A circuit structure for driving a MOSFET

Abstract

The application provides a circuit structure for driving MOSFET, which comprises a chip power supply and a chip, wherein the chip is provided with the following structures: a reference voltage module, a current detection, a register, a selection switch, an N-type driving structure and a P-type driving structure; compared with the circuit structure with only one type of driving, the application can directly drive N-type or P-type MOS without converting the level signal by external circuit; compared with the scheme of simultaneously integrating two types of driving circuit structures, the application saves chip pins, and only one driving structure is actually working after judging the type of peripheral MOSFET, thereby saving chip power consumption; under the premise of not increasing the peripheral cost and chip pins of the existing equipment, the internal structure design of the integrated circuit can realize the problem that one chip pin can drive N-type and P-type MOSFET at will.

Description

Technical Field

[0001] This invention mainly relates to the field of MOSFET driving circuits, and specifically to a circuit structure for driving MOSFETs. Background Technology

[0002] Currently, MOSFETs and their driving circuits are used very frequently in circuit design. However, current driving circuits can often only drive one type of MOSFET, such as only N-type or only P-type MOSFETs.

[0003] As attached Figure 1 The diagram shows a common structure for driving N-type MOSFETs. It can only directly drive N-type MOSFETs, and the driving logic is a high level when on and a high impedance state when off. When a practical application requires driving a P-type MOSFET, the conversion must be performed using other circuits in the external circuitry.

[0004] As attached Figure 2 As shown, two additional resistors and an NPN transistor are added to achieve the drive conversion, thus converting the high level during startup to a low level, while maintaining the high impedance state. This approach is rather wasteful of the cost of external components.

[0005] As attached Figure 3 The diagram shows a common structure for driving a P-type MOSFET. It can only directly drive P-type MOSFETs, with the driving logic being low level when on and high impedance when off. When a practical application requires driving an N-type MOSFET, the conversion must be achieved using other circuitry in the external circuitry.

[0006] As attached Figure 4 As shown, two additional resistors and a PNP transistor are added to achieve the drive conversion, thus converting the low level when turned on to a high level, while the high-impedance state remains a high-impedance state. This solution also wastes the cost of external components.

[0007] like Figure 5 As shown, its integrated circuit design has two sets of driving systems that can drive N-type and P-type MOSFETs respectively, and drive external MOSFETs through two chip pins. Depending on the type of MOSFET used, it can be connected to the corresponding pin.

[0008] As attached Figure 6 To drive an N-type MOSFET.

[0009] Appendix Figure 7 This method drives a P-type MOSFET. However, such a solution requires the chip to provide additional pins, which is not conducive to the miniaturization and integration of chip design. Summary of the Invention

[0010] The problem the invention aims to solve

[0011] This invention provides a circuit structure for driving MOSFETs. In order to overcome the situation where driving N-type and P-type MOSFETs may be encountered in actual use, without increasing the cost of external components or adding chip pins, the internal structure design of the integrated circuit can realize the arbitrary driving of N-type and P-type MOSFETs with a single chip pin.

[0012] Technical solution

[0013] To achieve the above objectives, the technical solution provided by the present invention is as follows: a circuit structure for driving MOSFETs, including a chip power supply and a chip, wherein the chip has the following pre-set structure.

[0014] The reference voltage module generates a reference voltage signal after being powered on.

[0015] Current detection is used to detect the direction of the supply current to the reference voltage signal and output the detection result.

[0016] A register works in conjunction with the current sensor and receives the detection result output by the current sensor. The register compares the detection result output by the current sensor with a built-in threshold and outputs a control signal.

[0017] The selector switch is controlled by a register structure and is electrically connected to the reference voltage module.

[0018] The N-type drive structure is a push-pull structure that is electrically connected to the selector switch.

[0019] The P-type drive structure is an open-circuit structure that is electrically connected to the selector switch.

[0020] Furthermore, the chip includes a CO output pin, wherein the CO output pin is electrically connected to an external N-type MOSFET or P-type MOSFET.

[0021] Furthermore, when the chip power supply first powers on the chip, the register defaults to 00.

[0022] Furthermore, the reference voltage module provides an initial reference voltage signal as an intermediate value.

[0023] Furthermore, the current detection outputs the detection result based on the current direction of the reference voltage signal. If the current direction of the reference voltage signal is from the inside of the chip to the outside, the detection result of the current detection is output to the register, and the value of the register is modified to 10. Conversely, if the current direction is from the inside of the chip to the outside, the value of the register is modified to 11.

[0024] Furthermore, if the value of the register is 10, the selection switch is turned on to connect the N-type drive structure, while the reference voltage module and the P-type drive structure are turned off. If the value of the register is 11, the selection switch is turned on to connect the P-type drive structure, while the reference voltage module and the N-type drive structure are turned off.

[0025] Furthermore, when the CO output pin is connected to an N-type MOSFET, the current direction within the chip is from the inside out, and its current loop is as follows:

[0026] 1) Powered by the chip power supply, the current flows from the positive terminal of the chip power supply through the reference voltage module to form an intermediate reference voltage signal. The value of the register is 00, and the selector switch is connected to the reference voltage module.

[0027] 2) The current is output to the external N-type MOSFET after passing through the selector switch and CO output pin.

[0028] 3) The current flows through resistor R1, resistor R2 and the diode of the N-type MOSFET in sequence to reach the negative terminal of the chip power supply, thus completing the current loop.

[0029] Furthermore, when the CO output pin is connected to a P-type MOSFET, the current direction within the chip is from the outside to the inside, and its current loop is as follows:

[0030] 1) Powered by the chip power supply, the current flows from the positive terminal of the chip power supply through the reference voltage module to form an intermediate reference voltage signal. The value of the register is 00, and the selector switch is connected to the reference voltage module.

[0031] 2) The current flows through the diode, resistor R2, and resistor R1 of the P-type MOSFET in sequence.

[0032] 3) Current flows out from the P-type MOSFET and through the CO output pin to the selector switch.

[0033] 4) The current flows to the reference voltage module via the selector switch, completing the current loop construction.

[0034] Furthermore, the CO output pin is selectively connected to either an N-type drive structure or a P-type drive structure via a selection switch.

[0035] Furthermore, the selection switch and the register are reset when the chip power supply is turned on or off.

[0036] Beneficial effects

[0037] Compared with the prior art, the technical solution provided by this invention has the following advantages:

[0038] This invention provides a circuit structure for driving MOSFETs. Compared with circuit structures that only have one driving type, this invention can directly drive N-type or P-type MOSFETs without the need for external circuits to convert the signal level.

[0039] This invention provides a circuit structure for driving MOSFETs. Compared with the solution of integrating two driving circuit structures at the same time, this invention saves chip pins, and after internally determining the type of the external MOSFET, only one driving structure is actually working, thus saving chip power consumption. Attached Figure Description

[0040] Figure 1 : IC driving N-type MOSFET circuit diagram.

[0041] Figure 2 : Circuit diagram of IC driving P-type MOSFET with N-type MOSFET driving structure.

[0042] Figure 3 : IC driving P-type MOSFET circuit diagram.

[0043] Figure 4 : Circuit diagram of IC driving N-type MOSFET with P-type MOSFET drive structure.

[0044] Figure 5 A simplified diagram of an IC that simultaneously possesses two driving structures.

[0045] Figure 6 : Circuit diagram of an IC driving an N-type MOSFET that has two driving structures.

[0046] Figure 7 A circuit diagram of an IC driving a P-type MOSFET that simultaneously possesses two driving structures.

[0047] Figure 8 Internal diagram of the driving circuit structure of the present invention

[0048] Figure 9 The circuit structure for driving the MOSFET of the present invention includes a circuit diagram for driving an N-type MOSFET.

[0049] Figure 10 The circuit structure for driving the MOSFET of the present invention includes a circuit diagram of a P-type MOSFET.

[0050] Figure 11 : A flowchart illustrating the circuit structure of the driving MOSFET of the present invention. Detailed Implementation

[0051] To facilitate understanding of the present invention, a more complete description of the invention will be given below with reference to the accompanying drawings, which illustrate several embodiments of the invention. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the invention will be more thorough and complete.

[0052] 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 invention pertains; the terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to limit the invention; the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Example

[0053] Reference Figure 8-11 A circuit structure for driving MOSFETs includes a chip power supply and a chip, wherein the chip has the following pre-set structure.

[0054] The reference voltage module generates a reference voltage signal after being powered on.

[0055] Current detection is used to detect the direction of the supply current to the reference voltage signal and output the detection result.

[0056] A register works in conjunction with the current sensor and receives the detection result output by the current sensor. The register compares the detection result output by the current sensor with a built-in threshold and outputs a control signal.

[0057] The selector switch is controlled by a register structure and is electrically connected to the reference voltage module.

[0058] The N-type drive structure is a push-pull structure that is electrically connected to the selector switch.

[0059] The P-type drive structure is an open-circuit structure that is electrically connected to the selector switch.

[0060] In this embodiment, as Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown, the chip includes a CO output pin, which is electrically connected to an external N-type MOSFET or P-type MOSFET.

[0061] In this embodiment, as Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown, when the chip power supply first powers on the chip, the register defaults to 00.

[0062] In this embodiment, as Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown, the reference voltage module provides an initial reference voltage signal as an intermediate value.

[0063] In this embodiment, as Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown, the current detection outputs the detection result based on the current direction of the reference voltage signal. If the current direction of the reference voltage signal is from the inside of the chip to the outside, the detection result of the current detection is output to the register, and the value of the register is modified to 10. Otherwise, the value of the register is modified to 11.

[0064] In this embodiment, as Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown, when the value of the register is 10, the selection switch is turned on to connect the N-type drive structure, while the reference voltage module and the P-type drive structure are turned off. When the value of the register is 11, the selection switch is turned on to connect the P-type drive structure, while the reference voltage module and the N-type drive structure are turned off.

[0065] In this embodiment, as Figure 8 , Figure 9 and Figure 11 As shown, when the CO output pin is connected to an N-type MOSFET, the current direction within the chip is from the inside out, and its current loop is as follows:

[0066] 1) Powered by the chip power supply, the current flows from the positive terminal of the chip power supply through the reference voltage module to form an intermediate reference voltage signal. The value of the register is 00, and the selector switch is connected to the reference voltage module.

[0067] 2) The current is output to the external N-type MOSFET after passing through the selector switch and CO output pin.

[0068] 3) The current flows through resistor R1, resistor R2 and the diode of the N-type MOSFET in sequence to reach the negative terminal of the chip power supply, thus completing the current loop.

[0069] In this embodiment, as Figure 8 , Figure 10 and Figure 11 As shown, when the CO output pin is connected to a P-type MOSFET, the current direction within the chip is from the outside to the inside, and its current loop is as follows:

[0070] 1) Powered by the chip power supply, the current flows from the positive terminal of the chip power supply through the reference voltage module to form an intermediate reference voltage signal. The value of the register is 00, and the selector switch is connected to the reference voltage module.

[0071] 2) The current flows through the diode, resistor R2, and resistor R1 of the P-type MOSFET in sequence.

[0072] 3) Current flows out from the P-type MOSFET and through the CO output pin to the selector switch.

[0073] 4) The current flows to the reference voltage module via the selector switch, completing the current loop construction.

[0074] In this embodiment, as Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown, the CO output pin is selectively connected to either an N-type drive structure or a P-type drive structure via a selector switch.

[0075] In this embodiment, as Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown, the selection switch and the register are reset when the chip power supply is turned on or off.

[0076] In this embodiment:

[0077] This structure is generally packaged in a chip. The chip and its peripheral circuits are designed on a PCB board and the chip power is turned on. Once the chip is powered on, a complete power supply circuit can be formed inside the chip to provide power to the other modules of the chip.

[0078] After the internal power supply of the chip is completed, the reference voltage module can generate a medium-sized voltage (5V is commonly used, but it can also be set to other voltages as needed, such as 3.3V, 9V, etc.). At the same time, after the chip is powered on for the first time, the register is in the initial default state, usually 00. When the register is in the initial default state of 00, the connection item of the selection switch is connected to the reference voltage module, forming a connection loop.

[0079] The chip's CO output pin works with a selector switch inside the chip and is connected to a MOSFET externally. At this time, the selector switch inside the chip is connected to the reference voltage. The type of the externally connected MOSFET is currently unconfirmed, but there will only be two types: an N-type MOSFET and a P-type MOSFET.

[0080] When an N-type MOSFET is connected externally, since the N-type MOSFET is generally connected to the negative terminal, the current flows outward from the reference voltage. Similarly, when a P-type MOSFET is connected externally, since the P-type MOSFET is generally connected to the positive terminal, the current flows inward from the outside towards the reference voltage.

[0081] When different types of MOSFETs are connected externally, the current flows in different directions. The current detection module can detect these differences in current direction and determine the type of external MOSFET based on the different current directions, and record the results in the register.

[0082] When the current detection module detects that the current is flowing outward, it confirms that the external MOSFET is an N-type MOSFET and adjusts the value of the register to 10; when the current detection module detects that the current is flowing inward, it confirms that the external MOSFET is a P-type MOSFET and adjusts the value of the register to 11.

[0083] When the current detection module detects the current direction, it records the value in the register. At the same time, this value will also change the connection of the selector switch. When the external MOSFET is an N-type MOSFET and the value of the register is adjusted to 10, the selector switch will connect the selection to the N-type drive structure. When the external MOSFET is a P-type MOSFET and the value of the register is adjusted to 11, the selector switch will connect the selection to the P-type drive structure.

[0084] Once the selection option of the selector switch is adjusted, the value of the register, once determined, will ensure the stability of subsequent selector switches.

[0085] Once the selection option of the selector switch is adjusted and one of the driving structures is determined, the reference voltage module inside the chip and the other driving structure will be disconnected, thus eliminating the current loop and achieving a similar shutdown effect, thereby meeting the requirement of reducing power consumption.

[0086] Once the driving structure is determined, the chip can continue to operate in its normal mode.

[0087] When the chip's power supply is disconnected, the chip's internal state becomes invalid. When the power is restored, the aforementioned selection process will be repeated to select a suitable driving structure again.

[0088] The above-described embodiments are merely illustrative of certain implementations of the present invention, and are described in a relatively specific and detailed manner. However, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A circuit structure for driving a MOSFET, including a chip power supply, characterized in that: It also includes a chip, which has the following pre-set structure: The reference voltage module generates a reference voltage signal after being powered on. Current detection is used to detect the direction of the supply current to the reference voltage signal and output the detection result; A register works in conjunction with the current sensor and receives the detection result output by the current sensor. The register compares the detection result output by the current sensor with a built-in threshold and outputs a control signal. The selector switch is controlled by a register structure and is electrically connected to the reference voltage module. The N-type drive structure is a push-pull structure that is electrically connected to the selector switch. The P-type drive structure is an open-circuit structure that is electrically connected to the selector switch. The current detection outputs the detection result based on the current direction of the reference voltage signal. If the current direction of the reference voltage signal is from the inside of the chip to the outside, the detection result of the current detection is output to the register, and the value of the register is modified to 10. Otherwise, the value of the register is modified to 11. When the value of the register is 10, the selection switch is turned on to connect the N-type drive structure, while the reference voltage module and the P-type drive structure are turned off. When the value of the register is 11, the selection switch is turned on to connect the P-type drive structure, while the reference voltage module and the N-type drive structure are turned off.

2. The circuit structure for driving a MOSFET according to claim 1, characterized in that: The chip includes a CO output pin, which is electrically connected to an external N-type MOSFET or P-type MOSFET.

3. The circuit structure for driving a MOSFET according to claim 1, characterized in that: When the chip power supply first powers on the chip, the register defaults to 00.

4. The circuit structure for driving a MOSFET according to claim 1, characterized in that: The reference voltage module provides an initial reference voltage signal as an intermediate value.

5. The circuit structure for driving a MOSFET according to claim 2, characterized in that: When the CO output pin is connected to an N-type MOSFET, the current direction within the chip is from the inside out, and its current loop is as follows: 1) Powered by the chip power supply, the current flows from the positive terminal of the chip power supply through the reference voltage module to form an intermediate reference voltage signal. The value of the register is 00, and the selector switch is connected to the reference voltage module. 2) The current is output to the external N-type MOSFET after passing through the selector switch and the CO output pin; 3) The current flows through resistor R1, resistor R2 and diode of the N-type MOSFET in sequence to the negative terminal of the chip power supply, thus completing the current loop.

6. The circuit structure for driving a MOSFET according to claim 2, characterized in that: When the CO output pin is connected to a P-type MOSFET, the current direction within the chip is from the outside to the inside, and its current loop is as follows: 1) Powered by the chip power supply, current flows from the positive terminal of the chip power supply, through the reference voltage module, forming an intermediate reference voltage signal. The register value is 00. The selector switch connects to the reference voltage module. 2) The current flows sequentially through the diode, resistor R2, and resistor R1 within the P-type MOSFET; 3) Current flows out from the P-type MOSFET and through the CO output pin to the selector switch; 4) The current flows to the reference voltage module via the selector switch, completing the current loop construction.

7. The circuit structure for driving a MOSFET according to claim 2, characterized in that: The CO output pin is selectively connected to either an N-type drive structure or a P-type drive structure via a selector switch.

8. The circuit structure for driving a MOSFET according to claim 1, characterized in that: The selection switch and the register are reset when the chip power supply is turned on or off.

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