many shortcomings. Solutions based on complex driver chips are often costly and have complex design processes, making them unsuitable for large-scale production scenarios with high cost control requirements. On the other hand, the control circuits for PMOS chips often have limited selection options, are typically expensive, and have poor reliability, failing to meet the needs of cost reduction and quality improvement. Utility Model Content

[0005] To address the above problems, the development of a low-cost MOSFET high-side switching circuit is of paramount practical significance. In the current industrial environment, this novel circuit can effectively reduce costs while ensuring certain performance characteristics. By overcoming the cost challenges in existing technologies, it is expected to significantly expand the application range of MOSFET high-side switching circuits, enabling their use in more production scenarios with stringent cost control requirements. This will further promote the development of power control and distribution technologies in the field of electronic circuits, bringing greater economic benefits and technological innovation to related industries.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A low-cost MOSFET high-side switching circuit structure includes a PWM voltage signal amplification system, a PWM signal power amplification system, and a boost charge pump system connected in sequence.

[0008] The PWM voltage signal amplification system is used to amplify the voltage setting;

[0009] The PWM signal power amplification system is used to amplify the voltage signal power setting;

[0010] The boost charge pump system includes a charging / discharging capacitor, a first diode, a second diode, a first filter capacitor, a bleed resistor, a driving resistor, a second filter capacitor, a Zener diode, and a MOSFET.

[0011] One end of the charging and discharging capacitor is connected to one end of the PWM signal power amplification system, and the other end of the charging and discharging capacitor is connected to one end of the first diode and the second diode respectively. The other end of the first diode and the driving resistor are connected in series in series on the source of the MOS transistor, and the other end of the second diode is connected to the gate of the MOS transistor.

[0012] The first diode, the second diode, and the MOSFET are connected in parallel with the first filter capacitor, the bleeder resistor, the second filter capacitor, and the Zener diode to form a boost circuit and a voltage conversion circuit structure.

[0013] As an improvement, the PWM voltage signal amplification system includes a PWM signal, a first voltage divider resistor, and a comparator. The output terminal of the PWM signal is connected to the positive terminal of the comparator, one end of the first voltage divider resistor is connected to the negative terminal of the comparator, and the other end of the first voltage divider resistor is connected to a pull-up voltage source. The comparator is used for signal comparison and conversion settings.

[0014] As an improvement, a second voltage divider resistor is also connected to the connection point of the first voltage divider resistor and the comparator. The other end of the second voltage divider resistor is grounded. The first voltage divider resistor and the second voltage divider resistor are used in conjunction with other components to control the voltage regulation and stabilization and protection circuit settings.

[0015] As an improvement, the PWM signal power amplification system includes an NPN transistor and a PNP transistor connected in series. One end of each NPN transistor and PNP transistor is connected to the other end of the comparator. The other end of the NPN transistor is connected to the power supply voltage, and the other end of the PNP transistor is grounded. The connection point between the NPN transistor and the PNP transistor is connected to the other end of the charging and discharging capacitor. The NPN transistor and the PNP transistor are used to amplify the current and set the switching modulation.

[0016] As an improvement, a pull-up resistor is also connected to the connection point of the NPN transistor and the PNP transistor with the comparator. The other end of the pull-up resistor is connected to the power supply voltage, and the signal setting is stabilized through the pull-up resistor.

[0017] As an improvement, the connection point between the MOSFET and the Zener diode is connected to the output voltage, and the source of the MOSFET is connected to the input voltage.

[0018] The beneficial effects of this utility model are as follows:

[0019] (1) The present invention provides a low-cost MOS high-side switching circuit structure, which uses a very small number of discrete components to build a high-side MOS driving circuit. Traditional high-side MOS driving circuits often require a relatively complex combination of components, which not only increases the complexity of the circuit, but also has certain disadvantages in terms of cost control and space occupation. The solution proposed in this invention carefully selects a small number of key discrete components. These components are precisely selected and reasonably arranged, which can greatly simplify the circuit structure while ensuring circuit performance.

[0020] (2) The present invention also adopts a charge pump to form a boost circuit to meet the voltage required to drive the MOS transistor. As a circuit structure that can realize voltage conversion, the charge pump plays a crucial role in the present invention. By cleverly designing the parameters and working mode of the charge pump, it can effectively boost the input voltage to the voltage level required to drive the MOS transistor.

[0021] In conclusion, the development of this utility model of a low-cost MOSFET high-side switching circuit has extremely important practical significance. In the current industrial environment, this novel circuit can effectively reduce costs while ensuring certain performance. By overcoming the cost challenges in existing technologies, it is expected to greatly expand the application range of MOSFET high-side switching circuits, enabling their use in more production scenarios with strict cost control requirements. This will further promote the development of power control and distribution technology in the field of electronic circuits, bringing greater economic benefits and technological innovation to related industries. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the circuit structure of this utility model;

[0023] Figure 2 This is a schematic diagram of the NPN transistor conduction structure of this utility model;

[0024] Figure 3 This is a schematic diagram of the conduction structure of the PNP transistor of this utility model.

[0025] In the diagram: I. PWM voltage signal amplification system, II. PWM signal power amplification system, III. Boost charge pump system, 1. PWM signal, 2. First voltage divider resistor, 3. Second voltage divider resistor, 4. Comparator, 40. MOSFET, 5. Pull-up resistor, 6. NPN transistor, 7. PNP transistor, 8. Discharge capacitor, 9. Second diode, 10. First diode, 11. First filter capacitor, 12. Bleeding resistor, 13. Drive resistor, 14. Second filter capacitor, 15. Zener diode, 16. MOSFET, 17. Pull-up voltage source. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0028] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0029] Example 1:

[0030] like Figures 1-3 As shown, a low-cost MOSFET high-side switching circuit structure includes a PWM voltage signal amplification system I, a PWM signal power amplification system II, and a boost charge pump system III connected in sequence.

[0031] The PWM voltage signal amplification system I is used to amplify the voltage setting;

[0032] The PWM signal power amplification system II is used to amplify the voltage signal power setting;

[0033] The boost charge pump system III includes a charging / discharging capacitor 8, a first diode 10, a second diode 9, a first filter capacitor 11, a bleed resistor 12, a driving resistor 13, a second filter capacitor 14, a Zener diode 15, and a MOSFET 16.

[0034] One end of the charging and discharging capacitor 8 is connected to one end of the PWM signal power amplification system II, and the other end of the charging and discharging capacitor 8 is connected to one end of the first diode 10 and the second diode 9 respectively. The other end of the first diode 10 and the driving resistor 13 are connected in series in series on the source of the MOS transistor 16, and the other end of the second diode 9 is connected to the gate of the MOS transistor 16.

[0035] The first diode 10, the second diode 9, and the MOS transistor 16 are connected in parallel with the first filter capacitor 11, the bleeder resistor 12, the second filter capacitor 14, and the Zener diode 15, forming a boost circuit and a voltage conversion circuit structure.

[0036] The PWM voltage signal amplification system I includes a PWM signal 1, a first voltage divider resistor 2, and a comparator 4. The output terminal of the PWM signal 1 is connected to the positive terminal of the comparator 4. One end of the first voltage divider resistor 2 is connected to the negative terminal of the comparator 4, and the other end of the first voltage divider resistor 2 is connected to a pull-up voltage source 17. The comparator 4 is used for signal comparison and conversion settings.

[0037] The connection point between the first voltage divider resistor 2 and the comparator 4 is also connected to a second voltage divider resistor 3. The other end of the second voltage divider resistor 3 is grounded. The first voltage divider resistor 2 and the second voltage divider resistor 3, together with other components, control the voltage regulation and stabilization and protection circuit settings.

[0038] The PWM signal power amplification system II includes an NPN transistor 6 and a PNP transistor 7 connected in series. One end of each of the NPN transistor 6 and the PNP transistor 7 is connected to the other end of the comparator 4. The other end of the NPN transistor 6 is connected to the power supply voltage, and the other end of the PNP transistor 7 is grounded. The connection point of the NPN transistor 6 and the PNP transistor 7 is connected to the other end of the charging and discharging capacitor 8. The NPN transistor 6 and the PNP transistor 7 are used for current amplification and switching modulation settings.

[0039] A pull-up resistor 5 is also connected to the connection point of the NPN transistor 6, the PNP transistor 7, and the comparator 4. The other end of the pull-up resistor 5 is connected to the power supply voltage, and the signal is stabilized by the pull-up resistor 5.

[0040] The connection point between the MOSFET 16 and the Zener diode 15 is connected to the output voltage, and the source of the MOSFET 16 is connected to the input voltage.

[0041] It should be added that the functions of each circuit are as follows: The charging and discharging capacitor 8 is used to store and release charge, and is a key component for voltage conversion. It increases the voltage by transferring charge through charging and discharging; The first diode 10 and the second diode 9 mainly function as unidirectional conductors, guiding the current to flow in a specific direction to ensure the correct charging and discharging of the capacitor and prevent current backflow; The first filter capacitor 11 and the second filter capacitor 14 mainly filter out the ripple in the output voltage, making the output voltage more stable and providing a stable DC voltage for the load; The bleeder resistor 12 is used to release the charge stored in the capacitor when the system stops working or malfunctions, ensuring safety and preventing residual charge from damaging the equipment; The drive resistor 13 is used to limit the drive signal current, protecting the drive circuit and related components, and ensuring the stable and reliable operation of the system; The Zener diode 15 is used to stabilize the output voltage. When the output voltage exceeds its Zener value, it conducts to clamp the voltage at a stable value and prevent the overvoltage from damaging the load.

[0042] To further explain, the function of the PWM signal amplification system I is to boost the voltage system from 3.3V or 5V to 12V by the MCU or other system that can generate PWM control signals through the conversion of comparator 4. The function of the signal power amplification system II is to amplify the driving capability of the PWM voltage signal from comparator 4, since the driving capability of the PWM voltage signal is very low. This is achieved by using an amplification circuit to amplify the driving capability of the first diode 10 and the second diode 9, and then using appropriate biasing and connection.

[0043] The working principle of its boost charge pump III is that NPN transistor 6 and PNP transistor 7 are alternately turned on. When PNP transistor 7 is turned on, the charging stage begins. The current starts from the input voltage and flows sequentially through Zener diode 15, second filter capacitor 14, drive resistor 13, bleed resistor 12, and first filter capacitor 11 to first diode 10 and second diode 9. This current is finally delivered to charge / discharge capacitor 8 through first diode 10, causing the voltage across charge / discharge capacitor 8 to rise to the input voltage value. Then, the first filter capacitor 11 and second filter capacitor 14 absorb voltage fluctuation energy, smoothing the output voltage and reducing ripple. Zener diode 15 directs excess voltage through other circuits, stabilizing the output voltage at the set value. Finally, the current flows through the bleed resistor... 12 provides a discharge path for the capacitor, slowly releasing the stored charge. Finally, the current of the drive signal is adjusted by the drive resistor 13 to ensure the stable operation of the charge pump system. The current flowing through it is finally connected to ground. When the NPN transistor 6 is turned on, the voltage of the charging and discharging capacitor 8 is raised to the output voltage value plus the supply voltage value. At this time, the voltage difference between the gate and source of the MOSFET 16, without considering the voltage drop of the diode, will be equal to the supply voltage. This voltage will meet the turn-on voltage of the MOSFET. During its discharge phase, the circuit is switched. The charging and discharging capacitor 8 discharges through the second diode 9, and the charge is transferred to the output voltage, causing the output voltage to rise. At the same time, the voltage control signal is amplified by the PWM voltage signal amplification system I and the PWM signal power amplification system II.

[0044] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A low-cost MOSFET high-side switching circuit structure, characterized in that: It includes a PWM voltage signal amplification system (I), a PWM signal power amplification system (II), and a boost charge pump system (III) connected in sequence. The PWM voltage signal amplification system (I) is used to amplify the voltage setting; The PWM signal power amplification system (II) is used to amplify the voltage signal power setting; The boost charge pump system (III) includes a charge / discharge capacitor (8), a first diode (10), a second diode (9), a first filter capacitor (11), a discharge resistor (12), a drive resistor (13), a second filter capacitor (14), a Zener diode (15), and a MOSFET (16). One end of the charging and discharging capacitor (8) is connected to one end of the PWM signal power amplification system (II), and the other end of the charging and discharging capacitor (8) is connected to one end of the first diode (10) and the second diode (9) respectively. The other end of the first diode (10) and the driving resistor (13) are connected in series on the source of the MOS transistor (16), and the other end of the second diode (9) is connected to the gate of the MOS transistor (16). The first diode (10), the second diode (9), and the MOS transistor (16) are connected in parallel with the first filter capacitor (11), the bleeder resistor (12), the second filter capacitor (14), and the Zener diode (15) to form a boost circuit and a voltage conversion circuit structure.

2. The low-cost MOS transistor high-side switching circuit structure according to claim 1, characterized in that: The PWM voltage signal amplification system (I) includes a PWM signal (1), a first voltage divider resistor (2) and a comparator (4). The output terminal of the PWM signal (1) is connected to the positive terminal of the comparator (4). One end of the first voltage divider resistor (2) is connected to the negative terminal of the comparator (4), and the other end of the first voltage divider resistor (2) is connected to the pull-up voltage source (17). The comparator (4) is used to compare and convert the signal.

3. The low-cost MOS transistor high-side switching circuit structure according to claim 2, characterized in that: The connection point between the first voltage divider resistor (2) and the comparator (4) is also connected to a second voltage divider resistor (3). The other end of the second voltage divider resistor (3) is grounded. The first voltage divider resistor (2) and the second voltage divider resistor (3) work together with other components to control the voltage regulation and stabilization and the protection circuit settings.

4. The low-cost MOS transistor high-side switching circuit structure according to claim 2, characterized in that: The PWM signal power amplification system (II) includes an NPN transistor (6) and a PNP transistor (7) connected in series. One end of the NPN transistor (6) and the PNP transistor (7) are connected to the other end of the comparator (4). The other end of the NPN transistor (6) is connected to the power supply voltage, and the other end of the PNP transistor (7) is grounded. The connection point of the NPN transistor (6) and the PNP transistor (7) is connected to the other end of the charging and discharging capacitor (8). The NPN transistor (6) and the PNP transistor (7) are used to amplify the current and set the switching modulation.

5. The low-cost MOS transistor high-side switching circuit structure according to claim 4, characterized in that: A pull-up resistor (5) is also connected to the connection point of the NPN transistor (6), the PNP transistor (7), and the comparator (4). The other end of the pull-up resistor (5) is connected to the power supply voltage, and the signal setting is stabilized through the pull-up resistor (5).

6. The low-cost MOS transistor high-side switching circuit structure according to claim 1, characterized in that: The connection point between the MOS transistor (16) and the Zener diode (15) is connected to the output voltage, and the source of the MOS transistor (16) is connected to the input voltage.

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