High-performance secondary side synchronous rectification controller with built-in MOS

Abstract

The invention discloses a high-performance secondary side synchronous rectification controller with a built-in MOS (Metal Oxide Semiconductor), which comprises a control chip, and is characterized in that the control chip comprises an input module, a control logic module, an output module, a protection circuit module, a driving circuit module, a communication interface module and a self-powered circuit module; a traditional rectifier diode is replaced by a power MOSFET with extremely low on-resistance, conduction loss in the rectification process is greatly reduced, power supply efficiency can be remarkably improved in high-frequency and large-current power supply conversion application, energy waste can be effectively reduced, and equipment operation cost can be reduced; meanwhile, through an accurate control algorithm, the synchronous rectification controller can effectively reduce ripples of the output voltage, improve the stability and precision of the output voltage, provide a more stable and purer power supply for the load, and facilitate improvement of the performance and the service life of load equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of synchronous rectification, in particular to a high-performance secondary-side synchronous rectification controller with built-in MOS. Background Art

[0002] As we all know, synchronous rectifier controllers are widely used in various fields, including computer power supplies, consumer electronics, and industrial power supplies. Synchronous rectifier controllers achieve synchronous control of the rectification process by controlling the switching action of power MOSFETs. In a switching power supply, when the primary-side switch is turned on, energy is transferred to the secondary side. The controller also turns on the secondary-side synchronous rectifiers, enabling current to flow efficiently from the transformer secondary to the load. When the primary-side switch is turned off, the synchronous rectifiers also turn off quickly to reduce reverse current and losses. With the continuous advancement of power supply technology, synchronous rectifier controllers are moving towards higher integration, higher efficiency, lower power consumption, and greater intelligence. Therefore, we propose a high-performance secondary-side synchronous rectifier controller with built-in MOSFETs. Summary of the Invention

[0003] The object of the present invention is to provide a high-performance secondary-side synchronous rectification controller with built-in MOS to solve the problems raised in the above background technology.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A high-performance secondary-side synchronous rectification controller with built-in MOS, comprising a control chip, the control chip comprising an input module, a control logic module, an output module, a protection circuit module, a drive circuit module, a communication interface module, and a self-powered circuit module, wherein the input module is connected to the control logic module, the control logic module is connected to the output module, the output module is connected to the protection circuit module, the protection circuit module is connected to the drive circuit module, the drive circuit module is connected to the communication interface module, and the communication interface module is connected to the self-powered circuit module; the input module comprises a voltage detection unit and a current detection unit, wherein the voltage detection unit is connected to the current detection unit; the The control logic module includes a logic control unit, a PWM generation unit, and a dead time control unit. The logic control unit is connected to the PWM generation unit, and the PWM generation unit is connected to the dead time control unit. The output module includes a drive circuit and a power MOSFET. The drive circuit is connected to the power MOSFET. The protection circuit module includes an over-temperature protection circuit, an under-voltage protection circuit, and an over-current protection circuit. The over-temperature protection circuit is connected to the under-voltage protection circuit, and the under-voltage protection circuit is connected to the over-current protection circuit. The drive circuit module includes a gate drive circuit. The communication interface module includes a digital communication interface. The self-powered circuit module includes a self-powered unit.

[0006] As a further solution of the present invention: the voltage detection circuit is used to monitor the input voltage and provide voltage information to the control chip, so that it can adjust the control strategy according to the changes in the input voltage, ensure that the chip operates within the appropriate voltage range, and realize overvoltage and undervoltage protection functions at the same time; the current detection circuit detects the input or output current of the power supply through various components such as sampling resistors or current transformers.

[0007] As a further solution of the present invention: the logic control unit generates a control signal to drive the output module based on the voltage and current information provided by the input module, as well as internal preset parameters and algorithms, to achieve precise control of the synchronous rectification process; the PWM generation unit generates a pulse width modulation signal for controlling the on and off time of the power MOSFET; and the dead time control unit is responsible for setting the dead time between the main switch and the synchronous rectification switch drive signal to avoid cross conduction of the MOSFET.

[0008] As a further solution of the present invention: the drive circuit amplifies and shapes the control signal generated by the control module, provides sufficient drive current and voltage for the power MOSFET, and ensures that the power MOSFET can respond to the control signal quickly and accurately; the power MOSFET is the key executive element of the synchronous rectification control chip.

[0009] As a further solution of the present invention: the over-temperature protection circuit monitors the temperature inside or outside the control chip, and triggers the protection mechanism when the temperature exceeds a set threshold.

[0010] As a further solution of the present invention: when the input voltage or the supply voltage of the chip is lower than a certain value, the undervoltage protection circuit starts the undervoltage protection, causing the chip to enter a low power consumption mode or stop working.

[0011] As a further solution of the present invention: when the overcurrent protection circuit detects that the output current exceeds a set maximum value, it quickly takes measures to limit the current.

[0012] As a further solution of the present invention: the gate drive circuit amplifies and shapes the control signal generated by the control logic module, provides drive current and voltage to the gate of the power MOSFET, so that the power MOSFET can respond to the control signal quickly and accurately.

[0013] As a further solution of the present invention: the digital communication interface is used to communicate with other chips or microcontrollers. Through the digital communication interface, the synchronous rectification controller can receive external control instructions and parameter settings, and at the same time feed back its own working status and related information to the external device.

[0014] As a further solution of the present invention: the self-powered unit can obtain energy from the input power supply or the output power supply through the internal circuit to provide power for the operation of the control chip itself.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] This high-performance secondary-side synchronous rectification controller with built-in MOS uses a control chip consisting of an input module, a control logic module, an output module, a protection circuit module, a drive circuit module, a communication interface module, and a self-powered circuit module. It replaces traditional rectifier diodes with power MOSFETs with extremely low on-resistance, greatly reducing conduction losses during the rectification process. In high-frequency, high-current power conversion applications, it can significantly improve power efficiency, effectively reduce energy waste, and lower equipment operating costs. At the same time, through precise control algorithms, the synchronous rectification controller can effectively reduce output voltage ripple, improve output voltage stability and accuracy, provide more stable and pure power to the load, and help improve the performance and life of the load equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The figure is a schematic diagram of the structure of the high-performance secondary-side synchronous rectification controller with built-in MOS of the present invention.

[0018] Figure 2 Schematic diagram of the pin package of the high-performance secondary-side synchronous rectification controller with built-in MOS of the present invention.

[0019] Figure 3 This is a schematic diagram of the internal block diagram of the high-performance secondary-side synchronous rectification controller with built-in MOS of the present invention.

[0020] Figure 4 Schematic diagram of the structure of the high-performance secondary-side synchronous rectification controller in the present invention. DETAILED DESCRIPTION

[0021] In one embodiment, Figures 1-4As shown, a high-performance secondary-side synchronous rectification controller with built-in MOS includes a control chip, which includes an input module, a control logic module, an output module, a protection circuit module, a drive circuit module, a communication interface module, and a self-powered circuit module. The input module is connected to the control logic module, the control logic module is connected to the output module, the output module is connected to the protection circuit module, the protection circuit module is connected to the drive circuit module, the drive circuit module is connected to the communication interface module, and the communication interface module is connected to the self-powered circuit module; the input module includes a voltage detection unit and a current detection unit, and the voltage detection unit is connected to the current detection unit. connection; the control logic module includes a logic control unit, a PWM generation unit, and a dead time control unit, the logic control unit is connected to the PWM generation unit, and the PWM generation unit is connected to the dead time control unit; the output module includes a drive circuit and a power MOSFET, and the drive circuit is connected to the power MOSFET; the protection circuit module includes an over-temperature protection circuit, an under-voltage protection circuit and an over-current protection circuit, the over-temperature protection circuit is connected to the under-voltage protection circuit, and the under-voltage protection circuit is connected to the over-current protection circuit; the drive circuit module includes a gate drive circuit; the communication interface module includes a digital communication interface; the self-powered circuit module includes a self-powered unit;

[0022] The voltage detection circuit monitors the input voltage and provides voltage information to the control chip, enabling it to adjust its control strategy based on changes in the input voltage, ensuring the chip operates within the appropriate voltage range while also implementing overvoltage and undervoltage protection. The current detection circuit detects the input or output current of the power supply through various components, such as sampling resistors or current transformers. This circuit provides current feedback signals to the control chip for overcurrent protection, constant current control, and other functions.

[0023] The logic control unit is the core part of the chip. Based on the voltage and current information provided by the input module, as well as the internal preset parameters and algorithms, it generates control signals to drive the output module to achieve precise control of the synchronous rectification process. For example, it will adjust the switching frequency and duty cycle of the MOSFET based on the feedback of the output voltage to maintain a stable output. The PWM generation unit generates a pulse width modulation (PWM) signal to control the on and off time of the power MOSFET. By changing the duty cycle of the PWM signal, the output voltage can be adjusted. The dead time control unit is responsible for setting the dead time between the main switch and the synchronous rectification switch drive signal to avoid cross conduction of the MOSFET and prevent problems such as short circuits.

[0024] The drive circuit amplifies and shapes the control signal generated by the control module, providing sufficient drive current and voltage for the power MOSFET, ensuring that the power MOSFET can respond to the control signal quickly and accurately to achieve efficient rectification. The power MOSFET is a key executive component of the synchronous rectification control chip. With its extremely low on-resistance, it replaces traditional rectifier diodes, greatly reducing rectification losses and improving power conversion efficiency.

[0025] Overtemperature protection circuit: monitors the temperature inside or outside the control chip. When the temperature exceeds the set threshold, it triggers the protection mechanism, such as reducing the chip's operating frequency, shutting off the power MOSFET, or taking other heat dissipation measures to prevent the chip from being damaged by overheating and extend the chip's service life.

[0026] Undervoltage protection circuit: When the input voltage or the chip's supply voltage is lower than a certain value, the undervoltage protection is activated, causing the chip to enter low-power mode or stop working, to prevent the chip from operating in an undervoltage state and causing performance degradation or damage;

[0027] Overcurrent protection circuit: When it detects that the output current exceeds the set maximum value, it quickly takes measures to limit the current, such as turning off the power MOSFET or adjusting the duty cycle of the PWM signal to protect the chip and external circuits from overcurrent damage;

[0028] The gate drive circuit amplifies and shapes the control signal generated by the control logic module, providing drive current and voltage to the gate of the power MOSFET, enabling the power MOSFET to respond quickly and accurately to the control signal and achieve efficient rectification. It usually has high drive capability and can meet the drive requirements of MOSFETs of different types and specifications;

[0029] Digital communication interfaces, such as SPI and I2C, are used to communicate with other chips or microcontrollers. Through digital communication interfaces, the synchronous rectifier controller can receive external control instructions and parameter settings, and at the same time feed back its own operating status and related information to external devices, enabling more complex power management functions and system-level collaborative control.

[0030] The self-powered unit can obtain energy from the input power supply or output power supply through internal circuits to provide power for the control chip itself, reducing dependence on external auxiliary power supply and improving system integration and reliability. For example, by setting an auxiliary winding on the secondary winding of the transformer, a stable power supply voltage is provided for the chip;

[0031] The present invention uses a control chip composed of an input module, a control logic module, an output module, a protection circuit module, a drive circuit module, a communication interface module, and a self-powered circuit module, and replaces traditional rectifier diodes with power MOSFETs with extremely low on-resistance, thereby greatly reducing conduction losses in the rectification process. In high-frequency, high-current power conversion applications, the power supply efficiency can be significantly improved, energy waste can be effectively reduced, and equipment operating costs can be reduced. At the same time, through a precise control algorithm, the synchronous rectification controller can effectively reduce the ripple of the output voltage, improve the stability and accuracy of the output voltage, provide a more stable and pure power supply for the load, and help improve the performance and life of the load equipment.

[0032] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A high-performance secondary-side synchronous rectification controller with built-in MOS, characterized in that: The control chip includes an input module, a control logic module, an output module, a protection circuit module, a drive circuit module, a communication interface module, and a self-powered circuit module. The input module is connected to the control logic module, the control logic module is connected to the output module, the output module is connected to the protection circuit module, the protection circuit module is connected to the drive circuit module, the drive circuit module is connected to the communication interface module, and the communication interface module is connected to the self-powered circuit module. The input module includes a voltage detection unit and a current detection unit, and the voltage detection unit is connected to the current detection unit. The control logic module includes a logic A control unit, a PWM generation unit, and a dead time control unit, wherein the logic control unit is connected to the PWM generation unit, and the PWM generation unit is connected to the dead time control unit; the output module includes a drive circuit and a power MOSFET, and the drive circuit is connected to the power MOSFET; the protection circuit module includes an over-temperature protection circuit, an under-voltage protection circuit, and an over-current protection circuit, and the over-temperature protection circuit is connected to the under-voltage protection circuit, and the under-voltage protection circuit is connected to the over-current protection circuit; the drive circuit module includes a gate drive circuit; the communication interface module includes a digital communication interface; and the self-powered circuit module includes a self-powered unit.

2. The high-performance secondary-side synchronous rectification controller with built-in MOS according to claim 1, characterized in that: The voltage detection circuit is used to monitor the input voltage and provide voltage information to the control chip, enabling it to adjust the control strategy according to changes in the input voltage, ensuring that the chip operates within the appropriate voltage range and realizing overvoltage and undervoltage protection functions. The current detection circuit detects the input or output current of the power supply through various components such as sampling resistors or current transformers.

3. The high-performance secondary-side synchronous rectification controller with built-in MOS according to claim 1, characterized in that: The logic control unit generates a control signal to drive the output module based on the voltage and current information provided by the input module, as well as internal preset parameters and algorithms, to achieve precise control of the synchronous rectification process. The PWM generation unit produces a pulse width modulation signal to control the on and off time of the power MOSFET. The dead time control unit is responsible for setting the dead time between the main switch and the synchronous rectification switch drive signal to avoid cross conduction of the MOSFET.

4. The high-performance secondary-side synchronous rectification controller with built-in MOS according to claim 1, characterized in that: The drive circuit amplifies and shapes the control signal generated by the control module, providing sufficient drive current and voltage for the power MOSFET, ensuring that the power MOSFET can respond to the control signal quickly and accurately; the power MOSFET is the key executive element of the synchronous rectification control chip.

5. The high-performance secondary-side synchronous rectification controller with built-in MOS according to claim 1, characterized in that: The over-temperature protection circuit monitors the temperature inside or outside the control chip and triggers the protection mechanism when the temperature exceeds a set threshold.

6. The high-performance secondary-side synchronous rectification controller with built-in MOS according to claim 1, characterized in that: The undervoltage protection circuit starts undervoltage protection when the input voltage or the supply voltage of the chip is lower than a certain value, causing the chip to enter a low power consumption mode or stop working.

7. The high-performance secondary-side synchronous rectification controller with built-in MOS according to claim 1, characterized in that: The overcurrent protection circuit quickly takes measures to limit the current when it detects that the output current exceeds the set maximum value.

8. The high-performance secondary-side synchronous rectification controller with built-in MOS according to claim 1, characterized in that: The gate drive circuit amplifies and shapes the control signal generated by the control logic module, provides drive current and voltage to the gate of the power MOSFET, and enables the power MOSFET to respond to the control signal quickly and accurately.

9. The high-performance secondary-side synchronous rectification controller with built-in MOS according to claim 1, characterized in that: The digital communication interface is used to communicate with other chips or microcontrollers. Through the digital communication interface, the synchronous rectification controller can receive external control instructions and parameter settings, and at the same time feed back its own working status and related information to external devices.

10. The high-performance secondary-side synchronous rectification controller with built-in MOS according to claim 1, characterized in that: The self-powered unit can obtain energy from the input power supply or the output power supply through the internal circuit to provide power for the operation of the control chip itself.

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