Voltage conversion circuit, power conversion method and electronic device

Abstract

An embodiment of the present application provides a voltage conversion circuit, a power conversion method, and an electronic device. The voltage conversion circuit includes a control module, a first field-effect transistor, a second field-effect transistor, a switch, and a switch control module; a first pole of the first field-effect transistor is connected to a power input port, a second pole of the first field-effect transistor is connected to a power output port, and a gate of the first field-effect transistor is connected to the control module; one end of the switch is connected to the second pole of the first field-effect transistor, the other end of the switch is connected to the second field-effect transistor, a gate of the second field-effect transistor is connected to the control module, and a second pole of the second field-effect transistor is grounded; one end of the switch control module is connected between the second pole of the first field-effect transistor and the power output port for collecting a first current, and the other end of the switch control module is connected to the switch and the control module; when the first current is less than a first threshold, the switch control block controls the switch to turn off, and the control module adjusts the first field-effect transistor to adjust the output voltage.

Description

Technical Field

[0001] This application belongs to the field of communication technologies, and particularly relates to a voltage conversion circuit, a voltage conversion method, and an electronic device. Background Art

[0002] With the rapid development of communication technologies, the demand for diversified functions of electronic devices such as mobile phones and tablet computers is also getting higher and higher. There are also more and more peripheral modules integrated on electronic devices. Therefore, the voltage configurations that need to be supported on electronic devices are correspondingly increasing. In practical applications, a voltage conversion circuit is usually provided in an electronic device. The voltage conversion circuit can convert an input voltage into an output voltage and cooperate with a feedback loop to achieve voltage regulation.

[0003] In the existing technologies, different load modes of the voltage conversion circuit usually correspond to different working modes. Specifically, in the case where the load mode is a heavy load mode, the voltage conversion circuit generally uses the Pulsewidth Modulation (PWM) mode. In this mode, the period width of the pulse is fixed. In the case where the load mode is a light load mode, the voltage conversion circuit generally uses the Pulse Frequency Modulation (PFM) mode. In this mode, the period width of the pulse is not fixed.

[0004] However, in the case where the load mode is a light load mode, although the voltage conversion circuit using the PFM mode is beneficial to obtaining higher efficiency, when the PFM mode is used for voltage conversion, since the period width of the pulse is not fixed, it is very easy to generate large ripples and more frequency components. In this way, it is very easy to generate electromagnetic interference on multiple frequencies of the electronic device, seriously affecting the use experience of the electronic device. Summary of the Invention

[0005] This application aims to provide a voltage conversion circuit, a voltage conversion method, and an electronic device to solve the problem of relatively large electromagnetic interference generated by the existing voltage conversion circuit.

[0006] To solve the above technical problems, this application is implemented as follows:

[0007] In a first aspect, this application discloses a voltage conversion circuit, where the voltage conversion circuit includes: a control module, a first field-effect transistor, a second field-effect transistor, a switch, and a switch control module;

[0008] A first pole of the first field-effect transistor is connected to a power input port, a second pole of the first field-effect transistor is connected to a power output port, and a gate of the first field-effect transistor is connected to the control module;

[0009] One end of the switch is connected to the second pole of the first field-effect transistor, the other end of the switch is connected to the first pole of the second field-effect transistor, the gate of the second field-effect transistor is connected to the control module, and the second pole of the second field-effect transistor is grounded;

[0010] One end of the switch control module is connected between the second pole of the first field-effect transistor and the power output port for collecting a first current, and the other end of the switch control module is respectively connected to the switch and the control module;

[0011] When the first current is less than a first threshold, the switch control block controls the switch to disconnect, and the control module adjusts the first field-effect transistor to adjust the output voltage.

[0012] In a second aspect, the present application also discloses a voltage conversion method, which is applied to the voltage conversion circuit described in any one of the above; the voltage conversion method includes:

[0013] Collect the first current between the first field-effect transistor and the power output port;

[0014] When the first current is less than a first threshold, the switch control block controls the switch to disconnect;

[0015] The control module adjusts the first field-effect transistor to adjust the output voltage.

[0016] In a third aspect, the present application also discloses an electronic device, which includes: the voltage conversion circuit described in any one of the above.

[0017] In the embodiments of the present application, by adding a switch between the first field-effect transistor and the second field-effect transistor and connecting the switch control module between the first field-effect transistor and the power output port to collect the first current, the first current can be used to evaluate the load condition of the voltage conversion circuit. When the first current is less than a first threshold, it can be considered that the voltage conversion circuit is in a light load mode. At this time, the switch control module can control the switch to disconnect to disconnect the connection between the first field-effect transistor and the second field-effect transistor. The control module can achieve the purpose of adjusting the output voltage by adjusting the first field-effect transistor without sending a switch signal to the first field-effect transistor and the second field-effect transistor. In this way, the electromagnetic interference generated by the voltage conversion circuit in the light load mode can be greatly reduced, and the user experience of the electronic device can be improved.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of embodiments in conjunction with the accompanying drawings, in which:

[0020] Figure 1 is a schematic structural diagram of a voltage conversion circuit according to an embodiment of the present application;

[0021] Figure 2 is a schematic structural diagram of another voltage conversion circuit according to an embodiment of the present application;

[0022] Figure 3 is a schematic structural diagram of yet another voltage conversion circuit according to an embodiment of the present application;

[0023] [[ID=!6]] Figure 4 is a flowchart of steps of a voltage conversion method according to an embodiment of the present application;

[0024] Reference numerals: 10 - control module, 11 - first field effect transistor, 12 - second field effect transistor, 13 - switch, 14 - switch control module, 141 - sampling device, 142 - digital-to-analog conversion device, 143 - reference voltage source, 144 - voltage comparator, 15 - power inductor, 151 - first power inductor, 152 - second power inductor, 16 - capacitor, 17 - feedback module, 100 - power input port, 200 - power output port. Detailed Embodiments

[0025] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary only for explaining the present invention and should not be construed as limiting the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts fall within the scope of protection of the present application.

[0026] The terms "first" and "second" in the description and claims of the present application may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "plural" is two or more. In addition, "and / or" in the description and claims means at least one of the connected objects. The character " / " generally indicates an "or" relationship between the associated objects before and after.

[0027] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0028] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0029] Referring to Figure 1 , a schematic structural diagram of a voltage conversion circuit according to an embodiment of the present application is shown. As Figure 1 shown, the voltage conversion circuit may specifically include: a control module 10, a first field effect transistor 11, a second field effect transistor 12, a switch 13, and a switch control module 14;

[0030] The first pole of the first field effect transistor 11 is connected to the power input port 100, the second pole of the first field effect transistor 11 is connected to the power output port 200, and the gate of the first field effect transistor 11 is connected to the control module 10;

[0031] One end of the switch 13 is connected to the second pole of the first field effect transistor 11, the other end of the switch 13 is connected to the first pole of the second field effect transistor 12, the gate of the second field effect transistor 12 is connected to the control module 10, and the second pole of the second field effect transistor 12 is grounded;

[0032] One end of the switch control module 14 is connected between the second pole of the first field effect transistor 11 and the power output port 200 for collecting a first current, and the other end of the switch control module 14 is respectively connected to the switch 13 and the control module 10;

[0033] When the first current is less than a first threshold, the switch control module can control the switch 13 to disconnect, and the control module 10 adjusts the first field effect transistor 11 to adjust the output voltage.

[0034] In the embodiments of the present application, a switch 13 is added between the first field-effect transistor 11 and the second field-effect transistor 12, and the switch control module 14 is connected between the first field-effect transistor 11 and the power output port 200 to collect a first current, and the first current can be used to evaluate the load condition of the voltage conversion circuit. When the first current is less than the first threshold, it can be considered that the voltage conversion circuit is in a light load mode. At this time, the switch control module 14 can control the switch 13 to be turned off to disconnect the connection between the first field-effect transistor 11 and the second field-effect transistor 12. The control module 10 can achieve the purpose of adjusting the output voltage by adjusting the first field-effect transistor 11 without sending a switching signal to the first field-effect transistor 11 and the second field-effect transistor 12. In this way, the electromagnetic interference generated by the voltage conversion circuit in the light load mode can be greatly reduced, and the usage experience of the electronic device can be improved.

[0035] Specifically, the power input port 100 can be connected to the power supply in the electronic device for accessing an input voltage. The power conversion circuit can be used to convert the input voltage into an output voltage and output it from the power output port 200. The power output port 200 can be connected to the load module, and the output voltage can be used to supply power to the load module.

[0036] Exemplarily, the load module can include, but is not limited to, functional modules that require power, such as a camera module, a sensing module, etc.

[0037] In practical applications, the greater the amount of power required by the load module, the greater the output voltage that the power output port 200 needs to output, and the greater the value of the first current. The first current is positively correlated with the power demand of the load module. Therefore, the first current can be used to evaluate the load condition of the voltage conversion circuit.

[0038] Specifically, when the first current is greater than or equal to the first threshold, it can be considered that the load device requires a large amount of power, and the load mode of the voltage conversion circuit is a heavy load mode. When the first current is less than the first threshold, it can be considered that the load device requires a small amount of power, and the load mode of the voltage conversion circuit is a light load mode.

[0039] It should be noted that in practical applications, the specific value of the first threshold can be set according to actual conditions, and the embodiments of the present application may not limit the specific value of the first threshold.

[0040] In the embodiment of the present application, the first pole of the first field effect transistor 11 can be connected to the power input port 100, the second pole of the first field effect transistor 11 can be connected to the power output port 200, and the gate of the first field effect transistor 11 can be connected to the control module 10. In practical applications, the control module 10 can control the conduction or disconnection of the first pole and the second pole of the first field effect transistor 11 by inputting a switching signal to the gate.

[0041] Specifically, the first pole of the first field effect transistor 11 can be one of the source and the drain, and the second pole of the first field effect transistor 11 can be the other of the source and the drain. The embodiment of the present application does not make any limitation in this regard.

[0042] In the embodiment of the present application, one end of the switch 13 can be connected to the second pole of the first field effect transistor 11, and the other end of the switch 13 can be connected to the second end of the second field effect transistor 12. The second pole of the second field effect transistor 12 can be grounded, and the gate of the second field effect transistor 12 can be connected to the control module 10. In practical applications, the control module 10 can control the conduction or disconnection of the first pole and the second pole of the second field effect transistor 12 by inputting a switching signal to the gate.

[0043] Specifically, the first pole of the second field effect transistor 12 can be one of the source and the drain, and the second pole of the second field effect transistor 12 can be the other of the source and the drain. The embodiment of the present application does not make any limitation in this regard.

[0044] In the embodiment of the present application, since one end of the switch control module 14 is connected between the second pole of the first field effect transistor 11 and the power output port 200, when the first current collected by the switch control module 14 is less than the first threshold, it can be considered that the load mode of the voltage conversion circuit is a light load mode. At this time, the switch control module 14 can output a switch control signal to the switch 13, and the switch control signal can control the switch 13 to disconnect, so as to disconnect the connection between the first field effect transistor 11 and the second field effect transistor 12. At the same time, the switch control module 14 can also transmit the switch control signal to the control module 10. In response to the switch control signal, the control module 10 can control the first pole and the second pole of the first field effect transistor 11 to conduct and maintain the conducting state.

[0045] As Figure 1 shown, when the switch 13 is disconnected and the first pole and the second pole of the first field effect transistor 11 are conducting, the input voltage input from the power input port 100 can be converted into an output voltage and output from the power output port 200 only through the first field effect transistor 11. The relationship between the input voltage and the output voltage can be expressed by the following formula:

[0046] V OUT =VIN -V MOS (Formula 1)

[0047] Wherein, V IN represents the input voltage connected to the power input port 100, and V OUT represents the output voltage output from the power output port 200, and V MOS represents the on-voltage drop of the first field-effect transistor 11.

[0048] In practical applications, when the field-effect transistor is turned on, it can be equivalent to an electrical device with an adjustable resistance. By adjusting the equivalent resistance of the field-effect transistor, the on-voltage drop of the field-effect transistor can be adjusted.

[0049] It can be seen from Formula 1 that when the input voltage V IN is known, by adjusting the on-voltage drop V MOS of the first field-effect transistor 11, the output voltage V OUT can be adjusted. Moreover, since the first field-effect transistor 11 remains in the on state, the control module 10 does not need to send switching signals to the first field-effect transistor 11 and the second field-effect transistor 12, and the first field-effect transistor 11 and the second field-effect transistor 12 do not have a switching function. Therefore, the electromagnetic interference generated by the voltage conversion circuit in the light load mode can be greatly reduced, and the user experience of the electronic device can be improved.

[0050] Optionally, the voltage conversion circuit may further include: a power inductor 15, and the power inductor 15 is connected between the second pole of the first field-effect transistor 11 and the power output port 200. The power inductor 15 can achieve charging energy storage and discharging energy dissipation through repeated charging and discharging processes, and can also pass a direct current.

[0051] Optionally, the voltage conversion circuit may further include: a feedback module 17, one end of the feedback module 17 is connected between the second pole of the first field-effect transistor 11 and the power output port 200, and the other end of the feedback module 17 is connected to the control module 10.

[0052] In practical applications, since one end of the feedback module 17 is connected between the second pole of the first field-effect transistor 11 and the power output port 200, the feedback module 17 can be used to collect the real-time output voltage output from the power output port 200 and feed the real-time output voltage back to the control module 10, so that the control module 10 can further adjust the output voltage with reference to the real-time output voltage until the real-time output voltage is as close as possible to the theoretical output voltage.

[0053] In some alternative embodiments of the present application, the voltage conversion circuit may include a first output mode and a second output mode; wherein, when the first current is less than the first threshold, the voltage conversion circuit switches to the first output mode, switch 13 is turned off, and the control module 10 adjusts the first field effect transistor 11 to adjust the output voltage. When the first current is greater than or equal to the first threshold, the voltage conversion circuit switches to the second output mode, switch 13 is turned on, and the control module 10 outputs a switching signal to the first field effect transistor 11 and the second field effect transistor 12 to adjust the output voltage.

[0054] Specifically, the first output mode may specifically be a low dropout regulator (LDO) mode, and the second output mode may specifically be a PWM mode.

[0055] Specifically, when the first current is less than the first threshold, it can be considered that the load mode of the voltage conversion circuit is a light load mode. At this time, the voltage conversion circuit can switch to the first output mode. When the voltage conversion circuit is in the first output mode, the switch control module 14 can control switch 13 to turn off, and the control module 10 can control the first pole and the second pole of the first field effect transistor 11 to conduct and maintain the conducting state. At the same time, the control module 10 can also adjust the conduction voltage drop of the first field effect transistor 11 with reference to the real-time output voltage fed back by the feedback module 17 to adjust the power supply output port 200 to stably output the output voltage.

[0056] In practical applications, since the first field effect transistor 11 maintains the conducting state, the control module 10 does not need to send a switching signal to the first field effect transistor 11 and the second field effect transistor 12, and the first field effect transistor 11 and the second field effect transistor 12 also have no switching function. The current flowing through the power inductor 15 is direct current, and there is no repeated charging and discharging process on the power inductor 15. Therefore, the electromagnetic interference generated by the voltage conversion circuit in the light load mode is extremely small, improving the usage experience of the electronic device.

[0057] Specifically, when the first current is greater than or equal to the first threshold, it can be considered that the load mode of the voltage conversion circuit is a heavy load mode. At this time, the voltage conversion circuit can switch to the second output mode. When the voltage conversion circuit switches to the second output mode, the switch control module 14 can control switch 13 to turn on to turn on the first field effect transistor 11 and the second field effect transistor 12.

[0058] In practical applications, when the first field-effect transistor 11 and the second field-effect transistor 12 are turned on, the control module 10 can output switching signals to the first field-effect transistor 11 and the second field-effect transistor 12 with reference to the real-time output voltage fed back by the feedback module 17, so as to adjust the duty cycles of the first field-effect transistor 11 and the second field-effect transistor 12, and adjust the power output port 200 to stably output the output voltage.

[0059] with reference to Figure 2 , which shows a schematic structural diagram of another voltage conversion circuit according to an embodiment of the present application, as Figure 2 shown, the switch control module 14 may specifically include: a sampling device 141, a digital-to-analog conversion device 142, a reference voltage source 143, and a voltage comparator 144; wherein, the sampling device 141 is connected between the second pole of the first field-effect transistor 11 and the power output port 200; one end of the digital-to-analog conversion device 142 is connected to the sampling device 141, and the other end of the digital-to-analog conversion device 142 is connected to the first end of the voltage comparator 144; the reference voltage source 143 is connected to the second end of the voltage comparator 144; the third end of the voltage comparator 144 is connected to both the switch 13 and the control module 10.

[0060] Specifically, the sampling device 141 can be used to collect the first current, and the digital-to-analog conversion device 142 can calculate a first voltage according to the first current and the resistance value of the sampling device 141, and the first voltage is positively correlated with the first current. Since the third end of the voltage comparator 144 is connected to both the digital-to-analog conversion device 142 and the reference voltage source 143, the voltage comparator 144 can compare the first voltage with a preset voltage preset in the reference voltage source 143.

[0061] In practical applications, the preset voltage preset in the reference voltage source 143 can be the first voltage obtained by the digital-to-analog conversion device 142 after calculation when the first current is equal to the first threshold. That is, when the first current collected by the sampling device 141 is equal to the first threshold, the first voltage calculated by the digital-to-analog conversion device 142 is equal to the preset voltage in the reference voltage source 143. When the first current collected by the sampling device 141 is greater than the first threshold, the first voltage calculated by the digital-to-analog conversion device 142 is correspondingly greater than the preset voltage in the reference voltage source 143. When the first current collected by the sampling device 141 is less than the first threshold, the first voltage calculated by the digital-to-analog conversion device 142 is correspondingly less than the preset voltage in the reference voltage source 143.

[0062] In an embodiment of the present application, the voltage comparator 144 may compare the magnitudes of the first voltage and the preset voltage. When the first voltage is less than the preset voltage, the load mode of the voltage conversion circuit is a light load mode. At this time, the voltage comparator 144 may output a low-level signal to the switch 13 and the control module 10, and the low-level signal may control the switch 13 to turn off. When receiving the low-level signal, the control module 10 may turn off the switch signal sent to the first field-effect transistor 11 and the second field-effect transistor 12. In this way, the voltage conversion circuit may be switched to the first output mode.

[0063] Correspondingly, when the first voltage is greater than or equal to the preset voltage, the load mode of the voltage conversion circuit is a heavy load mode. At this time, the voltage comparator 144 may output a high-level signal to the switch 13 and the control module 10, and the high-level signal may control the switch 13 to turn on. When receiving the high-level signal, the control module 10 may output a switch signal to the first field-effect transistor 11 and the second field-effect transistor 12 to adjust the duty cycles of the first field-effect transistor 11 and the second field-effect transistor 12. In this way, the voltage conversion circuit may be switched to the second output mode.

[0064] The following provides an example of Figure 2 the working process of the voltage conversion circuit shown.

[0065] First, after the power input port 100 of the voltage conversion circuit is powered on, the switch 13 is default not turned on. The sampling device 141 may sample the first current. At this time, the first current is small, the control module 10 does not output a switch signal, and the output mode of the voltage conversion circuit is the first output mode.

[0066] Then, as the first current rises, the sampling device 141 continuously samples the first current. The digital-to-analog conversion device 142 may calculate a first voltage based on the first current and the resistance value of the sampling device 141, and send the first voltage to the voltage comparator 144. The voltage comparator 144 may compare the first voltage with the preset pre-pressure voltage in the reference voltage source 143.

[0067] Next, when the first current rises to be greater than or equal to the first threshold, the first voltage is correspondingly greater than or equal to the preset voltage, and the load mode of the voltage conversion circuit switches to the heavy load mode. At this time, the voltage comparator 144 can output a high-level signal to the switch 13 and the control module 10, and the high-level signal can control the switch 13 to conduct. When the control module 10 receives the high-level signal, it can output switch signals to the first field-effect transistor 11 and the second field-effect transistor 12 to adjust the duty cycles of the first field-effect transistor 11 and the second field-effect transistor 12. In this way, the voltage conversion circuit can be switched to the second output mode.

[0068] Finally, as the operating mode of the load module switches, the first current may decrease. When the first current drops to be less than the first threshold, the load mode of the voltage conversion circuit is the light load mode. At this time, the voltage comparator 144 can output a low-level signal to the switch 13 and the control module 10, and the low-level signal can control the switch 13 to disconnect. When the control module 10 receives the low-level signal, it can turn off the switch signals sent to the first field-effect transistor 11 and the second field-effect transistor 12. In this way, the voltage conversion circuit can be switched to the first output mode, greatly reducing the electromagnetic interference generated by the voltage conversion circuit in the light load mode and improving the user experience of the electronic device.

[0069] Optionally, the voltage conversion circuit may further include: a capacitor 16. One end of the capacitor 16 is connected between the sampling device 141 and the power output port 200, and the other end of the capacitor 16 is grounded to play a filtering role and improve the quality of the output voltage output by the power output terminal.

[0070] In practical applications, since the capacitive reactance of the capacitor 16 is inversely proportional to the frequency of the voltage signal in the circuit and the capacitance of the capacitor 16, when the capacitance value of the capacitor 16 is fixed, the capacitive reactance to the high-frequency part in the voltage signal is lower, and it is easy to be grounded through the capacitor 16 to achieve the purpose of eliminating the high-frequency part and realizing the filtering effect.

[0071] As Figure 2 shown, the sampling device 141 is a sampling resistor. One end of the sampling resistor is connected to the second pole of the first field-effect transistor 11, and the other end is connected to the power output port 200. In practical applications, since the resistance value of the sampling resistor is relatively stable, the value of the first voltage calculated by the analog-to-digital conversion device 142 based on the sampling resistor and the first current is also relatively accurate. Therefore, the comparison result of the first voltage and the preset voltage in the reference voltage source 143 by the voltage comparator 144 is also relatively accurate. In this way, the control logic judgment of the voltage conversion circuit can be made more accurate.

[0072] AsFigure 2 As shown, the voltage conversion circuit may further include: a first power inductor 151, one end of the first power inductor 151 is connected to the second pole of the first field effect transistor 11, and the other end of the first power inductor 151 is connected to one end of the sampling resistor. The first power inductor 151 can achieve charging energy storage and discharging energy dissipation through repeated charging and discharging processes, and can also pass a direct current.

[0073] Referring to Figure 3 , a schematic structural diagram of another voltage conversion circuit according to an embodiment of the present application is shown. As Figure 3 shown, the sampling device 141 may be a second power inductor 152. One end of the second power inductor 152 is connected to the second pole of the first field effect transistor 11, and the other end is connected to the power output port 200. The second power inductor 152 can achieve charging energy storage and discharging energy dissipation through repeated charging and discharging processes, and can also pass a direct current..

[0074] In a specific application, when the sampling device 141 is the second power inductor 152, the digital-to-analog conversion device 142 may calculate the first voltage according to the resistance value of the second power inductor 152 and the first current collected on the second power inductor 152, so as to use the second power inductor 152 as the sampling device 141 of the switch control module 14. In this way, it is possible to avoid additionally providing a separate sampling device 141 in the voltage conversion circuit, so as to reduce the number of devices in the voltage conversion circuit and simplify the structure of the voltage conversion circuit.

[0075] In summary, the voltage conversion circuit according to the embodiment of the present application may at least have the following advantages:

[0076] In the embodiment of the present application, a switch is added between the first field effect transistor and the second field effect transistor, and the switch control module is connected between the first field effect transistor and the power output port to collect the first current. The first current can be used to evaluate the load condition of the voltage conversion circuit. When the first current is less than the first threshold, it can be considered that the voltage conversion circuit is in a light load mode. At this time, the switch control module can control the switch to disconnect, so as to disconnect the connection between the first field effect transistor and the second field effect transistor. The control module can achieve the purpose of adjusting the output voltage by adjusting the first field effect transistor, and there is no need to send switch signals to the first field effect transistor and the second field effect transistor. In this way, the electromagnetic interference generated by the voltage conversion circuit in the light load mode can be greatly reduced, and the use experience of the electronic device can be improved.

[0077] Referring to Figure 4, which shows a flowchart of the steps of a voltage conversion method according to an embodiment of the present application. The voltage conversion method can be applied to the voltage conversion circuit described in any of the above embodiments, such as Figure 4 As shown, the voltage conversion method may specifically include the following steps:

[0078] Step 401: Collect a first current between the first field-effect transistor and the power output port.

[0079] In an embodiment of the present application, the voltage conversion circuit may specifically include: a control module 10, a first field-effect transistor 11, a second field-effect transistor 12, a switch 13, and a switch control module 14; a first pole of the first field-effect transistor 11 is connected to the power input port 100, a second pole of the first field-effect transistor 11 is connected to the power output port 200, and a gate of the first field-effect transistor 11 is connected to the control module 10; one end of the switch 13 is connected to the second pole of the first field-effect transistor 11, the other end of the switch 13 is connected to a first pole of the second field-effect transistor 12, a gate of the second field-effect transistor 12 is connected to the control module 10, and a second pole of the second field-effect transistor 12 is grounded; one end of the switch control module 14 is connected between the second pole of the first field-effect transistor 11 and the power output port 200 for collecting the first current, and the other end of the switch control module 14 is respectively connected to the switch 13 and the control module 10.

[0080] Step 402: When the first current is less than a first threshold, the switch control block controls the switch to turn off.

[0081] In practical applications, the greater the power required by the load module, the greater the output voltage that the power output port 200 needs to output, and the greater the value of the first current. The first current is positively correlated with the power demand of the load module. Therefore, the first current can be used to evaluate the load condition of the voltage conversion circuit.

[0082] Specifically, when the first current is greater than or equal to the first threshold, it can be considered that the load device requires a large amount of power, and the load mode of the voltage conversion circuit is a heavy load mode. When the first current is less than the first threshold, it can be considered that the load device requires a small amount of power, and the load mode of the voltage conversion circuit is a light load mode.

[0083] In the embodiment of the present application, when the first current collected by the switch control module 14 is less than the first threshold, it can be considered that the load mode of the voltage conversion circuit is a light load mode. At this time, the switch control module 14 can output a switch control signal to the switch 13, and the switch control signal can control the switch 13 to disconnect, so as to disconnect the connection between the first field effect transistor 11 and the second field effect transistor 12. At the same time, the switch control module 14 can also transmit the switch control signal to the control module 10.

[0084] Step 403: The control module adjusts the first field effect transistor to adjust the output voltage.

[0085] In the embodiment of the present application, when the load mode is a light load mode, in response to the switch control signal, the control module 10 can control the first pole and the second pole of the first field effect transistor 11 to conduct and maintain the conducting state. The control module 10 can achieve the purpose of adjusting the output voltage VOUT by adjusting the conduction voltage drop VMOS of the first field effect transistor 11. Moreover, since the first field effect transistor 11 maintains the conducting state, the control module 10 does not need to send switch signals to the first field effect transistor 11 and the second field effect transistor 12, and the first field effect transistor 11 and the second field effect transistor 12 also have no switching function. Therefore, the electromagnetic interference generated by the voltage conversion circuit in the light load mode can be greatly reduced, and the use experience of the electronic device can be improved.

[0086] In summary, the voltage conversion method described in the embodiment of the present application can at least include the following advantages:

[0087] In the embodiment of the present application, by adding a switch between the first field effect transistor and the second field effect transistor and connecting the switch control module between the first field effect transistor and the power output port to collect the first current, the first current can be used to evaluate the load condition of the voltage conversion circuit. When the first current is less than the first threshold, it can be considered that the voltage conversion circuit is in the light load mode. At this time, the switch control module can control the switch to disconnect to disconnect the connection between the first field effect transistor and the second field effect transistor. The control module can achieve the purpose of adjusting the output voltage by adjusting the first field effect transistor, and there is no need to send switch signals to the first field effect transistor and the second field effect transistor. In this way, the electromagnetic interference generated by the voltage conversion circuit in the light load mode can be greatly reduced, and the use experience of the electronic device can be improved.

[0088] The embodiment of the present application also provides an electronic device, which may specifically include the above voltage conversion circuit. The electronic device may include, but is not limited to, any one of a mobile phone, a tablet computer, and a wearable device. The embodiment of the present application does not make a specific limitation on the type of the electronic device.

[0089] It should be noted that in the embodiments of the present application, the structure of the voltage conversion circuit is the same as that of the voltage conversion circuits in the above embodiments, and its working principle and beneficial effects are also similar, so they will not be elaborated here.

[0090] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0091] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A voltage conversion circuit, characterized in that, The voltage conversion circuit includes: a control module, a first field-effect transistor, a second field-effect transistor, a switch, and a switch control module; A first pole of the first field-effect transistor is connected to a power input port, a second pole of the first field-effect transistor is connected to a power output port, and a gate of the first field-effect transistor is connected to the control module; One end of the switch is connected to the second pole of the first field-effect transistor, the other end of the switch is connected to a first pole of the second field-effect transistor, a gate of the second field-effect transistor is connected to the control module, and a second pole of the second field-effect transistor is grounded; One end of the switch control module is connected between the second pole of the first field-effect transistor and the power output port for collecting a first current, and the other end of the switch control module is respectively connected to the switch and the control module; When the first current is less than a first threshold, the switch control module controls the switch to disconnect, so as to disconnect the connection between the first field-effect transistor and the second field-effect transistor, and the control module adjusts the first field-effect transistor to adjust the output voltage of the power output port; When the first current is greater than or equal to the first threshold, the switch control module controls the switch to conduct, and the control module outputs a switching signal to the first field-effect transistor and the second field-effect transistor to adjust the duty cycles of the first field-effect transistor and the second field-effect transistor, so as to adjust the output voltage of the power output port.

2. The voltage conversion circuit according to claim 1, wherein The voltage conversion circuit includes a first output mode and a second output mode; wherein, When the first current is less than the first threshold, the voltage conversion circuit switches to the first output mode, the switch disconnects, and the control module adjusts the first field-effect transistor to adjust the output voltage; When the first current is greater than or equal to the first threshold, the voltage conversion circuit switches to the second output mode, the switch conducts, and the control module outputs a switching signal to the first field-effect transistor and the second field-effect transistor to adjust the output voltage.

3. The voltage conversion circuit according to claim 1, wherein The switch control module includes: a sampling device, a digital-to-analog conversion device, a reference voltage source, and a voltage comparator; wherein, The sampling device is connected between the second pole of the first field-effect transistor and the power output port; One end of the digital-to-analog conversion device is connected to the sampling device, and the other end of the digital-to-analog conversion device is connected to a first end of the voltage comparator; The reference voltage source is connected to a second end of the voltage comparator; A third end of the voltage comparator is connected to both the switch and the control module.

4. The voltage conversion circuit according to claim 3, wherein The sampling device is a sampling resistor, one end of the sampling resistor is connected to the second pole of the first field-effect transistor, and the other end is connected to the power output port.

5. The voltage conversion circuit according to claim 4, wherein [[ID=!5]]The voltage conversion circuit further includes: a first power inductor, one end of the first power inductor is connected to the second pole of the first field-effect transistor, and the other end of the first power inductor is connected to one end of the sampling resistor.

6. The voltage conversion circuit according to claim 3, wherein The sampling device is a second power inductor, one end of the second power inductor is connected to the second pole of the first field effect transistor, and the other end is connected to the power output port.

7. The voltage conversion circuit according to claim 4, characterized in that The voltage conversion circuit further includes: a capacitor, one end of the capacitor is connected between the sampling device and the power output port, and the other end of the capacitor is grounded.

8. The voltage conversion circuit according to claim 1, wherein The voltage conversion circuit further includes: a feedback module, one end of the feedback module is connected between the second pole of the first field effect transistor and the power output port, and the other end of the feedback module is connected to the control module.

9. A voltage conversion method, characterized in that The voltage conversion method is applied to the voltage conversion circuit according to any one of claims 1 to 8; the voltage conversion method includes: Collecting a first current between the first field effect transistor and the power output port; When the first current is less than a first threshold, the switch control module controls the switch to be turned off; The control module adjusts the first field effect transistor to adjust the output voltage.

10. An electronic device, characterized in that, The electronic device includes: the voltage conversion circuit according to any one of claims 1 to 8.

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