Power supply circuit, control method and electronic equipment

Abstract

The present invention provides, for example, a power supply circuit having improved conversion efficiency. The power supply circuit includes: a voltage conversion circuit that converts an input voltage; a first power storage element for smoothing the output of the voltage conversion circuit; a bidirectional voltage conversion circuit, the output side of which is connected in parallel with the first power storage element; and a second power storage element connected to an input side of the bidirectional voltage conversion circuit, in which the voltage conversion circuit performs control such that a voltage of the second power storage element becomes a second voltage value, and the bidirectional voltage conversion circuit performs control such that a voltage of the first power storage element becomes a first voltage value.

Description

Technical Field

[0001] The present disclosure relates to a power supply circuit, a control method, and an electronic device. Background Art

[0002] For example, the power supply circuits described in Patent Documents 1 and 2 are referred to as power supply circuits connected to a load.

[0003] Citation List

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2022-11203

[0006] Patent Document 2: Japanese Patent Application Laid-Open No. 2014-90622 Summary of the Invention

[0007] Technical Problem

[0008] In this field, from the viewpoint of environmental friendliness, it is desired to improve the conversion efficiency of the power supply circuit in order to reduce the power consumption of the electronic device.

[0009] An object of the present disclosure is to provide a power supply circuit having improved conversion efficiency, a control method for the power supply circuit, and an electronic device using the power supply circuit.

[0010] Solution to the Problem

[0011] The present disclosure is, for example, a power supply circuit including:

[0012] A voltage conversion circuit that converts an input voltage;

[0013] A first energy storage element that smoothes the output of the voltage conversion circuit;

[0014] A bidirectional voltage conversion circuit whose output side is connected in parallel with the first energy storage element; and

[0015] A second energy storage element that is connected to the input side of the bidirectional voltage conversion, where

[0016] The voltage conversion circuit controls the voltage of the second energy storage element to have a second voltage value, and

[0017] The bidirectional voltage conversion circuit controls the voltage of the first energy storage element to have a first voltage value.

[0018] The present disclosure may be an electronic device including the above power supply circuit.

[0019] The present disclosure is, for example, a control method including:

[0020] Convert the input voltage through a voltage conversion circuit;

[0021] Smooth the output of the voltage conversion circuit through a first energy storage element;

[0022] Control the voltage of the first energy storage element to have a first voltage value through a bidirectional voltage conversion circuit, the output side of the bidirectional voltage conversion circuit is connected in parallel with the first energy storage element, and the input side of the bidirectional voltage conversion circuit is connected to a second energy storage element; and

[0023] Control the voltage of the second energy storage element to have a second voltage value through a voltage conversion circuit. Description of the Drawings

[0024] Figure 1 Is a diagram referred to when describing the problems to be considered in the present disclosure.

[0025] Figure 2 Is a diagram for describing a configuration example of a power supply circuit according to the first embodiment.

[0026] Figure 3 Is a diagram referred to when describing an operation example of the power supply circuit according to the first embodiment.

[0027] Figure 4 Is a diagram referred to when describing an operation example of the power supply circuit according to the first embodiment.

[0028] Figure 5 Is a diagram referred to when describing an operation example of the power supply circuit according to the second embodiment.

[0029] Figure 6 Is a diagram for describing an example of the present disclosure.

[0030] Figure 7 Is a diagram for describing an example of the present disclosure.

[0031] Figure 8 Is a diagram for describing a modification example. Detailed Description of the Invention

[0032] The embodiments of the present disclosure will be described below with reference to the drawings. Note that the description will be given in the following order.

[0033] <Problems to be Considered in the Present Disclosure>

[0034] <First Embodiment>

[0035] <Second Embodiment>

[0036] <Modification Example>

[0037] Note that the embodiments of the present disclosure to be described below are suitable specific examples of the present disclosure, and the content of the present disclosure is not limited to those embodiments and the like.

[0038] <Problems to be considered in the present disclosure>

[0039] First, the problems to be considered in the present disclosure will be described to facilitate understanding of the present disclosure. As described above, there is a need to improve the conversion efficiency in the field of power supply circuits. Generally, in the range of load ratios smaller than the maximum load, the efficiency of the power supply circuit is poor, and many power supply circuits exhibit the maximum conversion efficiency in the range of load ratios equal to or greater than the medium level of the maximum load. In particular, in a power supply circuit that reduces switching losses by using resonance phenomena, this tendency becomes stronger.

[0040] However, in electronic devices, there are many devices (such as motors, audio devices, and lighting devices) that provide a small actual average power relative to the instantaneous maximum power. The power supply circuit installed on such an electronic device is used for a long time at a small load relative to the maximum load and is used in a state with poor conversion efficiency. To solve this problem, the above-described technique described in Patent Document 1 uses a power supply circuit that stores electrical energy (hereinafter, also simply referred to as energy) when the load current is small and releases energy when the load current increases, thereby performing time shifting of the peak power of the electronic device.

[0041] In this method, since the reduction of the confirmed voltage or the increase of the load current is used to operate the peak power suppression circuit, the power supply voltage changes. Audio devices or lighting devices (such as the backlight of a television device) are devices with repetitive peak loads and small actual loads, but in the case of such electronic devices, the change in the power supply voltage causes fluctuations in the screen or sound quality, so the technique of Patent Document 1 cannot be applied.

[0042] In addition, the technique described in Patent Document 2 has a configuration that suppresses changes in the output voltage, but even within the range where the isolated power supply can be powered independently, losses are caused due to the operation of the peak shift circuit. In addition, since the load ratio of the isolated power supply is always small, the efficiency is reduced, and it is difficult to improve the efficiency in the actual use area. Considering the above description, the details of the present disclosure will be described using embodiments.

[0043] <First Embodiment>

[0044] [Examples of Loads]

[0045] First, specific examples of electronic devices (loads) that can be connected to the power supply circuit of the present disclosure will be described. Figure 1 A and B each show an example of such an electronic device. In Figure 1In A and B, the horizontal axis represents time, and the vertical axis represents the magnitude of the load current. Assume that the electronic device connected to the power supply circuit is a load device that generates an average load continuously obtained over a long period of time and a load device that generates a peak load greater than the continuous load even in a short period of time. As will be described in detail later, the power supply circuit according to the present disclosure needs to be able to continuously supply the required power in the average load region, but does not need to be able to supply the required power when the load is at its peak.

[0046] The load can be obtained continuously or discretely by on / off control of a switch. The time setting of the short-time peak load / long-time average load depends on the electronic device serving as the load.

[0047] Figure 1 A shows the change in the load current of an audio device, which is a specific example of the former case. The load current of the audio device changes continuously as shown in Figure 1 A. Assuming that the load at 20 Hz is the minimum frequency, in the case of the audio device, less than 50 ms is a short time, and more than 50 ms is a long time.

[0048] Figure 1 B shows the change in the load current of the lighting device (specifically, the backlight) of a television device, which is a specific example of the latter case. By switch control, the load current of the lighting device of the television device changes discretely as shown in Figure 1 B. When assuming pulse width modulation (PWM) control with a 60 Hz cycle, less than 17 ms is a short time, and a value greater than 17 ms is a long time.

[0049] The power supply circuit according to the present disclosure can be applied to the above audio device or television device, motor control circuit, and various other electronic devices.

[0050] [Configuration Example of Power Supply Circuit]

[0051] Figure 2 is a diagram for describing a configuration example of a power supply circuit (power supply circuit 1) according to the first embodiment. In power supply circuit 1, an input power supply 2 is connected to the input side, and a load 3 is connected to the output side. The input power supply 2 is, for example, a commercial power supply. The input power supply 2 can be a battery or the like. The load 3 can be the above audio device or lighting device, but can also be other electronic devices.

[0052] The power supply circuit 1 includes, for example, a voltage conversion circuit 11, a bidirectional voltage conversion circuit 12, a first reference voltage source 13, a first error amplifier 14, a second reference voltage source 15, a second error amplifier 16, a first capacitor C1, and a second capacitor C2.

[0053] The voltage conversion circuit 11 appropriately converts the input voltage from the input power supply 2 and outputs the converted voltage via the output lines L1 and L2. The output lines L1 and L2 are connected to the load 3. For example, an LLC resonant converter can be used as the voltage conversion circuit 11.

[0054] The first capacitor C1, which is an example of the first power storage element, smoothes the output of the voltage conversion circuit 11. A power storage element such as an electrolytic capacitor or an electric double layer capacitor can be used as the first capacitor C1.

[0055] The second capacitor C2 is an example of the second power storage element. A power storage element such as an electrolytic capacitor or an electric double layer capacitor can be used as the second capacitor C2.

[0056] The bidirectional voltage conversion circuit 12 is a circuit capable of charging and discharging the second capacitor C2. The second capacitor C2 is connected to the input side of the bidirectional voltage conversion circuit 12. Further, the output side of the bidirectional voltage conversion circuit 12 is connected in parallel with the first capacitor C1.

[0057] The first reference voltage source 13 generates a set voltage (hereinafter, also appropriately referred to as the first voltage value) for the first capacitor C1. The first voltage value in this embodiment is a preset fixed value. The first voltage value is input to one input terminal of the first error amplifier 14. As will be described in detail later, in the power supply circuit 1, the bidirectional voltage conversion circuit 12 operates to control the voltage of the first capacitor C1 to have (maintain) the first voltage value.

[0058] The voltage value of the first capacitor C1 is input to the other input terminal of the first error amplifier 14. The first error amplifier 14 outputs a voltage obtained by amplifying the voltage difference between the two inputs (i.e., the first voltage value and the voltage value of the first capacitor C1). The detection result of the first error amplifier 14 is input to the bidirectional voltage conversion circuit 12.

[0059] The second reference voltage source 15 generates a set voltage (hereinafter, also appropriately referred to as the second voltage value) for the second capacitor C2. The second voltage value in this embodiment is a preset fixed value. Note that the first voltage value and the second voltage value can be the same value or can be different values. The second voltage value is input to one input terminal of the second error amplifier 16. As will be described in detail later, in the power supply circuit 1, the voltage conversion circuit 11 operates to control the voltage of the second capacitor C2 to have (maintain) the second voltage value.

[0060] The voltage value of the second capacitor C2 is input to the other input terminal of the second error amplifier 16. The second error amplifier 16 outputs a voltage obtained by amplifying the voltage difference between the two inputs, that is, the second voltage value and the voltage value of the second capacitor C2. The detection result of the second error amplifier 16 is input to the voltage conversion circuit 11.

[0061] [Operation Example of Power Supply Circuit]

[0062] (First Operation Example)

[0063] Next, an operation example of the power supply circuit 1 will be described. First, reference will be made to Figure 3 describe the first operation example of the power supply circuit 1. The first operation example is an operation example of the power supply circuit 1 when the load current required by the load 3 is equal to or less than the maximum current that the voltage conversion circuit 11 can provide.

[0064] Figure 3 A of shows the time variation of the magnitude of the load current. Figure 3 B of shows the time variation of the magnitude of the output current (supply current) of the voltage conversion circuit 11. Figure 3 C of shows the time variation of the magnitude of the output current of the bidirectional voltage conversion circuit 12.

[0065] As Figure 3 shown in A of, for example, when the load 3 is connected to the power supply circuit 1 at time t1, a load current flows. In Figure 3 the example shown in A of, the load current increases as time elapses (e.g., from time t1 to time t2), and reaches its maximum value near the middle of time t2 and time t3. Then, the load current gradually decreases and reaches zero at time t4. In this example, the increase and decrease of the load current are continuous, but as described above, depending on the load 3, the increase and decrease of the load current can be discrete. In any case, in this example, the load current does not exceed the maximum current MC that the voltage conversion circuit 11 can supply. As Figure 3 shown in B of, the voltage conversion circuit 11 supplies a current corresponding to the increase and decrease of the load current to the load 3.

[0066] The load current flows, which causes the voltage of the first capacitor C1 to drop, and the first error amplifier 14 detects that the voltage of the first capacitor C1 has dropped below the first voltage value. The detection result of the first error amplifier 14 is supplied to the bidirectional voltage conversion circuit 12. The bidirectional voltage conversion circuit 12 that has been supplied with the detection result of the first error amplifier 14 controls the voltage of the first capacitor C1 to have the first voltage value. Specifically, the bidirectional voltage conversion circuit 12 discharges the second capacitor C2 and supplies the discharge current caused by the discharge of the second capacitor C2 to the first capacitor C1. This controls the voltage of the first capacitor C1 to have the first voltage value.

[0067] The second capacitor C2 is discharged, and the voltage of the second capacitor C2 drops. The second error amplifier 16 detects that the voltage of the second capacitor C2 has dropped below the second voltage value. The voltage conversion circuit 11 that has been supplied with the detection result of the second error amplifier 16 controls the voltage of the second capacitor C2 to have the second voltage value. Specifically, the voltage conversion circuit 11 supplies a current to the second capacitor C2 in order to set the voltage of the second capacitor C2 to the second voltage value. This current is supplied to the second capacitor C2 via the first capacitor C1 and the bidirectional voltage conversion circuit 12. Therefore, the supply capacity of the voltage conversion circuit 11 matches the load current of the load 3, and the operation continues in a state where the supply current of the bidirectional voltage conversion circuit 12 as shown in Figure 3 C is zero.

[0068] (Second operating example)

[0069] Next, a second operating example of the power supply circuit 1 will be described with reference to Figure 4 The second operating example is an operating example of the power supply circuit 1 when the load current required by the load 3 is greater than the maximum current that the voltage conversion circuit 11 can provide.

[0070] Figure 4 A in shows the time variation of the magnitude of the load current. Figure 4 B in shows the time variation of the magnitude of the output current of the voltage conversion circuit 11. Figure 4 C in shows the time variation of the magnitude of the output current of the bidirectional voltage conversion circuit 12. Figure 4 D in shows the time variation of the voltage of the second capacitor C2.

[0071] As Figure 4 A in shows, in this example, it is assumed that from time t2 to time t3, the load current of the load 3 becomes greater than the maximum current MC that the voltage conversion circuit 11 can supply.

[0072] After the load 3 is connected to the power supply circuit 1, during the interval in which the load current is equal to or less than the maximum current MC that the voltage conversion circuit 11 can supply (the interval from time t1 to time t2), the voltage conversion circuit 11 outputs a current corresponding to the load current (see Figure 4 the interval from time t1 to time t2 in B of Figure 4 ). At this time, as described above, the output current of the voltage conversion circuit 11 is balanced with the load current, and the current of the bidirectional voltage conversion circuit 12 becomes zero (see the interval from time t1 to time t2 in C of

[0073] Figure 4 ).

[0074] After time t2, that is, even when the load current is equal to or lower than the supply capacity of the power supply, due to the voltage drop of the second capacitor C2, the voltage conversion circuit 11 does not reduce the output current according to the load current and continuously outputs the maximum current MC that can be supplied (see Figure 4 B of

[0075] In the maximum current MC that can be supplied, a current (overcurrent) exceeding the load current is supplied from the voltage conversion circuit 11 to the first capacitor C1. However, through the operation of the bidirectional voltage conversion circuit 12 to maintain the voltage of the first capacitor C1, the overcurrent is stored in the second capacitor C2 (from the perspective of the bidirectional voltage conversion circuit 12, the second capacitor C2 is charged with a negative current). Therefore, the voltage of the second capacitor C2 is restored (see Figure 4 D of

[0076] The voltage conversion circuit 11 outputs the maximum current MC that can be supplied until the voltage of the second capacitor C2 reaches the second voltage value even when the load current reaches zero at time t4. Figure 4At time t5 in D), the voltage conversion circuit 11 stops outputting. Similar to the state from time t1 to time t2, the load current and the output current of the voltage conversion circuit 11 match, and the current of the bidirectional voltage conversion circuit 12 is in a zero state. Here, the discharge energy (the part with vertical hatching) of the bidirectional voltage conversion circuit 12 in the state from time t2 to time t3 and the charge energy (the part with horizontal hatching) of the bidirectional voltage conversion circuit 12 in the state from time t3 to time t5 have equal values.

[0077] [Effects obtained in this embodiment]

[0078] According to this embodiment, the power supply circuit does not need to cope with short-term peak loads and operates at a constantly high load rate, thereby improving the conversion efficiency of the power supply. The improvement in efficiency enables the miniaturization of the power supply circuit and the reduction of costs. In addition, this configuration constantly feeds the voltage to be supplied to the load to the bidirectional voltage conversion circuit, which enables suppressing the change in the output voltage compared with the conventional technology.

[0079] <Second Embodiment>

[0080] Next, the second embodiment will be described. Note that in the description of the second embodiment, configurations or configurations of the same quality that are the same as those in the above description will be denoted by the same reference numerals, and repeated descriptions will be appropriately omitted. In addition, unless otherwise specified, the content described in the first embodiment can be applied to the second embodiment.

[0081] The circuit configuration of the power supply circuit in the second embodiment is the same as that of the first embodiment. In the second embodiment, the switching operation of the voltage conversion circuit 11 is performed in a burst mode (intermittent switching operation).

[0082] Reference will be made to Figure 5 Describe an operation example of the power supply circuit according to the second embodiment. Figure 5 The content shown in A to D of Figure 4 is the same as the content shown in A to D of

[0083] As Figure 5 shown in A of Figure 5As shown in B of FIG. [reference numeral], the voltage conversion circuit 11 outputs a current exceeding the load current, for example, from time t2 to time t3, from time t4 to time t5, and from time t6 to time t7. The current exceeding the load current flowing during these periods is charged in the second capacitor C2. In other words, the current exceeding the load current is output as a negative current from the bidirectional voltage conversion circuit 12 (see Figure 5 C of FIG. [reference numeral]), and the second capacitor C2 is charged (see Figure 5 D of FIG. [reference numeral]).

[0084] In addition, during the period when the voltage conversion circuit 11 stops, such as from time t3 to time t4 or from time t5 to time t6, the bidirectional voltage conversion circuit 12 supplies current to the load (see Figure 5 C of FIG. [reference numeral]). Therefore, the voltage of the first capacitor C1 remains constant.

[0085] In the case where the load current suddenly increases at time t8 (i.e., at the moment when the voltage conversion circuit 11 stops), a response delay of the voltage conversion circuit 11 occurs, and for the load, the supply current of the voltage conversion circuit 11 is insufficient, but the insufficient part is supplied by the bidirectional voltage conversion circuit 12 (see Figure 5 C of FIG. [reference numeral]). The bidirectional voltage conversion circuit 12 continuously keeps the voltage of the first capacitor C1 constant through these operations, so that conventional pulsation or load response delay can be compensated.

[0086] Generally, a technique for improving the power supply efficiency of a load in a light load range by making a voltage conversion circuit perform intermittent operations is known. However, due to problems such as pulsation of the output voltage or load response delay during the intermittent period, when the required accuracy of the output voltage is high, intermittent operations cannot be performed. However, as described above, according to this embodiment, even if a response delay occurs, the current required by the load can be compensated by the supply current from the bidirectional voltage conversion circuit 12, so that the occurrence of the above-mentioned inconveniences can be avoided.

[0087] [Example]

[0088] Next, the present disclosure will be described in detail using examples. Note that the present disclosure is not limited to the following examples.

[0089] (First Example)

[0090] Figure 6 A to D of FIG. [reference numeral] show an example in which a buck converter that steps down the voltage from the second capacitor C2 to the first capacitor C1 is applied as the bidirectional voltage conversion circuit 12. The content shown in Figure 6 A to D of FIG. [reference numeral] is the same as the content shown in Figure 4 A to D of FIG. [reference numeral].

[0091] In the case of using a buck converter, the second voltage value set for the voltage conversion circuit 11 is set to a value greater than the first voltage value. Specifically, assume that the first voltage value is 10 V and the second voltage value is 20 V.

[0092] As Figure 6 shown in A of, assume that the load operates with a duty ratio of 50% in a cycle of 17 ms, and the peak power is 200 W which is 10 V·20 A. The average power becomes 100 W according to the duty ratio of 50%, and the voltage conversion circuit 11 needs to be able to continuously supply 100 W.

[0093] Within the load range up to 100 W that can be supplied by the voltage conversion circuit 11 (for example, the range from time t1 to time t2), the bidirectional voltage conversion circuit 12 continues to operate at 0 A (see Figure 6 C of). At the peak load of 200 W, 100 W (a current of 10 A) is supplied from the voltage conversion circuit 11, and there is a shortage of 100 W for the load (a load current of 20 A). The lacking 100 W of power is supplied from the bidirectional voltage conversion circuit 12 (see Figure 6 C of). Therefore, the power supply to the load continues. At this time, the energy stored in the second capacitor C2 is consumed, and the consumed value in this instance is 850 mJ. To cover the energy of 850 mJ, the capacitance of the second capacitor C2 needs to be more than 5.67 mF.

[0094] The capacitance of the second capacitor C2 can be calculated as follows, for example.

[0095] The energy is calculated as follows:

[0096] Lacking power P × lacking time t = energy E.

[0097] The energy E in this instance is

[0098] E = 100 [W] × 8.5 [ms] = 850 [mJ].

[0099] The energy that can be stored in the capacitor is represented by the following equation (1).

[0100] E = C*V 2 / 2 (1)

[0101] According to equation (1), in the Figure 6 instance shown,

[0102] C2 > 2E / (Vc2 2 −Vc1 2 (where Vc2 represents the second voltage value and Vc1 represents the first voltage value)

[0103] holds, and

[0104] The required capacitance C2 in the second capacitor C2 is

[0105] C2 = 2 * 850 [mJ] / (20 [V] 2 - 10 [V] 2 ) = 5.66·· [mF].

[0106] (Second example)

[0107] Figure 7 is an example when using the buck - boost or boost - type bidirectional voltage conversion circuit 12 under load voltage and load current similar to Figure 6 . Figure 7 A in Figure 7 shows the output current of the bidirectional voltage conversion circuit 12. Figure 7 B in

[0108] shows the time variation of the voltage of the second capacitor C2 when the bidirectional voltage conversion circuit 12 is a buck - boost converter.

[0109] C in

[0110] shows the time variation of the voltage of the second capacitor C2 when the bidirectional voltage conversion circuit 12 is a boost converter. Figure 7 In this example, since the bidirectional voltage conversion circuit 12 has a boost function, there is no limitation on the magnitude relationship between the first voltage value and the second voltage value, and the energy stored in the second capacitor C2 can be used below the voltage of the first capacitor C1.

[0111] C2 > 2E / (Vc2 2 ) = 2 * 850 [mJ] / (20 [V] 2 ) = 4.25 [mF]

[0112] holds. In the example shown in Figure 7 C of

[0113] C2 > 2E / (Vc2 2 ) = 2 * 850 [mJ] / (8 [V] 2 ) = 26.5625 [mF]

[0114] holds.

[0115] <Modification Example>

[0116] The embodiments of the present disclosure have been specifically described above, and the content of the present disclosure is not limited to the above embodiments, and various modifications can be made based on the technical concept of the present disclosure.

[0117] As Figure 8 shown, the first voltage value set for the first reference voltage source 13 may not be a fixed value, but a variable value that can be set to any value. In addition, the second voltage value set for the second reference voltage source 15 may be a variable value. This makes it possible to optimize the first voltage value or the second voltage value according to the load characteristics of various electronic devices. In addition, during the operation of the power supply circuit, the first voltage value or the second voltage value may change dynamically according to the load characteristics. This makes it possible to further improve the conversion efficiency of the power supply circuit. In addition, setting the first voltage value to be variable makes it possible to respond to the control required by the electronic device acting as a load (for example, expecting to increase / decrease the volume, increase / decrease the brightness, and increase / decrease the rotational speed of the motor).

[0118] The present disclosure can be implemented not only as a power supply circuit but also as a control method executed by the power supply circuit or an electronic device using the power supply circuit.

[0119] The configurations, methods, steps, shapes, materials, numerical values, etc. described in the above embodiments are only examples, and different configurations, methods, steps, shapes, materials, numerical values, etc. from the above can be used as needed. The above embodiments and modification examples can be appropriately combined.

[0120] The present disclosure may also have the following configuration.

[0121] (1) A power supply circuit, comprising:

[0122] A voltage conversion circuit that converts an input voltage;

[0123] A first energy storage element that smoothes the output of the voltage conversion circuit;

[0124] A bidirectional voltage conversion circuit whose output side is connected in parallel with the first energy storage element; and

[0125] A second energy storage element connected to the input side of the bidirectional voltage conversion, wherein,

[0126] The voltage conversion circuit controls the voltage of the second energy storage element to have a second voltage value, and

[0127] The bidirectional voltage conversion circuit controls the voltage of the first energy storage element to have a first voltage value.

[0128] (2) The power supply circuit according to (1), wherein,

[0129] When the load current of the load connected to the first energy storage element is greater than the maximum current that the voltage conversion circuit can supply, the voltage conversion circuit continuously outputs the maximum current that it can supply.

[0130] (3) The power supply circuit according to (2), wherein,

[0131] The bidirectional voltage conversion circuit supplies a discharge current to the first energy storage element, and the discharge current is caused by the discharge of the second energy storage element.

[0132] (4) The power supply circuit according to (3), wherein,

[0133] When the load current of the load is lower than the maximum current that the voltage conversion circuit can supply, the voltage conversion circuit continuously outputs the maximum current that it can supply until the voltage of the second energy storage element reaches the second voltage value.

[0134] (5) The power supply circuit according to any one of (1) to (4), wherein,

[0135] The first voltage value is variable.

[0136] (6) The power supply circuit according to any one of (1) to (4), wherein,

[0137] The first voltage value is a predetermined fixed value.

[0138] (7) The power supply circuit according to any one of (1) to (6), wherein,

[0139] The second voltage value is variable.

[0140] (8) The power supply circuit according to any one of (1) to (6), wherein,

[0141] The second voltage value is a predetermined fixed value.

[0142] (9) The power supply circuit according to any one of (1) to (8), wherein,

[0143] The voltage conversion circuit operates with intermittent switching operations.

[0144] (10) A control method, comprising:

[0145] Converting an input voltage through a voltage conversion circuit;

[0146] Smoothing the output of the voltage conversion circuit through a first energy storage element;

[0147] The voltage of the first energy storage element is controlled to have a first voltage value by a bidirectional voltage conversion circuit, the output side of the bidirectional voltage conversion circuit is connected in parallel with the first energy storage element, and the input side of the bidirectional voltage conversion circuit is connected to the second energy storage element; and

[0148] The voltage of the second energy storage element is controlled to have a second voltage value by a voltage conversion circuit.

[0149] (11) An electronic device, comprising:

[0150] A power supply circuit according to any one of (1) to (10).

[0151] List of reference numerals

[0152] 1 Power supply circuit

[0153] 2 Input power supply

[0154] 3 Load

[0155] 11 Voltage conversion circuit

[0156] 12 Bidirectional voltage conversion circuit

[0157] 13 First reference voltage source

[0158] 14 First error amplifier

[0159] 15 Second reference voltage source

[0160] 16 Second error amplifier

[0161] C1 First capacitor

[0162] C2 Second capacitor

[0163] L1, L2 Output lines.

Claims

1. A power supply circuit, comprising: A voltage conversion circuit that converts an input voltage; A first energy storage element that smoothes the output of the voltage conversion circuit; A bidirectional voltage conversion circuit, the output side of which is connected in parallel with the first energy storage element; And A second energy storage element connected to the input side of the bidirectional voltage conversion, wherein The voltage conversion circuit controls the voltage of the second energy storage element to have a second voltage value, and The bidirectional voltage conversion circuit controls the voltage of the first energy storage element to have a first voltage value.

2. The power supply circuit according to claim 1, wherein When the load current of the load connected to the first energy storage element is greater than the maximum current that the voltage conversion circuit can supply, the voltage conversion circuit continuously outputs the maximum current that can be supplied.

3. The power supply circuit according to claim 2, wherein The bidirectional voltage conversion circuit supplies a discharge current to the first energy storage element, and the discharge current is caused by the discharge of the second energy storage element.

4. The power supply circuit according to claim 3, wherein When the load current of the load is lower than the maximum current that the voltage conversion circuit can supply, the voltage conversion circuit continuously outputs the maximum current that can be supplied until the voltage of the second energy storage element reaches the second voltage value.

5. The power supply circuit according to claim 1, wherein The first voltage value is variable.

6. The power supply circuit according to claim 1, wherein The first voltage value is a predetermined fixed value.

7. The power supply circuit according to claim 1, wherein The second voltage value is variable.

8. The power supply circuit according to claim 1, wherein The second voltage value is a predetermined fixed value.

9. The power supply circuit according to claim 1, wherein The voltage conversion circuit operates with an intermittent switching operation.

10. A control method, comprising: Converting an input voltage through a voltage conversion circuit; Smoothing the output of the voltage conversion circuit through a first energy storage element; Controlling the voltage of the first energy storage element to have a first voltage value through a bidirectional voltage conversion circuit, the output side of which is connected in parallel with the first energy storage element, and the input side of which is connected to a second energy storage element; And Controlling the voltage of the second energy storage element to have a second voltage value through the voltage conversion circuit.

11. An electronic device, comprising: The power supply circuit according to claim 1.

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