Circuit control method and electronic device

Abstract

The present disclosure relates to a circuit control method and an electronic device. A circuit comprises a self-excited soft start unit, a synchronous rectification module, an isolation unit and a fast charging circuit unit, wherein the self-excited soft start unit comprises a pulse width modulation (and / or pulse frequency modulation) control module and a self-excited soft start module; the isolation unit comprises a receiving module and a transmitting module; and the fast charging circuit unit comprises an insertion detection module and other high-frequency modules. The method comprises: when a secondary new fast charging circuit unit has detected an enabling instruction of a low-power mode, the secondary new fast charging circuit unit turning off power sources of all modules other than a power source of an insertion detection module, wherein for example, power sources of a synchronous rectification module, and a transmitting module of an isolation unit are both turned off; and a self-excited soft start unit turning off power sources of receiving modules, other than a detection receiving module, of the isolation unit, turning off power sources of other high-frequency modules, and switching to a low-frequency module for operation. The circuit does not need to maintain a precise secondary voltage output, thereby further reducing the standby power consumption.

Description

Circuit control methods and electronic devices Technical Field

[0001] This disclosure relates to the field of circuit technology, and more particularly to a circuit control method and electronic device. Background Technology

[0002] Currently, adapters are required to have a standby power consumption below a certain standard in order to be sold on the market. The losses caused by the entire path of the adapter include: 1. conduction loss, 2. switching loss, and 3. control circuit loss.

[0003] Since there are no significant load changes and frequent switching in standby mode, conduction losses can be disregarded. Currently, adapters achieving zero or low standby power consumption primarily focus on reducing switching losses and control circuit losses. Switching losses can be reduced by decreasing the PWM (Pulse Width Modulation) switching frequency. Reducing control circuit losses typically involves lengthening the entire loop control time. When the control circuit detects that the secondary circuit needs to operate, it sends a signal to an isolator (such as an optocoupler, magnetic coupler, capacitive coupler, or other digital isolation methods) to transmit the signal to the primary controller. The primary controller then generates a PWM signal and sends it to the driver transistor, controlling the transistor to produce the desired voltage for the secondary circuit.

[0004] However, existing traditional adapter structures still need to maintain a stable secondary output voltage during standby. The more precise the secondary output voltage or the narrower the output voltage range, the greater the power consumption required by the control loop circuit for the output voltage, resulting in relatively high standby power consumption. Summary of the Invention

[0005] In view of this, the purpose of this disclosure is to provide a circuit control method and an electronic device in which the circuit does not need to maintain a very precise secondary voltage output, thereby further reducing standby power consumption.

[0006] In a first aspect, embodiments of this disclosure provide a circuit control method. The circuit includes: a self-excited soft-start unit, a synchronous rectification module, an isolation unit, and a fast-charging circuit unit. The self-excited soft-start unit includes: a pulse width modulation (or / and pulse frequency modulation) control module and a self-excited soft-start module. The isolation unit includes: a receiving module and a transmitting module. The fast-charging circuit unit includes an insertion detection module and other high-frequency modules. The method includes: when the secondary fast-charging circuit unit detects a low-power mode start command, the fast-charging circuit unit turns off the power to both the synchronous rectification module and the transmitting module of the isolation unit; the self-excited soft-start unit turns off the power to all receiving modules of the isolation unit except for the receiving detection module; the self-excited soft-start unit turns off the power to all other high-frequency modules, while maintaining the power supply to the receiving detection module and the low-frequency circuit of the receiving module of the isolation unit.

[0007] In an optional embodiment of this application, the method further includes: when a low-power mode startup command is detected, the self-excited soft-start unit switches to a clock with a duty cycle of less than or equal to 5 / 95; wherein the duty cycle is related to the actual circuit and topology.

[0008] In an optional embodiment of this application, after the step of the self-excited soft-start unit turning off the power supply of all receiving modules of the isolation unit except for the receiving detection, the method further includes: the output voltage of the self-excited soft-start unit continuously rising or continuously falling.

[0009] In an optional embodiment of this application, the voltage of the auxiliary winding of the self-excited soft-start unit detection circuit is: if the voltage of the auxiliary winding is greater than a preset first threshold, the clock duty cycle of the self-excited soft-start unit is reduced or the clock frequency of the self-excited soft-start unit is lowered, so that the voltage of the auxiliary winding drops until the voltage is lower than a second threshold; if the voltage of the auxiliary winding is less than the preset second threshold, the clock duty cycle of the self-excited soft-start unit is increased or the clock frequency of the self-excited soft-start unit is increased, so that the voltage of the auxiliary winding rises until the voltage is higher than the first threshold.

[0010] In an optional embodiment of this application, the insertion detection module is powered by the voltage caused by the drain resonance of the MOS transistor.

[0011] In optional embodiments of this application, the above method further includes: when the insertion detection module detects a load insertion, turning on the power generator or low-dropout regulator module inside the fast charging circuit unit to make the fast charging circuit unit work; the fast charging circuit unit supplies power to the transmitting module of the isolation unit, and the detection circuit of the receiving module of the isolation unit receives the PWM signal sent by the fast charging circuit unit.

[0012] In optional embodiments of this application, the above method further includes: after the output voltage of the fast charging circuit unit stabilizes, determining the fast charging protocol of the inserted load; and adjusting the frequency or duty cycle supplied to the self-excited soft-start unit based on the fast charging protocol of the load.

[0013] In an optional embodiment of this application, the pulse width modulation (or / and pulse frequency modulation) control module includes: a first oscillation circuit, a second oscillation circuit, a switching switch, and a feedback signal failure detection signal; the second oscillation circuit includes: an RC oscillator with a duty cycle of 1 / 99; the ratio of the operating frequency of the second oscillation circuit to the operating frequency of the first oscillation circuit is greater than or equal to 1 / 6.

[0014] In an optional embodiment of this application, the above method further includes: determining whether the feedback signal failure detection signal input to the isolation unit has failed; if the feedback signal failure detection signal has failed, the switch switches the circuit to standby mode, and the second oscillation circuit outputs a PWM signal.

[0015] Secondly, embodiments of this disclosure also provide an electronic device for performing the circuit control method described above.

[0016] The embodiments disclosed herein bring the following beneficial effects:

[0017] This disclosure provides a circuit control method and an electronic device. The circuit includes: a self-excited soft-start unit, a synchronous rectification module, an isolation unit, and a fast-charging circuit unit. The self-excited soft-start unit includes: a pulse width modulation (or / and pulse frequency modulation) control module and a self-excited soft-start module. The isolation unit includes: a receiving module and a transmitting module. The fast-charging circuit unit includes an insertion detection module and other high-frequency modules. When the fast-charging circuit unit detects a low-power mode start command, it shuts off the power supply to the synchronous rectification module, the transmitting module of the isolation unit, and the insertion detection circuit of the fast-charging circuit unit, except for the power supply to the self-excited soft-start unit. The self-excited soft-start unit shuts off the power supply to the receiving module (except for the receiving detection circuit) and the high-frequency modules. The self-excited soft-start unit shuts off the power supply to the other high-frequency modules while maintaining the power supply to the receiving detection module. In this method, the circuit does not need to maintain a very precise secondary voltage output, thereby further reducing standby power consumption.

[0018] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Other features and aspects of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 is a schematic diagram of a conventional adapter low standby power consumption circuit structure provided in an embodiment of this disclosure;

[0021] Figure 2 is a schematic diagram of a low standby power consumption circuit structure of a conventional adapter secondary protocol unit provided in an embodiment of this disclosure;

[0022] Figure 3 is a schematic diagram of a zero standby power consumption circuit structure provided in an embodiment of this disclosure;

[0023] Figure 4 is a flowchart of a circuit control method provided in an embodiment of this disclosure;

[0024] Figure 5 is a schematic diagram of a conventional adapter AC-DC PWM controller circuit structure provided in an embodiment of this disclosure;

[0025] Figure 6 is a schematic diagram of the circuit structure of an adapter AC-DC PWM controller provided in an embodiment of this disclosure. Detailed Implementation

[0026] Various exemplary embodiments, features, and aspects of this disclosure will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0027] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0028] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0029] In this document, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Furthermore, the term "at least one" in this document means any combination of at least two of any one or more elements. For example, including at least one of A, B, and C can mean including any one or more elements selected from the set consisting of A, B, and C.

[0030] Furthermore, to better illustrate this disclosure, numerous specific details are set forth in the following detailed description. Those skilled in the art will understand that this disclosure can be practiced without certain specific details. In some instances, methods, means, components, and circuits well known to those skilled in the art have not been described in detail in order to highlight the main points of this disclosure.

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Currently, adapters are required to have a standby power consumption below a certain standard in order to be sold on the market. The losses caused by the entire path of the adapter include: 1. conduction loss, 2. switching loss, and 3. control circuit loss.

[0033] Since there are no significant load changes and frequent switching in standby mode, conduction losses can be disregarded. Currently, adapters achieving zero or low standby power consumption primarily focus on reducing switching losses and control circuit losses. Switching losses can be reduced by decreasing the PWM switching frequency. Reducing control circuit losses typically involves lengthening the entire loop control time. When the control circuit detects that the secondary circuit needs to operate, it sends a signal to an isolator (such as an optocoupler, magnetic coupler, capacitive coupler, or other digital isolation methods), which then transmits the signal to the primary controller. The primary controller generates a PWM signal and sends it to the driver transistor, controlling the transistor to produce the desired voltage for the secondary circuit.

[0034] Please refer to Figure 1 for a schematic diagram of a low standby power consumption circuit structure of an existing adapter and Figure 2 for a schematic diagram of a low standby power consumption circuit structure of a secondary protocol unit of an existing adapter.

[0035] As shown in Figure 1, the modules in the dashed line that require voltage to operate in the entire circuit include: the primary control circuit module and the isolation module. Specifically, if optocouplers or other digital isolation methods are used, the related circuits require power supply, as well as the secondary synchronous rectification circuit and the fast charging protocol detection circuit; if optocoupler isolation is used, the voltage regulator circuit needs to operate; if digital isolation is used, both the transmitting and receiving ends need power supply.

[0036] As shown in Figures 1 and 2, the difference between the circuits in Figure 2 and Figure 1 lies in whether the secondary protocol unit has power partitioning in low-power mode. In low-power power-off mode, only the insertion detection-related circuits are powered; other high-frequency modules of the protocol unit are powered off. Although the standby power consumption of Figure 2 is lower than that of Figure 1, Figure 2 still needs to maintain a stable secondary output voltage in standby mode. This part of the circuit still requires precise detection to ensure the output voltage is within the expected range.

[0037] Based on this, the present disclosure provides a circuit control method and electronic device, specifically a novel circuit structure and its control method with zero standby power consumption. The circuit does not need to maintain a very precise secondary voltage output, thereby further reducing standby power consumption.

[0038] To facilitate understanding of this embodiment, a circuit control method disclosed in this disclosure will first be described in detail.

[0039] Example 1:

[0040] This disclosure provides a circuit control method. The circuit includes: a self-excited soft-start unit, a synchronous rectification module, an isolation unit, and a fast charging circuit unit. The self-excited soft-start unit includes: a pulse width modulation (or / and pulse frequency modulation) control module and a self-excited soft-start module. The isolation unit includes: a receiving module and a transmitting module. The fast charging circuit unit includes an insertion detection module and other high-frequency modules.

[0041] Referring to Figure 3, a schematic diagram of a zero standby power consumption circuit structure can be seen. Figure 3 shows the novel zero standby power consumption circuit structure provided in this embodiment, with the modules requiring power supply indicated by the dashed lines. The difference between the modules requiring power supply in standby mode in this embodiment and those in traditional circuit structures is that in this embodiment, only the insertion detection module needs to work in the secondary wake-up circuit; other high-frequency modules do not require power supply, even the synchronous rectification module and the isolation unit circuit.

[0042] As shown in Figure 3, the biggest difference between the standby mode and the traditional circuit structure in this embodiment is: 1. Insertion detection power supply; 2. The receiving and detection circuit of the primary AC-DC PWM controller (i.e., the pulse width modulation control module of this embodiment) or the self-excited soft-start module automatically switches to the default minimum PWM duty cycle output or PFM (Pulse Frequency Modulation) mode when no feedback signal is received from the secondary; 3. The primary AC-DC PWM controller or the self-excited soft-start circuit detects the voltage of the auxiliary coil to adjust the voltage output to the secondary to ensure that the secondary output voltage does not exceed the expected value.

[0043] Based on the above description, referring to the flowchart of a circuit control method shown in Figure 4, the circuit control method includes the following steps:

[0044] In step S402, when the secondary fast charging circuit unit detects the low-power mode start command, the fast charging circuit unit will shut down the power supply of the transmitter module of the synchronous rectification module and the isolation unit.

[0045] When a low-power mode start command is detected, the fast charging circuit unit shuts off the power to all modules in the secondary circuit except for the power supply to the fast charging circuit unit's insertion detection circuit, such as the synchronous rectification module and the transmitter module of the isolation unit.

[0046] As shown in Figure 3, in this embodiment, the AC-DC PWM control unit (i.e., the pulse width modulation control module mentioned above) and the self-excited soft-start module can be combined into a self-excited soft-start unit. When the system detects that it needs to be in a low-power mode (i.e., the low-power mode start command), it will turn off the power supply of the M2 MOS synchronous rectification module.

[0047] Furthermore, the fast charging circuit unit can also shut off the power to the transmitting module.

[0048] In step S404, the self-excited soft-start unit shuts off the power to all receiving modules of the isolation unit except for the receiving detection module.

[0049] As shown in Figure 3, the self-excited soft-start unit of this embodiment can also turn off the power supply of the receiving module of the isolation unit, except for the receiving and detection circuits and the high-frequency circuit module.

[0050] In step S406, the self-excited soft-start unit shuts off the power supply to all other high-frequency modules while maintaining the power supply to the insertion detection module.

[0051] As shown in Figure 3, the entire system in this embodiment can also turn off the power supply of all high-frequency modules of the new fast charging circuit unit except for the insertion detection module, and only maintain the power supply of the insertion detection module of the new fast charging circuit unit.

[0052] This disclosure provides a circuit control method. The circuit includes: a self-excited soft-start unit, a synchronous rectification module, an isolation unit, and a fast-charging circuit unit. The self-excited soft-start unit includes a pulse width modulation (or / and pulse frequency modulation) control module and a self-excited soft-start module. The isolation unit includes a receiving module and a transmitting module. The fast-charging circuit unit includes an insertion detection module and other high-frequency modules. When a low-power mode start command is detected, the fast-charging circuit unit shuts off the power supply to all circuits except the insertion detection module, such as the synchronous rectification module and the transmitting module of the isolation unit. The self-excited soft-start unit shuts off the power supply to all circuits except the receiving detection module and the high-frequency circuit modules. The self-excited soft-start unit shuts off the power supply to other high-frequency modules while maintaining the power supply to the receiving detection module. In this method, the circuit does not need to maintain a very precise secondary voltage output, thereby further reducing standby power consumption.

[0053] In some embodiments, when a low-power mode start command is detected, the self-oscillating soft-start unit switches to a clock with a duty cycle of less than or equal to 5 / 95; wherein the duty cycle is related to the actual circuit and topology.

[0054] When the system detects the need for a low-power mode, the self-oscillating soft-start unit can switch to its own low-frequency, non-traditional 50 / 50 (e.g., 5 / 95) duty cycle clock. The duty cycle depends on the actual circuit and topology, and may be smaller than 5 / 95 in low-power mode.

[0055] In some embodiments, after the self-excited soft-start unit turns off the power to both the receiving module and the high-frequency module, the method further includes: the output voltage of the self-excited soft-start unit continuously rising or continuously falling.

[0056] As shown in Figure 3, since the power supply to the isolation unit and the synchronous rectification module of M2 MOS are both off, the primary self-excited soft-start unit has no feedback signal to adjust the output voltage, which will cause the output voltage to keep rising or falling.

[0057] In some embodiments, the voltage of the auxiliary winding of the self-excited soft-start unit detection circuit is: if the voltage of the auxiliary winding is greater than a preset first threshold, the clock duty cycle of the self-excited soft-start unit is reduced or the clock frequency of the self-excited soft-start unit is lowered, so that the voltage of the auxiliary winding drops until the voltage is lower than a second threshold; if the voltage of the auxiliary winding is less than the preset second threshold, the clock duty cycle of the self-excited soft-start unit is increased or the clock frequency of the self-excited soft-start unit is increased, so that the voltage of the auxiliary winding rises until the voltage is higher than the first threshold.

[0058] The self-excited soft-start unit detects the voltage of the auxiliary winding. When the voltage of the auxiliary winding is greater than the preset first threshold Vmax, it will reduce the clock duty cycle or decrease the clock frequency of the self-excited soft-start. Conversely, when the voltage of the auxiliary winding is less than the preset second threshold (e.g., 3.3V), it will increase the clock duty cycle or increase the clock frequency of the self-excited soft-start.

[0059] In some embodiments, the insertion detection module is powered by the voltage caused by the drain resonance of the MOSFET.

[0060] As shown in Figure 3, the insertion detection module of the novel fast charging circuit unit is powered by the voltage generated by the resonance of the drain terminal of the M2 MOS. Because only the insertion detection module has power in the entire secondary circuit, the power consumption loss is very small.

[0061] In some embodiments, when the insertion detection module detects a load insertion, it turns on the power generator or low-dropout regulator module inside the fast charging circuit unit to make the fast charging circuit unit work; the fast charging circuit unit supplies power to the isolation unit transmitter module and the synchronous rectification module, and the isolation unit receives the PWM signal sent by the fast charging circuit unit and then switches from the low-frequency low-power mode to the normal operation mode.

[0062] When the insertion detection module detects a load insertion, it will turn on the power generator or low-dropout regulator (LDO) module inside the new fast charging circuit unit to enable the new fast charging circuit unit to work, so that the isolation unit can receive the default PWM signal sent by the new fast charging circuit unit.

[0063] In some embodiments, after the output voltage of the fast charging circuit unit stabilizes, the fast charging protocol of the inserted load is determined; the frequency or duty cycle supplied to the self-excited soft-start unit is adjusted based on the fast charging protocol of the load.

[0064] Once the output voltage of the new fast charging circuit unit stabilizes, it can be determined which fast charging protocol the inserted load needs to use. After determining the required output voltage, adjusting the frequency or duty cycle supplied to the self-oscillating soft-start unit can achieve the purpose of adjusting the output voltage.

[0065] The dashed boxes in Figures 1, 2, and 3 represent the modules that need to operate or be powered in standby mode. Existing conventional adapter structures (as shown in Figures 1 and 2) also require maintaining a stable secondary output voltage in standby mode. The more precise the secondary output voltage or the narrower the output voltage range, the greater the power consumption required by the control loop circuit for the output voltage. The circuit of this embodiment shown in Figure 3 does not require maintaining a very precise secondary voltage output. In standby mode, the added oscillation circuit 2 consumes less power than the original oscillation circuit 1.

[0066] Example 2:

[0067] This embodiment provides another circuit control method, which is implemented based on the above embodiment. This embodiment focuses on describing the implementation of the pulse width (or / and pulse frequency modulation) modulation control module.

[0068] Figure 5 shows a schematic diagram of a conventional adapter AC-DC PWM controller circuit. The frequency compensation circuit in Figure 5 adjusts the output frequency of the oscillation circuit based on the input signal from the isolation unit, thus generating the output PWM frequency. The dashed boxes indicate modules requiring power in standby mode, such as the oscillation circuit, frequency compensation, slope compensation, and the three comparators. Even though the operating frequency can be reduced in standby to lower the average current during operation, these modules still require continuous power, resulting in persistent static current loss.

[0069] In some embodiments, the pulse width modulation (or / and pulse frequency modulation) control module includes: a first oscillation circuit (i.e., oscillation circuit 1), a second oscillation circuit (i.e., oscillation circuit 2), a switching switch, and a feedback signal failure detection signal; the second oscillation circuit includes: a low-frequency oscillator, such as a 10kHz RC oscillator, the duty cycle of the RC oscillator being 1 / 99, the frequency and default duty cycle of this oscillator being related to the system topology and load; the ratio of the operating frequency of the second oscillation circuit to the operating frequency of the first oscillation circuit is greater than or equal to (e.g., 1 / 6 or a higher ratio, such as 1 / 20).

[0070] Refer to Figure 6 for a schematic diagram of an adapter AC-DC PWM controller circuit structure. The AC-DC PWM controller shown in Figure 6 is the pulse width modulation (or / and pulse frequency modulation) control module of this embodiment. As shown in Figures 5 and 6, the differences between the traditional AC-DC PWM controller and the AC-DC PWM controller of this embodiment are: oscillation circuit, feedback signal failure detection, and switching switch. The oscillation circuit 1 of this embodiment is the same as the oscillation circuit used in the AC-DC PWM of a traditional adapter; the oscillation circuit 2 is an RC oscillator with a low-frequency clock, such as 10KHz, and the duty cycle of this oscillator output is not 50 / 50, but 1 / 99; the oscillation circuit 2 defaults to high time occupying 1% of a cycle and low time occupying 99% of a cycle. The operating frequency of this oscillation circuit 2 is at least 1 / 6 of the traditional operating frequency of the oscillation circuit 1. Taking 1 / 6 of the standby operating frequency as an example, the dynamic power consumption of the oscillation circuit 2 in standby mode is 1 / 6 of that of the oscillation circuit 1. Therefore, within the allowable range, the standby operating frequency can be increased by a higher ratio, such as 1 / 20, to reduce the power consumption during standby.

[0071] As shown in Figures 5 and 6, both figures use dashed boxes to represent modules that require power during standby. Figure 5 shows more modules requiring power during standby than Figure 6. The circuit structure in Figure 6 includes an additional oscillator circuit 2 compared to Figure 5. Oscillator circuit 2 only operates during standby, while oscillator circuit 1 is powered off. This is because it reduces dynamic power consumption caused by the switch, and the frequency of oscillator circuit 2 is at least 1 / 6 of the frequency of oscillator circuit 1, thus reducing the dynamic power consumption of the switch by at least 1 / 6. Figure 6 has fewer operating modules than Figure 5 during standby, resulting in lower standby power consumption and leakage current. A duty cycle of 1 / 99 means that the high and low frequencies occupy 1% and 99% of the entire cycle, respectively.

[0072] In some embodiments, it is determined whether the feedback signal failure detection signal input to the isolation unit has failed; if the feedback signal failure detection signal fails, the switch switches the circuit to standby mode, and the second oscillation circuit outputs a PWM signal.

[0073] The feedback signal failure detection in this embodiment detects whether the signal input from the isolation unit is faulty. If it is faulty, the selection switch is switched to standby mode, at which time the oscillation circuit 2 provides the output PWM signal.

[0074] The feedback signal failure detection standard differs depending on the type of isolation unit. When the isolation unit is a digital isolation type, such as magnetic coupling, capacitive coupling, millimeter wave, or similar isolation method, if no signal is received from the secondary side for more than one cycle of oscillation circuit 2, the secondary side is considered to have failed. The feedback signal failure detection signal is then set high, and the primary side enters standby mode. When the isolation unit is an optocoupler, the process depends on how the system handles the secondary power supply. If the power supply to the secondary optocoupler is turned off, the handling method is similar to that of digital isolation. If no optocoupler feedback signal is received within one cycle of oscillation circuit 2, it is considered to have failed. If the optocoupler is continuously powered, the feedback signal failure will not be triggered in this embodiment. However, this embodiment still turns off the power supply to the fast charging circuit unit except for the insertion detection circuit, as well as the synchronous rectification circuit.

[0075] In the standby mode, the AC-DC PWM module in the adapter self-excited soft-start unit of this embodiment does not rely on the secondary feedback signal to adjust the duty cycle of the primary AC-DC PWM. Because the secondary circuit does not control the primary PWM controller for a long time, its output will cause the secondary voltage to fluctuate. The voltage fluctuation range is 3.3V to Vmax, where the maximum voltage supported by Vmax is determined by the maximum power supported by the load. For example, if the maximum supported power is 28V 5A, then the Vmax voltage is 28V.

[0076] For example, if the maximum power is 48V 5A, then Vmax is 48V. The AC-DC PWM controller of this embodiment detects the voltage of the auxiliary coil. When the voltage exceeds the expected voltage Vmax, the oscillation circuit 2 of this embodiment stops outputting the PWM signal, causing the secondary voltage to drop from Vmax. When it drops to about 3.3V, the oscillation circuit 2 of this embodiment starts oscillating, and the secondary voltage slowly rises from 3.3V.

[0077] When the secondary insertion detection circuit of this embodiment detects the insertion of a device, it will turn on the power to the secondary circuit, such as the novel fast charging circuit unit or the isolation circuit unit, so that the secondary circuit can start working. After the secondary circuit is working normally, it will start sending a signal to the primary module through the isolation unit. When the primary AC-DC PWM circuit detects the feedback signal failure and the detection signal goes low, it will switch the system back to normal working mode.

[0078] In summary, the circuits provided in this disclosure can be applied to applications such as adapters, power strips, energy storage, AC-DC primary step-down, and AC-DC secondary step-down. In standby mode, the secondary winding of this disclosure only requires power to the insertion detection circuit. In standby mode, the insertion detection circuit is powered by the reverse bias of the synchronous rectifier MOSFET, and its power consumption in standby mode is less than 1uA or even 100nA. In standby mode, the isolation circuit does not require power or operation. In standby mode, only the insertion detection circuit requires power; other high-frequency modules do not require power.

[0079] In this embodiment of the invention, when the self-excited soft-start circuit unit does not receive a feedback signal from the secondary side during standby, the duty cycle of the PWM output is in the minimum mode, and the clock is switched to be generated by the internal oscillation circuit 2. In this embodiment of the invention, the primary side supports PWM and PFM control modes when there is zero standby power consumption. In this embodiment of the invention, the self-excited soft-start circuit detects the voltage of the auxiliary coil and adjusts the PWM output duty cycle to ensure that the secondary output voltage is within the expected range. In this embodiment of the invention, the transformer secondary voltage output range is 3V to Vmax, where Vmax is determined by the highest voltage at the maximum supported power.

[0080] The zero standby power consumption of the embodiments of this disclosure is applicable to isolation circuits using methods such as optocouplers, magnetic couplers, capacitive couplers, and other digital isolation. The zero standby power consumption related circuit design of the embodiments of this disclosure is easier to implement than that of traditional adapter zero standby power consumption related circuits under the same standby power consumption conditions, and the specifications are lower than those of traditional standby power consumption circuits.

[0081] This embodiment of the disclosure uses open-loop control in zero standby power consumption mode and switches back to closed-loop control mode in normal operation mode. In zero standby power consumption mode, this embodiment of the disclosure can turn off PFC (Power Factor Correction) and LLC (Inductor-Inductor-Capacitor) circuits if the system has them, that is, the primary side switches PFC and LLC to bypass mode.

[0082] The self-excited soft start of this embodiment is a part of the functions of a traditional AC-DC PWM controller, such as high-voltage power supply and PWM and PFM mode switching; the driving transistors supported by this embodiment include traditional silicon MOSFETs, gallium nitride (GaN) transistors and silicon carbide (SiC) transistors.

[0083] Because the output voltage of this embodiment in standby mode is over a wide range and does not require maintaining a specific voltage during standby, the circuit design, implementation, and power consumption are simpler than those in normal operating mode. Furthermore, because fewer modules operate in standby mode compared to conventional adapters, the power consumption of this embodiment is superior to conventional adapter solutions.

[0084] Example 3:

[0085] Corresponding to the above method embodiments, this disclosure provides an electronic device for executing the circuit control method provided in the foregoing embodiments.

[0086] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system and / or device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0087] Furthermore, in the description of the embodiments of this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this disclosure based on the specific circumstances.

[0088] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of this disclosure, or the parts that contribute to the prior art, or parts of the technical solutions, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods in the various embodiments of this disclosure. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0089] In the description of the embodiments of this disclosure, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this disclosure. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0090] Finally, it should be noted that the above embodiments are merely specific implementations of the embodiments of this disclosure, used to illustrate the technical solutions of the embodiments of this disclosure, and not to limit them. The protection scope of the embodiments of this disclosure is not limited thereto. Although the embodiments of this disclosure have been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the embodiments of this disclosure, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure, and should all be covered within the protection scope of the embodiments of this disclosure. Therefore, the protection scope of the embodiments of this disclosure should be determined by the protection scope of the claims.

Claims

1. A circuit control method, characterized in that, The circuit includes: a self-excited soft-start unit, a synchronous rectification module, an isolation unit, and a fast-charging circuit unit; the self-excited soft-start unit includes: a pulse width modulation (or / and pulse frequency modulation) control module and a self-excited soft-start module; the isolation unit includes: a receiving module and a transmitting module; the fast-charging circuit unit includes an insertion detection module and other high-frequency modules; the method includes: When the secondary fast charging circuit unit detects the low-power mode start command, the fast charging circuit unit shuts off the power to the synchronous rectification module and the transmission module of the isolation unit. The self-excited soft-start unit shuts off the power to all receiving modules of the isolation unit except for the receiving detection module. The self-excited soft-start unit shuts off the power supply to the other high-frequency modules while maintaining the power supply to the insertion detection module.

2. The method according to claim 1, characterized in that, The method further includes: When a low-power mode startup command is detected, the self-oscillating soft-start unit switches to a clock with a duty cycle of less than or equal to 5 / 95; wherein the duty cycle is related to the actual circuit and topology.

3. The method according to claim 1, characterized in that, After the step of the self-excited soft-start unit turning off the power to all receiving modules of the isolation unit except for the receiving detection module, the method further includes: The output voltage of the self-excited soft-start unit keeps rising or falling.

4. The method according to claim 1, characterized in that, The method further includes: The self-excited soft-start unit detects the voltage of the auxiliary winding of the circuit; If the voltage of the auxiliary winding is greater than a preset first threshold, the clock duty cycle of the self-excited soft-start unit is reduced or the clock frequency of the self-excited soft-start unit is reduced, so that the voltage of the auxiliary winding drops until the voltage is lower than a second threshold. If the voltage of the auxiliary winding is less than a preset second threshold, the clock duty cycle of the self-excited soft-start unit is increased or the clock frequency of the self-excited soft-start unit is increased, so that the voltage of the auxiliary winding rises until the voltage is higher than the first threshold.

5. The method according to claim 1, characterized in that, The insertion detection module is powered by the voltage caused by the drain resonance of the MOS transistor.

6. The method according to claim 1, characterized in that, The method further includes: When the insertion detection module detects a load insertion, it turns on the power generator or low-dropout regulator module inside the fast charging circuit unit to make the fast charging circuit unit work. The fast charging circuit unit supplies power to the transmitting module of the isolation unit, and the detection circuit of the receiving module of the isolation unit receives the PWM signal sent by the fast charging circuit unit.

7. The method according to claim 6, characterized in that, The method further includes: Once the output voltage of the fast charging circuit unit stabilizes, the fast charging protocol of the inserted load is determined. The frequency or duty cycle supplied to the self-excited soft-start unit is adjusted based on the fast charging protocol of the load.

8. The method according to any one of claims 1-7, characterized in that, The pulse width modulation (or / and pulse frequency modulation) control module includes: a first oscillation circuit, a second oscillation circuit, a switching switch, and a feedback signal failure detection signal; The second oscillation circuit includes an RC oscillator with a duty cycle of 1 / 99; the ratio of the operating frequency of the second oscillation circuit to the operating frequency of the first oscillation circuit is greater than or equal to 1 / 6.

9. The method according to claim 8, characterized in that, The method further includes: Determine whether the feedback signal failure detection signal input to the isolation unit has failed; If the feedback signal failure detection signal fails, the switch will switch the circuit to standby mode, and the second oscillation circuit will output a PWM signal.

10. An electronic device, characterized in that, The electronic device is used to perform the circuit control method according to any one of claims 1-9.

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