Power supply device and totem pole pfc circuit control method

Abstract

The application discloses a power supply device and a totem column PFC circuit control method. The power supply device comprises a totem column power factor correction (PFC) circuit and a control device. The totem column PFC circuit comprises a first switch tube and a second switch tube. The control device comprises a controller and a dead zone detection circuit. The dead zone detection circuit comprises a detection capacitor and a detection resistor. The first end of the detection capacitor is connected with a first reference point. The second end of the detection capacitor is connected with the first end of the detection resistor. The second end of the detection resistor is grounded. The controller generates a first dead zone control signal and a second dead zone control signal according to the voltage of the detection resistor and the positive and negative polarity of the voltage input by an alternating current input source. The controller controls the switching state of the first switch tube and the switching state of the second switch tube according to the first dead zone control signal and the second dead zone control signal. Based on the above structure, the switch tube in the totem column circuit can be provided with a suitable dead zone time, so that the totem column circuit obtains an optimal control effect.

Description

Technical Field

[0001] This application relates to the field of electronic power converters, and in particular to a power supply device and a totem pole PFC circuit control method. Background Technology

[0002] Traditional PFC circuits consist of two stages: a rectifier bridge and a boost PFC circuit. The large number of conducting components in traditional PFC circuits leads to reduced efficiency. In contrast, totem-pole PFC circuits achieve both rectification and PFC functions with only one conducting stage, thus reducing the number of conducting components and improving efficiency.

[0003] Figure 1A This is a schematic diagram of a totem pole PFC circuit structure, as shown below. Figure 1A As shown, the totem pole PFC circuit consists of an AC input source, an inductor L, four switching devices S1~S4, and an output filter capacitor C. OUT The load composition is as follows: S1 and S2 can be metal-oxide-semiconductor field-effect transistors (MOSFETs) or insulated-gate bipolar transistors (IGBTs) made of materials such as silicon (Si), silicon carbide (SiC), or gallium nitride (GaN), while S3 and S4 can be MOSFETs, IGBTs, or diodes made of materials such as Si, SiC, or GaN.

[0004] The inductor current is controlled by controlling the switching states of S1 and S2 in the totem pole PFC circuit, thereby achieving control of the entire totem pole PFC circuit. Figure 1B The operating states of the totem-pole PFC circuit under different switching conditions are shown. Figure 1B a) and b) in the text refer to the AC input source V AC This is a schematic diagram of the clock operation. At this time, S3 is open, S4 is on, S2 is on as the main switch to charge inductor L, and S1 is on as the secondary switch to discharge inductor L. Figure 1B c) and d) in the equation refer to the AC input source V. AC The diagram shows the operation when the value is negative. At this time, S3 is on, S4 is off, S1 is on as the main switch to charge the inductor, and S2 is on as the secondary switch to discharge the inductor.

[0005] During the alternating conduction of S1 and S2, if S1 and S2 conduct simultaneously (bridge arm shoot-through), a large short-circuit current will be generated, leading to device damage. Therefore, to prevent shoot-through while meeting the requirements of soft switching, an interval time (also known as dead time) needs to be set between the alternating conduction of S1 and S2 to avoid shoot-through. For soft switching, after S1 is turned off, the voltage at the series connection point SW1 of S1 and S2 can theoretically drop to 0V before S2 is turned on, thus achieving zero-voltage switching of S2. (See also...) Figure 1C As shown in (a), setting the dead time too small can cause a hard-on problem between S1 and S2. See also... Figure 1C As shown in (b), setting the dead time too large will lead to increased power loss, reduced power utilization, and will also cause hard turn-on problems.

[0006] Therefore, the dead time must be set to a suitable value to achieve optimal control performance for the totem-pole PFC circuit. However, due to the AC input source V of the totem-pole PFC circuit... AC Since the voltage is sinusoidal AC, the rate and duration of voltage change at point SW1 vary at different times within the dead time. Current technology cannot achieve optimal control of the totem-pole PFC circuit. Therefore, finding a way to achieve optimal control of the totem-pole PFC circuit is a pressing issue for those skilled in the art. Summary of the Invention

[0007] This application provides a power supply device and a totem pole PFC circuit control method for optimal control of the totem pole PFC circuit.

[0008] Firstly, this application provides a power supply device comprising: a totem-pole power factor correction (PFC) circuit and a control device. The totem-pole PFC circuit includes a first switching transistor and a second switching transistor. The source and drain of the first and second switching transistors are connected to a first reference point. A first input terminal of an AC input source is connected to the first reference point via an inductor. The control device includes a controller and a dead-time detection circuit. The dead-time detection circuit includes a detection capacitor and a detection resistor. A first terminal of the detection capacitor is connected to the first reference point, and a second terminal of the detection capacitor is connected to a first terminal of the detection resistor. The second terminal of the detection resistor is grounded. The controller generates a first dead-time control signal and a second dead-time control signal based on the voltage across the detection resistor and the polarity of the voltage input from the AC input source. It controls the switching state of the first switching transistor based on the first dead-time control signal and the switching state of the second switching transistor based on the second dead-time control signal. Based on this structure, the power supply device can set an appropriate dead time for the switching transistors in the totem-pole PFC circuit, thereby enabling the totem-pole PFC circuit to achieve optimal control performance.

[0009] In some possible implementations, the control device further includes an AC input source polarity detection circuit; this AC input source polarity detection circuit is used to detect the positive or negative polarity of the voltage input to the AC input source. By detecting the positive or negative polarity of the voltage input to the AC input source, a first dead-time control signal and a second dead-time control signal can be determined based on the polarity of the voltage input to the AC input source, and then the switching states of the first and second switching transistors can be controlled using the first and second dead-time control signals.

[0010] In some possible implementations, the AC input source polarity detection circuit is specifically used to: measure a first voltage at a first input terminal of the AC input source and a second voltage at a second input terminal of the AC input source, and calculate the voltage difference between the first voltage and the second voltage; when the voltage difference is greater than a first preset voltage, determine that the voltage input to the AC input source is positive, and the first preset voltage is not less than 0; when the voltage difference is less than a second preset voltage, determine that the voltage input to the AC input source is negative, and the second preset voltage is not greater than 0. By detecting the first voltage at the first input terminal of the AC input source and the second voltage at the second input terminal of the AC input source, the polarity of the voltage input to the AC input source can be determined based on the voltage difference between the first voltage and the second voltage.

[0011] In some possible implementations, the control device further includes a voltage measurement module for measuring the voltage across the detection resistor. The voltage measurement module detects the voltage across the resistor, and by using this voltage, the slope of the voltage change at the first reference point can be indirectly determined. This allows for the detection of whether the inductor on the totem-pole PFC circuit crosses zero, as well as the peak and valley voltage signals at the first reference point. Based on these parameters, a first dead-time control signal and a second dead-time control signal are determined, and these signals are used to control the switching states of the first and second switching transistors.

[0012] In some possible implementations, the controller is specifically configured to: generate an indication signal based on the voltage across the sensing resistor and the polarity of the voltage input from the AC input source; and generate a first dead-time control signal and a second dead-time control signal based on the indication signal and the polarity of the voltage input from the AC input source. The indication signal is used to indicate the dead-time state of the first and second switching transistors, and includes both the first and second indication signals. By acquiring the voltage across the sensing resistor, it can be determined whether the voltage across the sensing resistor is at a peak or a valley value, thereby generating the indication signal. For example, when the polarity signal indicates that the voltage input from the AC input source is positive and the voltage across the sensing resistor is at a valley value, the indication signal may include a first indication signal indicating that the first switching transistor is in a dead-time state; while when the voltage across the sensing resistor is at a peak value, the indication signal may include a second indication signal indicating that the second switching transistor is in a dead-time state.

[0013] In some possible implementations, when the voltage input to the AC input source is determined to be positive and the voltage across the sensing resistor is less than a first threshold, the second indication signal is used to indicate that the first switch is in a dead-zone state; when the voltage input to the AC input source is determined to be positive and the voltage across the sensing resistor is greater than a second threshold, the first indication signal is used to indicate that the second switch is in a dead-zone state; when the voltage input to the AC input source is determined to be negative and the voltage across the sensing resistor is less than a third threshold, the first indication signal is used to indicate that the first switch is in a dead-zone state; and when the voltage input to the AC input source is determined to be negative and the voltage across the sensing resistor is greater than a fourth threshold, the second indication signal is used to indicate that the second switch is in a dead-zone state; wherein the first threshold is less than the second threshold, and the third threshold is less than the fourth threshold. Different indication signals can be used to indicate whether the first and second switches are in a dead-zone state.

[0014] In some possible implementations, the controller specifically includes: a first multiplexer switch, a second multiplexer switch, a first comparator, a second comparator, and an inverter; the output terminal of the first multiplexer switch is connected to the negative terminal of the first comparator, and the output terminal of the second multiplexer switch is connected to the negative terminal of the second comparator; the output terminal of the second comparator is connected to the inverter; the first input terminal of the first multiplexer switch is used to input a fourth threshold voltage, and the second input terminal of the first multiplexer switch is used to input a first threshold voltage; the first input terminal of the second multiplexer switch is used to input a third threshold voltage, and the second input terminal of the second multiplexer switch is used to input a second threshold voltage; The positive terminal of the first comparator is used to receive the voltage of the detection resistor, and the positive terminal of the second comparator is also used to receive the voltage of the detection resistor. When the voltage input from the AC input source is determined to be positive, the controller controls the first multiplexer switch to connect the first input terminal to the output terminal, and the controller controls the second multiplexer switch to connect the first input terminal to the output terminal. When the voltage input from the AC input source is determined to be negative, the controller controls the first multiplexer switch to connect the second input terminal to the output terminal, and the controller controls the second multiplexer switch to connect the second input terminal to the output terminal. The first comparator is used to output a first indication signal; the inverter is used to output a second indication signal.

[0015] In some possible implementations, the controller is specifically configured to: when it is determined that the voltage input to the AC input source is positive, generate a first dead-zone control signal according to a first indication signal and generate a second dead-zone control signal according to a second indication signal; when it is determined that the voltage input to the AC input source is negative, generate a first dead-zone control signal according to a second indication signal and generate a second dead-zone control signal according to the first indication signal.

[0016] In some possible implementations, the control device further includes: a first pulse generation circuit, used to generate a first pulse signal and a second pulse signal; the first pulse signal is used to generate a first dead-time control signal, and the second pulse signal is used to generate a second dead-time control signal; the controller is further used to: when it is determined that the voltage input to the AC input source is positive, generate the first dead-time control signal according to a first indication signal and the first pulse signal, and generate the second dead-time control signal according to a second indication signal and the second pulse signal; when it is determined that the voltage input to the AC input source is negative, generate the first dead-time control signal according to the second indication signal and the first pulse signal, and generate the second dead-time control signal according to the first indication signal and the second pulse signal. The control device may also include sampling modules such as an output voltage sampling module and an inductor current sampling module. The output voltage sampling module is used to send the output voltage value output to the load to the first pulse generation circuit, and the inductor current sampling module is used to send the current value of the inductor on the totem-pole PFC circuit to the first pulse generation circuit. The first pulse generation circuit can generate the first pulse signal and the second pulse signal according to the output voltage value and the inductor current value. For example, when the output voltage from the output to the load is detected to be lower than the voltage threshold, the first pulse generation circuit can increase the duty cycle of the first pulse signal and the second pulse signal so that the totem pole PFC circuit outputs a stable voltage.

[0017] In some possible implementations, the control device further includes: a frequency detection module and a switching module; the frequency detection module is used to detect a first signal frequency and a second signal frequency, the first signal frequency being the frequency of a first pulse signal and the second signal frequency being the frequency of a second pulse signal; the switching module is used to control the switching state of a first switching transistor according to the first signal frequency and to control the switching state of a second switching transistor according to the second signal frequency. Using the above structure, the switching losses of the switching transistors can be reduced.

[0018] In some possible implementations, the totem-pole PFC circuit further includes: a first diode and a second diode, the anode of the first diode and the cathode of the second diode being connected to the second input terminal of the AC input source through a second reference point; the anode of the second diode is grounded. In some possible implementations, the totem-pole PFC circuit further includes: a third switch and a fourth switch, the source and drain of the third switch and the fourth switch being connected to the second input terminal of the AC input source through a second reference point; the drain of the third switch is connected to the drain of the first switch; the source of the fourth switch is grounded. The control device further includes: a second pulse generation circuit for generating a third pulse signal and a fourth pulse signal; the controller is also used to: control the switching state of the third switch according to the third pulse signal, and control the switching state of the fourth switch according to the fourth pulse signal. This enables synchronous rectification of the totem-pole PFC circuit.

[0019] When a hard turn-on occurs or the inductor current in the totem-pole PFC circuit is large, the voltage at the first reference point changes rapidly, resulting in a large current across the sensing capacitor and consequently a large voltage across the sensing resistor. This voltage may even exceed the withstand voltage threshold of the subsequent circuit, potentially damaging it. Therefore, in some possible implementations, the control device further includes a protection circuit comprising a first Zener diode and a second Zener diode, connected in parallel with the sensing resistor. The positive terminals of the first and second Zener diodes are connected, and the negative terminal of the second Zener diode is grounded. Using the first and second Zener diodes, the maximum voltage across the sensing resistor can be effectively limited, thus effectively protecting the subsequent circuit. Furthermore, the maximum voltage across the sensing resistor does not affect the control of the dead time.

[0020] Secondly, this application provides a totem-pole PFC circuit control method. A control device is used to control the totem-pole PFC circuit, which includes a first switching transistor and a second switching transistor. The source and drain of the first and second switching transistors are connected to a first reference point. The first input terminal of an AC input source is connected to the first reference point via an inductor. The control device includes a controller and a dead-time detection circuit. The dead-time detection circuit includes a detection capacitor and a detection resistor. The first terminal of the detection capacitor is connected to the first reference point, and the second terminal of the detection capacitor is connected to the first terminal of the detection resistor. The second terminal of the detection resistor is grounded. The totem-pole PFC circuit control method is applied to the controller. The method includes: generating a first dead-time control signal and a second dead-time control signal based on the voltage of the detection resistor and the polarity of the voltage input from the AC input source; controlling the switching state of the first switching transistor based on the first dead-time control signal; and controlling the switching state of the second switching transistor based on the second dead-time control signal. The technical effects of the corresponding solution in the second aspect can be referred to the technical effects obtainable by the corresponding solution in the first aspect; repeated details are not elaborated here.

[0021] These or other aspects of this application will become more apparent from the description of the following embodiments. Attached Figure Description

[0022] Figure 1A This is a schematic diagram of the totem pole PFC circuit structure; Figure 1B A schematic diagram of the working state of the totem pole PFC circuit under different switching states; Figure 1C This is a waveform diagram of a totem pole PFC circuit. Figure 2 This is a schematic diagram of a PFC circuit for controlling totem poles; Figure 3 This is a schematic diagram of another type of PFC circuit for controlling totem poles; Figure 4 This is a schematic diagram of the structure of a power supply device; Figure 5 This is a waveform diagram of the dead zone detection circuit; Figure 6A A schematic diagram of a control device including an AC input source polarity detection circuit; Figure 6B This is a schematic diagram of an AC input source polarity detection circuit; Figure 6C A waveform diagram of an AC input source polarity detection circuit; Figure 7 This is a schematic diagram of a control device that includes a voltage measurement module; Figure 8A This is a schematic diagram of the structure of a controller; Figure 8B This is a waveform diagram of the controller; Figure 9 A schematic diagram of a control device including a first pulse generation circuit; Figure 10A This is a schematic diagram of a totem-pole PFC circuit for synchronous rectification. Figure 10B A schematic diagram of a control device including a second pulse generation circuit; Figure 11 This is a schematic diagram of another control device; Figure 12 This is a schematic diagram of a control device that includes a protection circuit. Figures 13-16 This is a schematic diagram of the working waveforms of a totem pole PFC circuit. Detailed Implementation

[0023] The following explanations will first clarify some of the terms used in the embodiments of this application, so that those skilled in the art can easily understand them.

[0024] (1) PFC circuit: A circuit used for power factor correction. The rectifier bridge of a conventional rectifier filter circuit only conducts when the input sinusoidal voltage is close to its peak value. The input current will have a serious non-sinusoidal characteristic, resulting in a large number of harmonic current components. At the same time, the harmonic current components may also interfere with other electrical equipment. The PFC circuit shapes the input AC current into a sinusoidal wave that is approximately the same as and in phase with the input voltage, so that the input power is as close as possible to 1.

[0025] Commonly used PFC circuits are mostly based on the Boost converter topology. Based on the different characteristics of the Boost converter topology in different operating modes (intermittent conduction mode / critical conduction mode / continuous conduction mode), there are various control methods corresponding to these characteristics.

[0026] (2) Totem PFC Circuit: Traditional PFC circuits consist of a rectifier bridge and a Boost PFC circuit, forming a two-stage circuit, hence the name "bridged PFC circuit." To further improve efficiency, bridgeless PFC combines the rectifier bridge and PFC circuit into a single-stage circuit, eliminating the losses of the rectifier bridge section while simultaneously achieving rectification and power factor correction; therefore, it is called a bridgeless PFC circuit. The totem PFC circuit is the most efficient topology among bridgeless PFC circuits and is also simpler than other bridgeless PFC circuits; it can also be called a totem pole bridgeless PFC circuit.

[0027] (3) Dead time: After the upper half bridge of the PFC circuit is turned off, the lower half bridge is turned on after a certain period of time, or after the lower half bridge is turned off, the upper half bridge is turned on after a certain period of time, so as to prevent the bridge arm from shoot-through. The above delay time is the dead time. During this period of time, the switches of the upper and lower bridges are turned off.

[0028] It should be noted that in the description of this application, "at least one" refers to one or more, where "multiple" refers to two or more. Therefore, in the embodiments of this application, "multiple" can also be understood as "at least two". "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. Additionally, the character " / ", unless otherwise specified, generally indicates that the preceding and following related objects have an "or" relationship. Furthermore, it should be understood that in the description of this application, words such as "first" and "second" are used only for descriptive purposes and should not be construed as indicating or implying relative importance or order.

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the application will now be described in further detail with reference to the accompanying drawings.

[0030] Setting the dead time too small in a totem-pole PFC circuit can lead to hard turn-on issues, while setting it too large can increase power loss, reduce power utilization, and also cause hard turn-on problems. Therefore, setting an appropriate dead time for the switching transistors in the totem-pole PFC circuit is essential to achieve optimal control performance.

[0031] In some possible implementations, see [reference] Figure 2 As shown, current transformers CT1 and CT2 can be connected in series with S1 and S2 in the totem-pole PFC circuit to detect the current flowing through the S1 and S2 switches. When the current transformer detects a change in the polarity of the current on its corresponding switch, it sends the polarity change message to the switch control module. After a fixed dead time, the switch control module uses a PWM signal to control the next switch to turn on, thus achieving zero-voltage turn-on or valley-voltage turn-on of the switches (S1 and S2). However, current transformers are expensive and bulky, and after the current transformer detects a change in current polarity, a fixed dead time is required before the next switch can be turned on. Therefore, the fixed dead time cannot adapt to all operating points, thus preventing the totem-pole PFC circuit from achieving optimal control performance.

[0032] In other possible implementations, see [reference] Figure 3 As shown, an auxiliary winding or resistor is added to inductor L to detect the voltage across inductor L. When inductor L is charging and the current rises, the voltage across inductor L is positive; when inductor L is discharging and the current falls, the voltage across inductor L is negative. Therefore, the reversal of the voltage across inductor L can be detected at the two current points of maximum and minimum current. When the current zero-crossing detection circuit detects the voltage reversal signal, the switching control module, after a fixed dead time, controls the next switching transistor to conduct via a PWM signal, thereby achieving zero-voltage conduction or valley-voltage turn-on of the switching transistors (S1 and S2). Similarly, after the current zero-crossing detection circuit detects the voltage reversal signal, a fixed dead time always passes before the next switching transistor can be turned on. Therefore, using a fixed dead time still cannot adapt to all operating points, thus failing to achieve optimal control performance for the totem-pole PFC circuit.

[0033] Continue reading Figure 1A As shown, due to the AC input source V of the totem pole PFC circuit AC Since the voltage is sinusoidal AC, the rate and duration of voltage change at point SW1 vary at different times within the dead time. Therefore, if the control device uses a fixed dead time, optimal control performance cannot be achieved. In view of this, how to achieve optimal control of the totem-pole PFC circuit is a problem that urgently needs to be solved by those skilled in the art.

[0034] This application provides a power supply device including a control device and a totem-pole PFC circuit. The control device can detect the voltage polarity of the AC input source to the totem-pole PFC circuit and the voltage of a first reference point in the totem-pole PFC circuit. The control device can generate a dead-time control signal based on the voltage of the first reference point and the voltage polarity of the AC input source voltage. The first reference point is the connection point between the source of the upper bridge arm switch and the drain of the lower bridge arm switch in the totem-pole PFC circuit. The control device in the power supply can control the switching states of the upper bridge arm switch and the lower bridge arm switch in the totem-pole PFC circuit according to the dead-time control signal, so that the power supply can perform optimal control of the totem-pole PFC circuit.

[0035] Figure 4 A power supply device 400 is provided in the embodiments of this application. The power supply device 400 includes a totem pole power factor correction (PFC) circuit and a control device 401. The totem pole PFC circuit includes a first switching transistor 402 and a second switching transistor 403. The source of the first switching transistor 402 and the drain of the second switching transistor 403 are connected to a first reference point. The first input terminal of the AC input source is connected to the first reference point through an inductor.

[0036] The control device 401 includes a controller 404 and a dead zone detection circuit 405. The dead zone detection circuit 405 includes a detection capacitor 4051 and a detection resistor 4052. The first end of the detection capacitor 4051 is connected to the first reference point, the second end of the detection capacitor 4051 is connected to the first end of the detection resistor 4052, and the second end of the detection resistor 4052 is grounded.

[0037] The controller 404 is configured to generate a first dead-zone control signal and a second dead-zone control signal based on the voltage of the detection resistor 4052 and the polarity of the voltage input from the AC input source, and to control the switching state of the first switch transistor 402 based on the first dead-zone control signal and the switching state of the second switch transistor 403 based on the second dead-zone control signal.

[0038] Optionally, the power supply device 400 can be an alternating current to direct current (AC-DC) converter. The power supply device 400 can control the switching states of the first switch 402 and the second switch 403 in the totem pole PFC circuit according to the dead-time control signal, thereby enabling the power supply device 400 to have optimal control over the totem pole PFC circuit.

[0039] The controller 404 can detect the polarity of the voltage input to the AC input source. For example, the polarity of the current AC input voltage can be determined by acquiring the voltage difference between the voltage at the first and second input terminals of the AC input source. Alternatively, the polarity of the AC input voltage can also be determined by directly measuring the input voltage of the AC input source.

[0040] The detection capacitor 4051 and the detection resistor 4052 can form a resistor-capacitor (RC) circuit. Generally, the value of the detection resistor 4052 can be determined by the sampling accuracy, so that the voltage across the detection resistor 4052 will not be too high and damage the subsequent circuit.

[0041] Optionally, during the switching transition between the first switch 402 and the second switch 403, the voltage at the first reference point will increase or decrease, and the voltage change at the first reference point will generate a current i across the detection capacitor 4051. d And the current i d After flowing through the detection resistor 4052, a voltage V is generated across the detection resistor 4052. DT And measure the voltage V across the detection resistor 4052. DT Through V DTThe slope of the voltage change at the first reference point can be determined, thereby enabling the detection of whether the inductor on the totem pole PFC circuit crosses zero, as well as the peak voltage signal and valley voltage signal at the first reference point, etc.

[0042] See Figure 5 As shown, Figure 5 This is a waveform diagram of the dead-time detection circuit. During the dead-time period when the first switch 402 is off and the second switch 403 is on, the voltage V at the first reference point is... 第一参考点 This will reduce V during the dead time when the second switch 403 turns off and the first switch 402 turns on. 第一参考点 This will improve performance. Specifically, the detection capacitor 4051 is C. d The detection resistor 4052 is R d Because a voltage change occurs at the first reference point, it will occur at C. d Current i is generated on d , Continue reading Figure 5 As shown, i d Flowing through R d The voltage across the detection resistor 4052 that is subsequently generated is V. DT ,but via V DT The value of V can determine 第一参考点 The slope of the voltage change.

[0043] The voltage change slope of the first reference point can be indirectly determined by obtaining the voltage of the detection resistor 4052. The magnitude of the voltage on the detection resistor 4052 is determined by the capacitance value of the detection capacitor 4051 and the resistance value of the detection resistor 4052 in the dead zone detection circuit 405. Since the dead zone detection circuit 405 is connected in parallel to the first reference point, the dead zone detection circuit 405 does not affect the normal operation of the totem pole PFC circuit, and therefore will not cause efficiency loss in the totem pole PFC circuit.

[0044] After determining the voltage across the detection resistor 4052, a first dead-time control signal and a second dead-time control signal can be generated based on the voltage polarity of the AC input source and the voltage across the detection resistor 4052, thereby controlling the switching states of the first switch 402 and the second switch 403. Furthermore, the controller 404 can also be a processor, a central processing unit (CPU), a system-on-chip (SoC), an electronic control unit (ECU), a digital signal processing unit (DSP), an application-specific integrated circuit (ASIC), a programmable logic device (PLD), a field-programmable gate array (FPGA), or other transistor logic devices, hardware components, or any combination thereof. The aforementioned processor can also be a combination that implements computational functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc., which will not be listed in detail in this embodiment.

[0045] The following provides further illustrative examples of some specific structures of the control device 401 provided in this application.

[0046] In some possible implementations, see [reference] Figure 6A As shown, the control device 401 further includes: an AC input source polarity detection circuit 406; the AC input source polarity detection circuit 406 is used to detect the positive and negative polarities of the voltage input by the AC input source. The AC input source polarity detection circuit 406 can be connected to both ends of the AC input source, thereby determining the positive and negative polarities of the AC input voltage based on the voltage at the first input terminal and the voltage at the second input terminal. For example, the positive and negative polarities of the current AC input voltage can be determined by obtaining the voltage difference between the voltage at the first input terminal and the voltage at the second input terminal of the AC input source.

[0047] In some possible implementations, the AC input source polarity detection circuit 406 is specifically used to: measure a first voltage at a first input terminal of the AC input source and a second voltage at a second input terminal of the AC input source, and calculate the voltage difference between the first voltage and the second voltage; when the voltage difference is greater than a first preset voltage, determine that the voltage input by the AC input source is positive, and the first preset voltage is not less than 0; when the voltage difference is less than a second preset voltage, determine that the voltage input by the AC input source is negative, and the second preset voltage is not greater than 0. Wherein, by detecting the first voltage at the first input terminal of the AC input source and the second voltage at the second input terminal of the AC input source, and by outputting a polarity signal, the controller 404 can determine the polarity of the voltage input by the AC input source using a polarity signal.

[0048] For example Figure 6B As shown, the AC input source polarity detection circuit 406 may specifically include an AC voltage sampling circuit and an AC polarity determination circuit. The AC voltage sampling circuit can be a subtractor, used to calculate the difference between the first voltage at the first input terminal of the AC input source and the second voltage at the second input terminal of the AC input source, thereby inputting the voltage difference to the AC polarity determination circuit. For example, the AC polarity determination circuit can be a comparator, thereby determining the polarity of the AC input source. Figure 6C The waveforms of the input voltage, voltage difference, and polarity signal of the AC input source are shown below. Figure 6C As shown, when the input voltage of the AC input source is positive, the voltage difference is greater than 0, and a high-level signal indicating positive polarity is output. Conversely, when the input voltage of the AC input source is negative, the voltage difference is less than 0, and a low-level signal indicating negative polarity is output.

[0049] In some possible implementations, see [reference] Figure 7 As shown, the control device 401 further includes a voltage measurement module 407, which is used to measure the voltage of the detection resistor. In some possible embodiments, the controller 404 is specifically used to: generate an indication signal based on the voltage of the detection resistor 4052 and the polarity of the voltage input from the AC input source; and generate a first dead-zone control signal and a second dead-zone control signal based on the indication signal and the polarity of the voltage input from the AC input source. The indication signal is used to indicate the dead-zone state of the first switch 402 and the second switch 403, and the indication signal includes a first indication signal and a second indication signal.

[0050] In some possible implementations, when it is determined that the voltage input to the AC input source is positive and the voltage of the detection resistor 4052 is less than a first threshold, the second indication signal is used to indicate that the first switch 402 is in a dead zone state; when it is determined that the voltage input to the AC input source is positive and the voltage of the detection resistor 4052 is greater than a second threshold, the first indication signal is used to indicate that the second switch 403 is in a dead zone state; when it is determined that the voltage input to the AC input source is negative and the voltage of the detection resistor 4052 is less than a third threshold, the first indication signal is used to indicate that the first switch 402 is in a dead zone state; when it is determined that the voltage input to the AC input source is negative and the voltage of the detection resistor 4052 is greater than a fourth threshold, the second indication signal is used to indicate that the second switch 403 is in a dead zone state; wherein the first threshold is less than the second threshold, and the third threshold is less than the fourth threshold.

[0051] In some possible implementations, see [reference] Figure 8A As shown, the controller 404 specifically includes: a first multiplexer 4081, a second multiplexer 4082, a first comparator 4083, a second comparator 4084, and an inverter 4085. The output terminal of the first multiplexer 4081 is connected to the negative terminal of the first comparator 4083, and the output terminal of the second multiplexer 4082 is connected to the negative terminal of the second comparator 4084. The output terminal of the second comparator 4084 is connected to the inverter 4085. The first input terminal of the first multiplexer 4081 is used to input the voltage of the fourth threshold, and the second input terminal of the first multiplexer 4081 is used to input the voltage of the first threshold. The first input terminal of the second multiplexer 4082 is used to input the voltage of the third threshold, and the second input terminal of the second multiplexer 4082 is used to input the voltage of the second threshold. The positive terminal of the first comparator 4083 is used to receive the voltage of the detection resistor 4052, and the positive terminal of the second comparator 4084 is used to receive the voltage of the detection resistor 4052.

[0052] When the voltage input to the AC input source is determined to be positive, the controller 404 controls the first multiplexer 4081 to connect the first input terminal to the output terminal, and the controller 404 controls the second multiplexer 4082 to connect the first input terminal to the output terminal; when the voltage input to the AC input source is determined to be negative, the controller 404 controls the first multiplexer 4081 to connect the second input terminal to the output terminal, and the controller 404 controls the second multiplexer 4082 to connect the second input terminal to the output terminal; the first comparator 4083 is used to output the first indication signal; the inverter 4085 is used to output the second indication signal.

[0053] Figure 8B This is a waveform diagram of the controller. (Example) Figure 8B As shown, the first threshold is less than the second threshold, and the third threshold is less than the fourth threshold. When the polarity signal is a positive polarity signal (high level), both the first and second indicator signals are low level signals. When the voltage across the detection resistor 4052 is greater than the second threshold, the first indicator signal switches to a high level signal. When the voltage across the detection resistor 4052 is less than the first threshold, the second indicator signal switches to a high level signal. Conversely, when the polarity signal is a negative polarity signal (low level), both the first and second indicator signals are high level signals. When the voltage across the detection resistor 4052 is less than the third threshold, the first indicator signal switches to a low level signal. When the voltage across the detection resistor 4052 is greater than the fourth threshold, the second indicator signal switches to a high level signal.

[0054] In some possible implementations, the controller 404 may specifically be used to: when it is determined that the voltage input to the AC input source is positive, generate a first dead-zone control signal according to the first indication signal and generate a second dead-zone control signal according to the second indication signal; when it is determined that the voltage input to the AC input source is negative, generate the first dead-zone control signal according to the second indication signal and generate a second dead-zone control signal according to the first indication signal.

[0055] In some possible implementations, see [reference] Figure 9As shown, the control device 401 may further include: a first pulse generation circuit 409, which generates a first pulse signal and a second pulse signal; the first pulse signal generates a first dead-time control signal, and the second pulse signal generates a second dead-time control signal; the controller 404 is further configured to: when it is determined that the voltage input to the AC input source is positive, generate the first dead-time control signal according to the first indication signal and the first pulse signal, and generate the second dead-time control signal according to the second indication signal and the second pulse signal; when it is determined that the voltage input to the AC input source is negative, generate the first dead-time control signal according to the second indication signal and the first pulse signal, and generate the second dead-time control signal according to the first indication signal and the second pulse signal. For example, the first pulse signal and the second pulse signal may be PWM pulse modulation signals.

[0056] Optionally, the control device 401 may further include sampling modules such as an output voltage sampling module and an inductor current sampling module. The output voltage sampling module sends the output voltage value to the load to the first pulse generation circuit 409. The inductor current sampling module sends the current value of the inductor on the totem pole PFC circuit to the first pulse generation circuit 409. The first pulse generation circuit 409 can generate the first pulse signal and the second pulse signal based on the output voltage value and the inductor current value.

[0057] In some possible implementations, the totem-pole PFC circuit may further include a first diode and a second diode, wherein the anode of the first diode and the cathode of the second diode are both connected to the second input terminal of the AC input source through a second reference point. The anode of the second diode is grounded.

[0058] In other possible implementations, to achieve synchronous rectification of the totem-pole PFC circuit, see [reference needed]. Figure 10A As shown, the totem pole PFC circuit further includes a third switch 4101 and a fourth switch 4102. The source of the third switch 4101 and the drain of the fourth switch 4102 are both connected to the second input terminal of the AC input source through a second reference point. The drain of the third switch 4101 is connected to the drain of the first switch 402, and the source of the fourth switch 4102 is grounded.

[0059] See Figure 10BAs shown, the control device 401 may further include a second pulse generation circuit 4103. The second pulse generation circuit 4103 is used to generate a third pulse signal and a fourth pulse signal. It controls the switching state of the third switch transistor 4101 according to the third pulse signal and controls the switching state of the fourth switch transistor 4102 according to the fourth pulse signal, thereby achieving synchronous rectification of the totem-pole PFC circuit.

[0060] Furthermore, according to the working principle of the totem-pole PFC circuit, as the load decreases, when the AC input source is in a low phase, the frequencies of the first pulse signal and the second pulse signal generated by the first pulse generation circuit 409 will continuously increase, resulting in greater switching losses. In some possible implementations, see [reference needed]. Figure 11 As shown, the control device 401 further includes: a frequency detection module 4111 and a switching module 4112; the frequency detection module 4111 is used to detect a first signal frequency and a second signal frequency, the first signal frequency being the frequency of the first pulse signal and the second signal frequency being the frequency of the second pulse signal; the switching module 4112 is used to control the switching state of the first switching transistor according to the first signal frequency and to control the switching state of the second switching transistor according to the second signal frequency.

[0061] The frequency detection module 4111 is used to detect a first signal frequency and a second signal frequency, wherein the first signal frequency is the frequency of the first pulse signal and the second signal frequency is the frequency of the second pulse signal. The switching module 4112 is used to control the switching state of the first switching transistor 402 according to the first signal frequency and to control the switching state of the second switching transistor 403 according to the second signal frequency. Optionally, if the first signal frequency is greater than a frequency threshold, the next cycle will not begin until a frequency less than the frequency threshold is detected; or if the second signal frequency is greater than a frequency threshold, the next cycle will not begin until a frequency less than the frequency threshold is detected.

[0062] When a hard turn-on occurs or the inductor current in the totem-pole PFC circuit is large, the voltage at the first reference point changes rapidly, resulting in a large current across the detection capacitor 4051 and consequently a large voltage across the detection resistor 4052. This voltage may even exceed the withstand voltage threshold of the subsequent circuit, damaging it. Therefore, in some possible implementations, see [reference needed]. Figure 12 As shown, the control device 401 may further include a protection circuit 412. The protection circuit 412 is connected in parallel with the detection resistor 4052.

[0063] In the protection circuit 412, the positive terminal of the first Zener diode 4121 is connected to the positive terminal of the second Zener diode 4122, and the negative terminal of the second Zener diode 4122 is grounded. By utilizing the first Zener diode 4121 and the second Zener diode 4122, the maximum voltage across the sensing resistor 4052 can be effectively limited, thereby effectively protecting the subsequent circuitry. Furthermore, the maximum voltage across the sensing resistor 4052 does not affect the control of the dead time.

[0064] Optionally, the control mode of the totem pole PFC circuit provided by the control device 401 in this application embodiment may specifically include: mode 1 to mode 4.

[0065] Mode 1: AC input source inputs positive voltage.

[0066] When the voltage input from the AC input source is determined to be positive, the polarity signal is a positive polarity signal. The first indication signal controls the dead time from the second switch 403 to the first switch 402, and the second indication signal controls the dead time from the first switch 402 to the second switch 403.

[0067] See Figure 13 As shown, at time t0, the second switch 403 is turned off, and the inductor current charges the parasitic capacitance of the second switch 403 and discharges the parasitic capacitance of the first switch 402, thus causing the voltage at the first reference point to rise. At time t1, the first indicator signal changes from 1 to 0, corresponding to the voltage at the first reference point rising to the level of V. out At the same time, the first switch 402 is turned on. When the first switch 402 is turned on, the voltage between the drain and source is 0, achieving zero-voltage turn-on. At time t2, the first switch 402 is turned off, the parasitic capacitance of the second switch 403 discharges, and the parasitic capacitance of the first switch 402 charges, thus the voltage at the first reference point drops. At time t3, the first indicator signal changes from 1 to 0, corresponding to the moment when the voltage at the first reference point drops to 0. At this time, the second switch 403 can be turned on in S2. When the second switch 403 is turned on, the voltage between the drain and source is 0, thus achieving zero-voltage turn-on.

[0068] Mode 2: AC input source inputs negative voltage.

[0069] When the voltage input from the AC input source is determined to be negative, the polarity signal is a negative polarity signal. The first indication signal controls the dead time from the first switch 402 to the second switch 403, and the second indication signal controls the dead time from the second switch 403 to the first switch 402.

[0070] See Figure 14As shown, at time t0, the first switch 402 is turned off, and the inductor current charges the parasitic capacitance of the first switch 402 and discharges the parasitic capacitance of the second switch 403, thus causing the voltage at the first reference point to drop. At time t1, the first indicator signal changes from 0 to 1, corresponding to the moment when the voltage at the first reference point drops to 0. At this time, the second switch 403 is turned on, and the drain-source voltage is 0 when the second switch 403 is turned on, achieving zero-voltage conduction. At time t2, the second switch 403 is turned off, the parasitic capacitance of the first switch 402 discharges, and the parasitic capacitance of the second switch 403 charges, thus causing the voltage at the first reference point to rise. At time t3, the second indicator signal changes from 0 to 1, corresponding to the voltage at the first reference point rising to the level of V. out At the same time, the first switch 402 is turned on. When the first switch 402 is turned on, the voltage between the drain and source is 0, thus achieving zero-voltage conduction.

[0071] Mode 3: The AC input source provides a positive voltage, and the frequency of the pulse signal is limited.

[0072] See Figure 15 As shown, the dead time control from the turn-off of the second switch 403 to the turn-on of the first switch 402 is the same as in mode 1. The difference in the dead time control from the turn-off of the first switch 402 to the turn-on of the second switch 403 is due to the frequency limitation of the pulse signal. At time t2, the first switch 402 is turned off. Then at time t3, the second indicator signal changes from 1 to 0. However, at this time, the first pulse signal and / or the second pulse signal are greater than the frequency threshold, thus subject to frequency limitation. To reduce switching losses, the second switch 403 cannot be turned on at time t3. Similarly, it cannot be turned on at time t4. At time t5, the second indicator signal changes from 1 to 0 again, and simultaneously satisfies the condition that the first pulse signal and / or the second pulse signal are not greater than the frequency threshold. At this time, the second switch 403 is turned on. When the second switch 403 is turned on, the voltage between its drain and source is 0, thereby achieving zero-voltage turn-on.

[0073] Mode 4: The AC input source provides a negative voltage, and the frequency of the pulse signal is limited.

[0074] See Figure 16As shown, the dead time control from the turn-off of the first switch 402 to the turn-on of the second switch 403 is the same as in mode 2. The dead time control from the turn-off of the second switch 403 to the turn-on of the first switch 402 differs due to the frequency limitation of the pulse signal. At time t2, the second switch 403 is turned off. Then at time t3, the second indicator signal changes from 0 to 1. However, at this time, the first pulse signal and / or the second pulse signal are greater than the frequency threshold, thus subject to frequency limitation. To reduce switching losses, the first switch 402 cannot be turned on at time t3, and similarly, it cannot be turned on at time t4. At time t5, the second indicator signal changes from 0 to 1 again, and simultaneously satisfies that the first pulse signal and / or the second pulse signal are not greater than the frequency threshold. At this time, the first switch 402 is turned on. When the first switch 402 is turned on, its drain-source voltage is 0, thereby achieving zero-voltage turn-on.

[0075] It should be noted that the control device 401 may further include a power module, which is used to draw power from the totem pole PFC circuit or an AC input source and supply power to the controller 404 and the dead-zone detection circuit 405 in the control device 401. This application embodiment will not list these details further.

[0076] Using a power supply device provided in this application embodiment, a dead-time detection circuit can detect the voltage of a first reference point in a totem-pole PFC circuit. A control device can generate a dead-time control signal based on the voltage of the first reference point and the voltage polarity of the AC input source voltage. The first reference point is the connection point between the source of the upper bridge arm switch and the drain of the lower bridge arm switch in the totem-pole PFC circuit. The control device in the power supply device can control the switching states of the upper bridge arm switch and the lower bridge arm switch in the totem-pole PFC circuit based on the dead-time control signal, so that the power supply device can perform optimal control of the totem-pole PFC circuit.

[0077] This application also provides a totem-pole PFC circuit control method. The control device is used to control the totem-pole PFC circuit, which includes a first switching transistor and a second switching transistor. The source of the first switching transistor and the drain of the second switching transistor are connected to a first reference point. The first input terminal of an AC input source is connected to the first reference point through an inductor. The control device includes a controller and a dead-time detection circuit. The dead-time detection circuit includes a detection capacitor and a detection resistor. The first end of the detection capacitor is connected to the first reference point, and the second end of the detection capacitor is connected to the first end of the detection resistor. The second end of the detection resistor is grounded. Applied to the controller, the method includes: generating a first dead-time control signal and a second dead-time control signal based on the voltage of the detection resistor and the polarity of the voltage input from the AC input source; controlling the switching state of the first switching transistor based on the first dead-time control signal; and controlling the switching state of the second switching transistor based on the second dead-time control signal. This method can achieve optimal control of the totem-pole PFC circuit. The implementation methods and corresponding technical effects of this application embodiment can refer to the technical effects obtained in the above embodiments, and repeated details are not described in detail.

[0078] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0079] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in one or more blocks of the flowchart illustrations and / or one or more blocks of the block diagrams.

[0080] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means that implement the functions specified in one or more flowcharts and / or one or more block diagrams.

[0081] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, such that the instructions, which execute on the computer or other programmable apparatus, provide steps for implementing the functions specified in one or more flowcharts and / or one or more block diagrams.

[0082] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the scope of protection of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A power supply device, characterized in that, The power supply device includes a totem pole PFC circuit and a control device. The totem pole PFC circuit includes a first switching transistor and a second switching transistor. The source of the first switching transistor and the drain of the second switching transistor are connected to a first reference point. The first input terminal of the AC input source is connected to the first reference point through an inductor. The control device includes a controller and a dead zone detection circuit. The dead zone detection circuit includes a detection capacitor and a detection resistor. The first end of the detection capacitor is connected to the first reference point, the second end of the detection capacitor is connected to the first end of the detection resistor, and the second end of the detection resistor is grounded. The controller is configured to generate a first dead-zone control signal and a second dead-zone control signal based on the voltage of the detection resistor and the polarity of the voltage input from the AC input source, and to control the switching state of the first switch transistor based on the first dead-zone control signal and the switching state of the second switch transistor based on the second dead-zone control signal.

2. The power supply device according to claim 1, characterized in that, The control device further includes: an AC input source polarity detection circuit; the AC input source polarity detection circuit is used to detect the positive or negative polarity of the voltage input by the AC input source.

3. The power supply device according to claim 2, characterized in that, The AC input source polarity detection circuit is specifically used for: Measure the first voltage at the first input terminal of the AC input source and the second voltage at the second input terminal of the AC input source, and calculate the voltage difference between the first voltage and the second voltage; When the voltage difference is greater than the first preset voltage, the voltage input by the AC input source is determined to be positive, and the first preset voltage is not less than 0. When the voltage difference is less than the second preset voltage, the voltage input by the AC input source is determined to be negative, and the second preset voltage is not greater than 0.

4. The power supply device according to any one of claims 1-3, characterized in that, The control device further includes: a voltage measurement module; the voltage measurement module is used to measure the voltage of the detection resistor.

5. The power supply device according to any one of claims 1-3, characterized in that, The controller is specifically configured to: generate an indication signal based on the voltage of the detection resistor and the polarity of the voltage input from the AC input source; and generate a first dead-zone control signal and a second dead-zone control signal based on the indication signal and the polarity of the voltage input from the AC input source. The indication signal is used to indicate the dead-zone state of the first switch and the second switch, and the indication signal includes a first indication signal and a second indication signal.

6. The power supply device according to claim 5, characterized in that, When it is determined that the voltage input from the AC input source is positive and the voltage of the detection resistor is less than the first threshold, the second indication signal is used to indicate that the first switch is in a dead zone state. When it is determined that the voltage input from the AC input source is positive and the voltage of the detection resistor is greater than the second threshold, the first indication signal is used to indicate that the second switch is in a dead zone state. When it is determined that the voltage input from the AC input source is negative and the voltage of the detection resistor is less than the third threshold, the first indication signal is used to indicate that the first switch is in a dead zone state. When it is determined that the voltage input to the AC input source is negative and the voltage of the detection resistor is greater than the fourth threshold, the second indication signal is used to indicate that the second switch is in a dead zone state; wherein, the first threshold is less than the second threshold, and the third threshold is less than the fourth threshold.

7. The power supply device according to claim 6, characterized in that, The controller specifically includes: a first multiplexer switch, a second multiplexer switch, a first comparator, a second comparator, and an inverter; the output terminal of the first multiplexer switch is connected to the negative terminal of the first comparator, and the output terminal of the second multiplexer switch is connected to the negative terminal of the second comparator; the output terminal of the second comparator is connected to the inverter; the first input terminal of the first multiplexer switch is used to input the voltage of the fourth threshold, and the second input terminal of the first multiplexer switch is used to input the voltage of the first threshold; the first input terminal of the second multiplexer switch is used to input the voltage of the third threshold, and the second input terminal of the second multiplexer switch is used to input the voltage of the second threshold; the positive terminal of the first comparator is used to receive the voltage of the detection resistor, and the positive terminal of the second comparator is used to receive the voltage of the detection resistor; When the voltage input to the AC input source is determined to be positive, the controller controls the first multiplexer switch to connect the first input terminal to the output terminal, and the controller controls the second multiplexer switch to connect the first input terminal to the output terminal; when the voltage input to the AC input source is determined to be negative, the controller controls the first multiplexer switch to connect the second input terminal to the output terminal, and the controller controls the second multiplexer switch to connect the second input terminal to the output terminal. The first comparator is used to output the first indication signal; The inverter is used to output the second indication signal.

8. The power supply device according to claim 6 or 7, characterized in that, The controller is specifically used for: When it is determined that the voltage input to the AC input source is positive, the first dead-zone control signal is generated according to the first indication signal, and the second dead-zone control signal is generated according to the second indication signal; When it is determined that the voltage input to the AC input source is negative, the first dead-time control signal is generated according to the second indication signal, and the second dead-time control signal is generated according to the first indication signal.

9. The power supply device according to claim 6 or 7, characterized in that, The control device further includes: a first pulse generation circuit, which generates a first pulse signal and a second pulse signal; the first pulse signal generates a first dead-zone control signal, and the second pulse signal generates a second dead-zone control signal. The controller is further configured to: when determining that the voltage input to the AC input source is positive, generate a first dead-zone control signal based on the first indication signal and the first pulse signal, and generate a second dead-zone control signal based on the second indication signal and the second pulse signal; when determining that the voltage input to the AC input source is negative, generate the first dead-zone control signal based on the second indication signal and the first pulse signal, and generate a second dead-zone control signal based on the first indication signal and the second pulse signal.

10. The power supply device according to claim 9, characterized in that, The control device further includes: a frequency detection module and a switching module; The frequency detection module is used to detect a first signal frequency and a second signal frequency, wherein the first signal frequency is the frequency of the first pulse signal and the second signal frequency is the frequency of the second pulse signal; The switching module is used to control the switching state of the first switching transistor according to the first signal frequency, and to control the switching state of the second switching transistor according to the second signal frequency.

11. The power supply device according to any one of claims 1-3, 6-7 or 10, characterized in that, The totem pole PFC circuit further includes a first diode and a second diode, wherein the positive terminal of the first diode and the negative terminal of the second diode are both connected to the second input terminal of the AC input source through a second reference point; the positive terminal of the second diode is grounded.

12. The power supply device according to any one of claims 1-3, 6-7 or 10, characterized in that, The totem pole PFC circuit further includes a third switch and a fourth switch. The source of the third switch and the drain of the fourth switch are both connected to the second input terminal of the AC input source through a second reference point. The drain of the third switch is connected to the drain of the first switch, and the source of the fourth switch is grounded. The control device further includes: a second pulse generation circuit, which is used to generate a third pulse signal and a fourth pulse signal; The controller is further configured to: control the switching state of the third switch transistor according to the third pulse signal, and control the switching state of the fourth switch transistor according to the fourth pulse signal.

13. The power supply device according to any one of claims 1-3, 6-7 or 10, characterized in that, The control device further includes a protection circuit, which includes a first Zener diode and a second Zener diode, and the protection circuit is connected in parallel with the detection resistor. The positive terminal of the first Zener diode is connected to the positive terminal of the second Zener diode, and the negative terminal of the second Zener diode is grounded.

14. A totem pole PFC circuit control method, wherein a control device is used to control the totem pole PFC circuit, the totem pole PFC circuit including a first switching transistor and a second switching transistor, the source of the first switching transistor and the drain of the second switching transistor are connected to a first reference point, and a first input terminal of an AC input source is connected to the first reference point through an inductor; the control device includes a controller and a dead-time detection circuit, the dead-time detection circuit including a detection capacitor and a detection resistor, a first terminal of the detection capacitor being connected to the first reference point, a second terminal of the detection capacitor being connected to a first terminal of the detection resistor, and a second terminal of the detection resistor being grounded; Applied to the controller, characterized in that, The method includes: Based on the voltage of the detection resistor and the polarity of the voltage input from the AC input source, a first dead zone control signal and a second dead zone control signal are generated. The switching state of the first switch is controlled according to the first dead-time control signal, and the switching state of the second switch is controlled according to the second dead-time control signal.

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