Power supply circuit and electronic equipment

Abstract

The invention discloses a power supply circuit which comprises a power supply unit, a sampling unit and a control unit. The power supply unit is used for providing output voltage, the power supply unit comprises a plurality of power supply sub units which are connected in parallel, and the output ends of the power supply sub units are electrically connected; the sampling unit is used for collecting load current output by the output end of the power supply circuit; the control unit is used for controlling the working state of at least one power supply sub-unit according to the load current, and the working state comprises a power supply state and a non-power supply state.

Description

Technical Field

[0001] This application relates to the field of electronic technology, and to a power supply circuit and electronic device that outputs a stable voltage across a variety of load current ranges. Background Technology

[0002] Power Supply Rejection Ratio (PSRR) is a core performance indicator that measures the ability of electronic circuits to suppress power supply voltage fluctuations. It describes the circuit's "anti-interference capability" in resisting interference from power supply voltage variations. A higher absolute PSRR value indicates a stronger ability to suppress ripple. PSRR typically varies with frequency, exhibiting different values ​​at different frequencies, and is usually expressed in decibels (dB). It is affected by factors such as load current and output capacitance. Under light loads, the PSRR of an LDO is generally better than under heavy loads; under heavy loads, the output stage gain decreases, leading to a drop in PSRR at high frequencies. The type and value of the output capacitor also affect PSRR at high frequencies. To obtain better PSRR at certain frequencies, it is usually necessary to use output capacitors with appropriate capacitance and low ESR (equivalent series resistance).

[0003] With the continuous development of electronic technology, electronic devices such as mobile phones and IoT products may have two or more operating current ranges for certain loads. In some linear circuits, when the load current exceeds the rated value, the power supply rejection ratio (PSRR) drops rapidly, leading to increased power supply voltage ripple and affecting the stability of downstream analog devices. For example, the load current of the AVDD power supply for a camera varies in different scenarios, ranging from tens to hundreds of milliamps. The power supply unit's PSRR may differ by more than 10% under different operating states in continuous conduction mode (CCM), resulting in increased power supply ripple and affecting camera stability. Summary of the Invention

[0004] This application provides a power supply circuit and electronic device that can suppress ripples within a variety of load current ranges, meeting the usage requirements of electronic devices in various scenarios.

[0005] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0006] In a first aspect, a power supply circuit is provided, comprising: a power supply unit, a sampling unit, and a control unit; the power supply unit is used to provide an output voltage, and the power supply unit includes multiple power supply units connected in parallel, the output terminals of the multiple power supply units being electrically connected; the sampling unit is used to collect the load current output from the output terminal of the power supply circuit; the control unit is used to control the operating state of at least one power supply unit according to the load current, the operating state including a power supply state and a non-power supply state.

[0007] Secondly, this application provides an electronic device, which includes the power supply circuit described above.

[0008] The technical solution adopted in this application can achieve the following technical effects:

[0009] The power supply circuit disclosed in this application includes a power supply unit, a sampling unit, and a control unit. The power supply unit includes multiple power supply units connected in parallel, and the output terminals of the multiple power supply units are electrically connected. The sampling unit is used to collect the load current output from the output terminal of the power supply circuit. According to the range of the load current collected by the sampling unit, the control unit controls the power supply units to be in a power supply state or a non-power supply state. At least one power supply unit participates in power supply in the power supply circuit. The power supply circuit can automatically collect the load current through the sampling unit, and the control unit automatically switches an appropriate number of power supply units to operate in the power supply state according to the range of the load current collected by the sampling unit, so that the PSRR of the power supply circuit is kept in the peak range. When the load current is large, the control unit controls at least one power supply unit to switch to the power supply state, so that multiple power supply units participate in power supply in parallel, and the operating current of each power supply unit participating in power supply is within a suitable range, thereby keeping the PSRR of the power supply units participating in power supply in the peak range, ensuring that the power supply units participating in power supply can provide better ripple suppression effect at output, and improving the overall ripple suppression effect of the power supply circuit. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of a power supply circuit structure provided in an embodiment of this application;

[0011] Figure 2 This is a schematic diagram of a power supply circuit structure provided in an embodiment of this application;

[0012] Figure 3 This is a schematic diagram of another power supply circuit structure provided in the embodiments of this application;

[0013] Figure 4 This is a schematic diagram of another power supply circuit structure provided in the embodiments of this application;

[0014] Figure 5 This is a flowchart illustrating the process of an embodiment of this application;

[0015] Figure 6 This is a PSRR curve of the power supply unit provided in the embodiments of this application;

[0016] Figure 7 This is a PSRR curve diagram showing the number of power supply units when different quantities are provided in the embodiments of this application;

[0017] Figure 8This is a schematic diagram of an LDO circuit structure provided in an embodiment of this application.

[0018] Explanation of reference numerals in the attached figures:

[0019] 10-Power supply unit, 11-First power supply unit, 12-Second power supply unit, 13-Third power supply unit;

[0020] 20 - Sampling unit, 21 - Sampling resistor, 22 - Differential amplifier;

[0021] 30-Control unit, 31-Comparator, 31a-First comparator, 31b-Second comparator, 32-Switch, 32a-First switch, 32b-Second switch;

[0022] 40 - Power supply. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0024] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and are not limited in number; for example, a first object can be one or more.

[0025] In the description of this invention, it should be noted that, unless otherwise explicitly 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. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] This application provides a power supply circuit, such as Figure 1As shown, the circuit includes: a power supply unit 10, a sampling unit 20, and a control unit 30; the power supply unit 10 is used to provide the output voltage, and the power supply unit 10 includes multiple power supply units connected in parallel, and the output terminals of the multiple power supply units are electrically connected; the sampling unit 20 is used to collect the load current output from the output terminal of the power supply circuit; the control unit 30 is used to control the operating state of at least one power supply unit according to the load current, and the operating state of the power supply unit includes a power supply state and a non-power supply state.

[0027] like Figure 1 As shown, the power supply unit 10 includes a first power supply unit 11 and a second power supply unit 12 connected in parallel. One end of the first power supply unit 11 is connected to a power signal, and the other end is electrically connected to the sampling unit 20. The first end of the sampling unit 20 is electrically connected to the power supply unit 10, and the second end is connected to the output terminal of the power supply circuit. The output terminal of the sampling unit 20 is electrically connected to the input terminal of the control unit 30. The first end of the control unit 30 is connected to a power signal, and the second end is electrically connected to the second power supply unit 12. Optionally, the first end of the control unit 30 is electrically connected to the second power supply unit 12, and the second end is electrically connected to the sampling unit 20.

[0028] When the load current is large, the control unit 30 controls at least one power supply unit to switch to power supply mode, allowing multiple power supply units to participate in power supply in parallel. The operating current of each power supply unit is within a suitable range, ensuring that the PSRR of the participating power supply units is in the peak range. This ensures that the participating power supply units can provide better ripple suppression at output, improving the overall ripple suppression effect of the power supply circuit. The power supply unit 10 includes a first power supply unit 11 and a second power supply unit 12 connected in parallel. One end of the first power supply unit 11 is connected to a power signal. The other end of the first power supply unit 11 is connected to the load. When the power supply circuit is in power supply mode, the first power supply unit 11 is always in power supply mode, ensuring that the power supply circuit has the most basic power supply capability.

[0029] like Figure 1 As shown, at least one power supply unit in the power supply circuit is in a power supply state, such as... Figure 6 and Figure 7 As shown, as the load current increases, even exceeding the rated value, the PSRR of the power supply unit in the power supply state decreases, and the power supply ripple of the circuit increases, which is not conducive to the stable operation of the load. In this case, the control unit 30 controls the power supply unit to conduct with the power supply circuit, and multiple power supply units are connected in parallel to supply power. The load current shared by the power supply units participating in the power supply decreases, the PSRR of the power supply units participating in the power supply increases, and the power supply circuit's ability to suppress ripple is improved.

[0030] One end of the second power supply unit 12 is connected to a power signal via the control unit 30, and the other end of the second power supply unit 12 is connected to a load. When the load current exceeds a threshold, the control unit 30 controls the second power supply unit 12 to electrically connect to the power signal, thereby switching the second power supply unit 12 to the power supply state. Alternatively, one end of the second power supply unit 12 is connected to a power signal, and the other end of the second power supply unit 12 is connected to a load via the control unit 30. When the load current exceeds a threshold, the control unit 30 controls the second power supply unit 12 to electrically connect to the load, thereby switching the second power supply unit 12 to the power supply state.

[0031] When the load current does not reach the threshold, the first power supply unit 11 provides power directly. When the load current exceeds the threshold, the control unit 30 controls at least one second power supply unit 12 to switch to the power supply state. This ensures that the power supply circuit can provide a stable and reliable basic power supply capability, improves the reliability of the power supply circuit, and reduces the complexity of the control unit.

[0032] It is understood that in some specific embodiments, each power supply unit in the power supply unit 10 is connected to a power signal and / or load through the control unit 30. Each time the power supply unit 10 supplies power, the control unit 30 needs to control the working state of each power supply unit. No specific limitation is made here.

[0033] Optionally, the sampling unit 20 can directly output the sampled load current to the input terminal of the control unit 30, or the sampling unit 20 can amplify the sampled load current and then output it to the input terminal of the control unit 30. For example, a differential amplifier with a transconductance topology can be used to output the current signal to the input terminal of the control unit 30.

[0034] In some implementations, the sampling unit 20 obtains a sampling voltage signal based on the collected load current and outputs the sampling voltage signal to the input terminal of the control unit 30.

[0035] Specifically, such as Figure 2 As shown, the sampling unit 20 includes a sampling resistor 21. One end of the sampling resistor 21 is electrically connected to the output terminal of a plurality of power supply units, and the other end of the sampling resistor 21 is electrically connected to the output terminal of the power supply circuit to obtain the load current.

[0036] like Figure 1As shown, sampling unit 20 acquires the load current signal passing through sampling resistor 21. Power supply unit 10 includes multiple power supply units. One end of sampling resistor 21 is electrically connected to the output terminal of power supply unit 10, and the other end is electrically connected to the output terminal of the power supply circuit. That is, sampling unit 20 can acquire a sampling voltage signal based on the load current by acquiring the voltage difference formed by the load current flowing through sampling resistor 21. Sampling unit 20 outputs the acquired sampling voltage signal across sampling resistor 21 to the input terminal of control unit 30.

[0037] Furthermore, if the sampled voltage signal is too small, the sampling unit 20 can amplify the acquired sampled voltage signal and output it to the input terminal of the control unit 30.

[0038] Specifically, such as Figure 2 , Figure 3 As shown, the sampling unit 20 also includes a differential amplifier 22. The first end of the differential amplifier 22 is connected to the first end of the sampling resistor 21, the second end of the differential amplifier 22 is connected to the second end of the sampling resistor 21, and the third end of the differential amplifier 22 is connected to the control unit 30.

[0039] Differential amplifier 22 is used to amplify the sampled voltage signal obtained through sampling resistor 21. The magnitude of the sampled voltage signal is positively correlated with the magnitude of the load current.

[0040] Optionally, the first terminal of the differential amplifier 22 is the non-inverting input terminal, the second terminal of the differential amplifier 22 is the inverting input terminal, and the third terminal of the differential amplifier 22 is the output terminal. Alternatively, the first terminal of the differential amplifier 22 is the inverting input terminal, the second terminal of the differential amplifier 22 is the non-inverting input terminal, and the third terminal of the differential amplifier 22 is the output terminal.

[0041] In some embodiments, such as Figures 2 to 4 As shown, the control unit 30 includes a comparator 31. The first input terminal of the comparator 31 is electrically connected to the sampling unit 20 to obtain the load current or a load signal generated based on the load current. The second input terminal of the comparator 31 receives a reference signal, and the output terminal of the comparator 31 is electrically connected to the power supply unit. The comparator 31 controls the on / off state of the power supply unit according to the magnitude of the load current to adjust the number of power supply units in the power supply circuit that are in the power supply state.

[0042] When the load signal generated based on the load current is a current signal, the sampling unit 20 outputs either the load current or a current signal generated based on the load current. Correspondingly, the reference signal input to the second input terminal of the comparator 31 is a reference current signal. When the sampling unit 20 directly outputs the load current, the comparator 31 controls the on / off state of the power supply unit according to the magnitude of the load current. When the sampling unit 20 outputs a current signal generated based on the load current, since the magnitude of the current signal is positively correlated with the magnitude of the load current, the comparator 31 can control the operating state of the power supply unit according to the magnitude of the load current through the current signal. The comparator 31 controls the operating state of the power supply unit according to the magnitude of the load current to adjust the number of power supply units in the power supply circuit that are in the power supply state, including:

[0043] Comparator 31 compares the magnitude of the load current or the current signal generated based on the load current with the reference current signal. If the load current or the current signal generated based on the load current is greater than the reference current signal, it controls the power supply unit connected to comparator 31 to switch to the power supply state, so as to adjust the number of power supply units in the power supply circuit that are in the power supply state.

[0044] When the load signal generated based on the load current is a voltage signal, the sampling unit 20 outputs a voltage signal generated based on the load current. Correspondingly, the reference signal input to the second input terminal of the comparator 31 is a voltage signal. When the sampling unit outputs a voltage signal generated based on the load current, since the magnitude of the voltage signal is positively correlated with the magnitude of the load current, the comparator 31 can control the operating state of the power supply unit according to the magnitude of the load current through the voltage signal. The comparator 31 controls the operating state of the power supply unit according to the magnitude of the load current to adjust the number of power supply units in the power supply circuit that are in the power supply state, including: the comparator 31 compares the magnitude relationship between the voltage signal generated based on the load current and the reference voltage signal; when the voltage signal generated based on the load current is greater than the reference voltage signal, it controls the power supply unit connected to the comparator 31 to switch to the power supply state to adjust the number of power supply units in the power supply circuit that are in the power supply state.

[0045] Optionally, the first input terminal of comparator 31 is a non-inverting input terminal, and the second input terminal of comparator 31 is an inverting input terminal. Alternatively, the first input terminal of comparator 31 is an inverting input terminal, and the second input terminal of comparator 31 is a non-inverting input terminal.

[0046] Furthermore, such as Figure 2As shown, the power supply circuit also includes a power supply 40 for providing power signals, and the control unit 30 also includes a switch 32. The first end of the switch 32 is electrically connected to the power supply 40, the second end of the switch 32 is connected to the input end of the power supply unit, and the control end of the switch 32 is connected to the output end of the comparator 31. The comparator 31 controls the on / off state of the switch 32 according to the magnitude of the load current, thereby switching the working state of the power supply unit.

[0047] Specifically, such as Figure 2 As shown, the power supply unit includes a first power supply unit 11 and a second power supply unit 12. The output terminals of both the first power supply unit 11 and the second power supply unit 12 are electrically connected to the output terminal of the power supply circuit to supply power to the load. When the load current is greater than a first threshold, the output terminal of comparator 31 outputs a high level, switch 32 is turned on, connecting the second power supply unit 12 to the power supply 40, and the second power supply unit switches to the power supply state. The first power supply unit 11 and the second power supply unit 12 are connected in parallel to participate in the power supply. When the load current is less than the first threshold, the output terminal of comparator 31 outputs a low level, switch 32 is turned off, the second power supply unit 12 is disconnected from the power supply, and the second power supply unit switches to the non-power supply state.

[0048] Optionally, such as Figure 4 As shown, the power supply circuit also includes a power supply 40 for providing a power signal, which is electrically connected to the input terminal of the power supply unit 10; the power supply unit has an enable terminal, and the output terminal of the comparator 31 is connected to the enable terminal. The comparator 31 controls the enable signal input to the enable terminal according to the magnitude of the load current, thereby switching the working state of the power supply unit.

[0049] Specifically, the power supply unit is integrated into the power supply chip. The power supply chip has an enable pin for controlling its operating state. The output of comparator 31 is electrically connected to the enable pin of the power supply unit, that is, the output of comparator 31 is electrically connected to the enable pin of the power supply chip. When the load current is greater than a first threshold, the output of comparator 31 outputs a first enable signal to the enable pin of the connected power supply chip, enabling the power supply chip to switch to a power supply state, causing the power supply chip, as the power supply unit, to output a power supply signal to the load. When the load current is less than the first threshold, the output of comparator 31 outputs a second enable signal to the enable pin of the connected power supply chip, enabling the power supply chip to switch to a non-power supply state, causing the power supply chip, as the power supply unit, to stop outputting a power supply signal to the load. Using a power supply unit with an enable pin instead of a switch-based power supply unit results in a faster response speed and facilitates circuit integration.

[0050] Optionally, the first enable signal is a high-level signal, and the second enable signal is a low-level signal. It is understood that the first enable signal can also be a low-level signal, and the second enable signal can also be a high-level signal; no specific limitation is made here.

[0051] In some embodiments, such as Figure 2 , Figure 3 , Figure 4 , Figure 7 As shown, the power supply unit 10 includes a first power supply unit 11 and a second power supply unit 12 connected in parallel. The output terminals of the first power supply unit 11 and the second power supply unit 12 are connected to one end of the sampling resistor 21 of the sampling unit 20, and the other end of the sampling resistor 21 is connected to the output terminal of the power supply circuit. The control unit 30 includes a first comparator 31a. The first terminal of the first comparator 31a is electrically connected to the output terminal of the sampling unit 20, the second terminal of the first comparator 31a is connected to a first reference signal, and the output terminal of the first comparator 31a is electrically connected to the second power supply unit 12. When the load current is greater than a first threshold, the first comparator 31a controls the second power supply unit 12 to operate in the power supply state, and the first power supply unit 11 and the second power supply unit 12 jointly supply power. When the load current is less than the first threshold, the first comparator 31a controls the second power supply unit 12 to operate in the non-power supply state, and the first power supply unit 11 supplies power.

[0052] like Figure 3 , Figure 4 , Figure 7As shown, when the first comparator 31a determines that the load current is less than the first threshold, the first comparator 31a outputs a first signal to control the second power supply unit 12 to be in a non-powered state. The load is powered by the first power supply unit 11, and the PSRR of the power supply circuit follows the first curve. When the load current is less than the first threshold, the PSRR of the power supply circuit remains in the peak range. When the load current is greater than the first threshold, the PSRR of the power supply circuit decreases significantly. When the comparator 31a determines that the load current is greater than the first threshold, the first comparator 31a outputs a second signal to control the second power supply unit 12 to switch to a power supply state. The first power supply unit 11 and the second power supply unit 12 are connected in parallel to participate in the power supply. At this time, the PSRR of the power supply circuit follows the second curve. When the load current is less than the first threshold, the PSRR of the power supply circuit remains in the peak range. When the load current is greater than the first threshold but less than the second threshold, the PSRR of the power supply circuit still remains in the peak range. When the load current is greater than the second threshold, the PSRR of the power supply circuit decreases significantly. The parallel connection of the first power supply unit 11 and the second power supply unit 12 in the power supply circuit ensures that the PSRR of the power supply circuit remains in the peak range when the load current is greater than the first threshold and less than the second threshold, thus maintaining a good ability to suppress ripple and improving the working stability of the load connected to the power supply circuit.

[0053] Furthermore, such as Figure 3 , Figure 4 , Figure 7As shown, the power supply unit 10 also includes a third power supply unit 13 connected in parallel with the first power supply unit 11 and the second power supply unit 12. The output terminal of the third power supply unit 13 is connected to the sampling resistor 21. The control unit 30 also includes a second comparator 31b. The first terminal of the second comparator 31b is electrically connected to the output terminal of the sampling unit 20, and the second terminal of the second comparator 31b is connected to the second reference signal. The output terminal of the first comparator 31a is electrically connected to the second power supply unit 12. When the load current is greater than the second threshold and the second threshold is greater than the first threshold, the first comparator 31a controls the second power supply unit 12 to operate in the power supply state, and the second comparator 31b controls the third power supply unit 13 to operate in the power supply state. In the first power supply unit 11, the second power supply unit 12, and the third power supply unit 13 jointly supply power. When the load current is less than the second threshold and less than the first threshold, the first comparator 31a controls the second power supply unit 12 to operate in a non-power supply state, the second comparator 31b controls the third power supply unit 13 to operate in a non-power supply state, and the first power supply unit 11 supplies power. When the load current is less than the second threshold and greater than the first threshold, the first comparator 31a controls the second power supply unit 12 to operate in a power supply state, the second comparator 31b controls the third power supply unit 13 to operate in a non-power supply state, and the first power supply unit 11 and the second power supply unit 12 jointly supply power.

[0054] like Figure 3 , Figure 4 , Figure 7As shown, when the first comparator 31a determines that the load current is less than the first threshold, the first comparator 31a outputs a first signal to control the second power supply unit 12 and the third power supply unit 13 to work in a non-power supply state. The load is powered by the first power supply unit 11. The PSRR of the power supply circuit is the first curve. When the load current is less than the first threshold, the PSRR of the power supply circuit remains in the peak range. When the load current is greater than the first threshold, the PSRR of the power supply circuit is significantly reduced. When the first comparator 31a determines that the load current is greater than the first threshold and the second comparator 31b determines that the load current is less than the second threshold, the first comparator 31a outputs a second signal to control the second power supply unit 12 to operate in the power supply state, and the second comparator 31b outputs a first signal to control the third power supply unit 13 to operate in the non-power supply state. The first power supply unit 11 and the second power supply unit 12 are connected in parallel to participate in the power supply. At this time, the PSRR of the power supply circuit is the second curve. When the load current is less than the first threshold, the PSRR of the power supply circuit remains in the peak range. When the load current is greater than the first threshold and less than the second threshold, the PSRR of the power supply circuit still remains in the peak range. When the load current is greater than the second threshold, the PSRR of the power supply circuit decreases significantly. When the first comparator 31a determines that the load current is greater than the first threshold and the second comparator 31b determines that the load current is greater than the second threshold, the first comparator 31a outputs a second signal to control the second power supply unit 12 to operate in the power supply state, and the second comparator 31b outputs a second signal to control the third power supply unit 13 to operate in the power supply state. The first power supply unit 11, the second power supply unit 12, and the third power supply unit 13 are connected in parallel to participate in the power supply. At this time, the PSRR of the power supply circuit is the third curve. When the load current is less than the first threshold, the PSRR of the power supply circuit remains in the peak range. When the load current is greater than the first threshold but less than the second threshold, the PSRR of the power supply circuit remains in the peak range. When the load current is greater than the second threshold, the PSRR of the power supply circuit still remains in the peak range. With the first power supply unit 11, the second power supply unit 12, and the third power supply unit 13 included in the power supply circuit, the PSRR of the power supply circuit remains in the peak range even when the load current is greater than the second threshold, maintaining good ripple suppression capability, resulting in small load current fluctuations and improving the working stability of the load connected to the power supply circuit.

[0055] Optionally, the first signal is a low-level signal and the second signal is a high-level signal. Alternatively, the first signal is a high-level signal and the second signal is a low-level signal; this is not limited here.

[0056] Optionally, the power supply circuit may also include multiple power supply units, such as a fourth power supply unit. The control unit 30 controls different numbers of power supply units to conduct to adapt to different load currents, thereby maintaining the load current shared by the power supply units within the peak range of PSRR. This application does not limit the number of power supply units.

[0057] In some embodiments, the power supply circuit further includes a power supply 40 for providing a power signal, wherein when the power supply unit is in a powered state, the input terminal of the power supply unit is electrically connected to the power supply 40.

[0058] LDO (Low Dropout Regulator) is a power management chip that can stably output a fixed voltage even when the difference between the input and output voltage is small. Types include PMOS, NMOS, and traditional PNP / NPN. The difference between an LDO and a DC-DC converter is that the LDO has a simpler circuit and lower output ripple, but lower efficiency. LDOs are widely used in AC / DC conversion, battery power supply, and switching power supply circuits, and are commonly used power management chips in mobile phones. PSRR (Power Suppression Ripple) is the LDO's ability to suppress input power supply ripple; it quantifies how much input ripple is transmitted to the output through the LDO. Mathematically, it is expressed as PSRR = 20 × lg(Vin_ripple / Vout_ripple (unit: dB). PSRR is a key indicator of an LDO's ability to suppress input power supply ripple and noise. It represents the degree of ripple attenuation at the LDO's output relative to the input; a higher value indicates stronger suppression capability. A high PSRR ensures a stable output voltage for the LDO, which is particularly important in analog circuits requiring low noise (such as sensors, ADCs / DACs). Therefore, for devices with high power supply ripple requirements, an LDO is often connected in series after the DC / DC converter to further filter out the ripple generated by the DC / DC converter.

[0059] In some embodiments, the power supply unit includes an LDO power supply circuit.

[0060] Optionally, the LDO power supply circuit includes the LDO power supply circuit in the camera module of the electronic device. It is understood that the power supply unit 10 includes multiple power supply units, that is, the power supply unit 10 includes multiple LDO power supply circuits from camera modules. The LDO power supply circuits of multiple cameras are connected in parallel to form the power supply unit 10. By reusing the existing LDO power supply circuits in the device, no additional components are needed, thus reducing costs.

[0061] Optionally, the power supply unit includes an LDO power supply circuit, which is connected in parallel with the LDO power supply circuit in the camera module. The output terminal of the LDO power supply circuit is connected to the output terminal of the power supply unit. The output terminal of the LDO power supply circuit is also connected to the output terminal of the LDO power supply circuit in the camera module.

[0062] Specifically, such as Figure 3 and Figure 4 As shown, the first power supply unit 11 is the first LDO power supply circuit, the second power supply unit 12 is the second LDO power supply circuit, and the third power supply unit 13 is the third LDO power supply circuit. The first LDO power supply circuit, the second LDO power supply circuit, and the third LDO power supply circuit are respectively applied to the first camera, the second camera, and the third camera, and the output voltages of the first LDO power supply circuit, the second LDO power supply circuit, and the third LDO power supply circuit are the same.

[0063] Alternatively, in some embodiments, the power supply circuit is composed of discrete components and does not require the use of analog-to-digital converter (ADC) resources built into the system-on-a-chip (SoC).

[0064] This application also provides an electronic device, which includes the power supply circuit described above.

[0065] The electronic devices disclosed in this application can be smartphones, tablets, e-book readers, wearable devices (such as smartwatches and VR glasses), video game consoles, walkie-talkies, etc., or other devices with high power ripple requirements, such as headphones and cameras. This application does not limit the specific types of electronic devices.

[0066] The above embodiments of the present invention focus on describing the differences between the various embodiments. As long as the different optimization features of the various embodiments are not contradictory, they can be combined to form a better embodiment. For the sake of brevity, they will not be described in detail here.

[0067] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of the present invention.

Claims

1. A power supply circuit, characterized in that, include: Power supply unit, sampling unit, control unit; The power supply unit is used to provide the output voltage. The power supply unit includes multiple power supply units connected in parallel, and the output terminals of the multiple power supply units are electrically connected. The sampling unit is used to collect the load current output from the output terminal of the power supply circuit; The control unit is used to control the operating state of at least one of the power supply units according to the load current, the operating state including a power supply state and a non-power supply state.

2. The circuit according to claim 1, characterized in that, The sampling unit includes a sampling resistor, one end of which is electrically connected to the output terminals of the plurality of power supply units, and the other end of which is electrically connected to the output terminal of the power supply circuit to obtain the load current.

3. The circuit according to claim 2, characterized in that, The sampling unit further includes a differential amplifier, the first terminal of which is connected to the first terminal of the sampling resistor, and the second terminal of the differential amplifier is connected to the second terminal of the sampling resistor. The third terminal of the differential amplifier is connected to the control unit.

4. The power supply circuit according to claim 1, characterized in that, The control unit includes a comparator. The first input terminal of the comparator is electrically connected to the sampling unit to obtain the load current or a load signal generated based on the load current. The second input terminal of the comparator receives a reference signal. The output terminal of the comparator is electrically connected to the power supply unit. The comparator controls the operating state of the power supply unit according to the magnitude of the load current, so as to adjust the number of power supply units in the power supply circuit that are in the power supply state.

5. The power supply circuit according to claim 4, characterized in that, It also includes a power supply for providing a power signal; the control unit also includes a switch, the first end of which is electrically connected to the power supply, the second end of which is connected to the input end of the power supply unit, and the control end of which is connected to the output end of the comparator. The comparator controls the switching on and off of the switch according to the magnitude of the load current, thereby switching the operating state of the power supply unit.

6. The power supply circuit according to claim 4, characterized in that, It also includes a power supply for providing a power signal, the power supply being electrically connected to the input terminal of the power supply unit; the power supply unit has an enable terminal, the output terminal of the comparator is connected to the enable terminal, and the comparator controls the enable signal input to the enable terminal according to the magnitude of the load current, thereby switching the operating state of the power supply unit.

7. The circuit according to claim 1, characterized in that, The power supply unit includes a first power supply unit and a second power supply unit connected in parallel. The output terminals of the first power supply unit and the second power supply unit are connected to one end of the sampling resistor of the sampling unit, and the other end of the sampling resistor is connected to the output terminal of the power supply circuit. The control unit includes a first comparator, a first terminal of which is electrically connected to the output terminal of the sampling unit, a second terminal of which is connected to a first reference signal, and an output terminal of which is electrically connected to the second power supply unit. When the load current is greater than the first threshold, the first comparator controls the second power supply unit to operate in the power supply state, and the first power supply unit and the second power supply unit jointly supply power. When the load current is less than the first threshold, the first comparator controls the second power supply unit to operate in a non-powered state, and the first power supply unit is powered.

8. The circuit according to claim 7, characterized in that, The power supply unit further includes a third power supply unit connected in parallel with the first power supply unit and the second power supply unit, and the output terminal of the third power supply unit is connected to the sampling resistor; The control unit further includes a second comparator, the first terminal of which is electrically connected to the output terminal of the sampling unit, the second terminal of which is connected to a second reference signal, and the output terminal of the first comparator is electrically connected to the second power supply unit. When the load current is greater than the second threshold and the second threshold is greater than the first threshold, the first comparator controls the second power supply unit to operate in the power supply state, the second comparator controls the third power supply unit to operate in the power supply state, and the first power supply unit, the second power supply unit and the third power supply unit jointly supply power. When the load current is less than the second threshold and the load current is less than the first threshold, the first comparator controls the second power supply unit to operate in a non-powered state, the second comparator controls the third power supply unit to operate in a non-powered state, and the first power supply unit supplies power. When the load current is less than the second threshold and the load current is greater than the first threshold, the first comparator controls the second power supply unit to operate in the power supply state, the second comparator controls the third power supply unit to operate in the non-power supply state, and the first power supply unit and the second power supply unit jointly supply power.

9. The circuit according to any one of claims 1 to 8, characterized in that, It also includes a power supply for providing a power signal, wherein, when the power supply unit is in a powered state, the input terminal of the power supply unit is electrically connected to the power supply; and / or The power supply unit includes an LDO power supply circuit.

10. An electronic device, characterized in that, The electronic device includes a power supply circuit as described in any one of claims 1 to 9.

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