Voltage regulating circuit and energy storage power supply thereof

Abstract

The utility model discloses a voltage regulating circuit and energy storage power supply thereof. The voltage regulating circuit comprises a voltage drive unit, an amplification and adjustment unit and a current sensing unit. The voltage drive unit generates and outputs a first current variation to the amplification and adjustment unit according to an input voltage variation. The amplification and adjustment unit amplifies the first current variation and generates a second current variation to the current sensing unit. The current sensing unit generates a first voltage variation according to the second current variation, so that the voltage variation output to the voltage reduction linear voltage stabilizing circuit is less than the input voltage variation. When the input voltage increases, the voltage drive unit outputs the current variation to the amplification and adjustment unit for amplification. The current sensing unit generates a corresponding voltage variation according to the amplified current variation, so that the voltage variation output to the voltage reduction linear voltage stabilizing circuit is less than the input voltage variation, and the loss of the voltage reduction linear voltage stabilizing circuit is reduced.

Description

Technical Field

[0001] This utility model relates to the field of electronic technology, and in particular to a voltage regulation circuit and its energy storage power supply. Background Technology

[0002] An LDO (Low Dropout Regulator) power supply circuit is a widely used step-down linear regulator circuit in electronic devices. Its main function is to convert a higher input voltage into a stable lower output voltage, providing a stable power supply for subsequent circuits. LDO power supply circuits have advantages such as simple circuit structure, low cost, low noise, and fast transient response, and are therefore widely used in portable electronic devices, communication equipment, automotive electronics, and other fields.

[0003] However, traditional LDO power supply circuits have a significant technical drawback: when the voltage difference between the input and output voltages is large, the LDO power chip experiences substantial power loss. Specifically, the power loss on the LDO power chip equals the input voltage minus the output voltage multiplied by the output current, i.e., P_loss = (V_in - V_out) × I_out. When the input-output voltage difference increases, this linear loss leads to severe heat generation in the device, affecting not only the circuit's efficiency but also potentially triggering thermal protection or damaging the device, thus impacting the reliability and stability of the entire system.

[0004] Especially in applications with large input voltage fluctuations, the aforementioned shortcomings of traditional LDO power supply circuits become more pronounced. When the input voltage increases, the losses on the LDO power chip increase accordingly, leading to intensified thermal stress; conversely, when the load current increases, the power loss also increases simultaneously, further worsening heat dissipation. These problems make ordinary LDO power supply circuits unsuitable for applications with large input voltage variations or frequent load changes. Utility Model Content

[0005] The main technical problem solved by this utility model embodiment is to provide a voltage regulation circuit and its energy storage power supply, which can solve at least some of the defects of existing LDO power supply circuits.

[0006] In a first aspect, this utility model provides a voltage regulation circuit, comprising: a voltage driving unit, an amplification and regulation unit, and a current sensing unit; the voltage driving unit and the current sensing unit are both connected to an input voltage source, and the amplification and regulation unit is connected to the voltage driving unit, the current sensing unit, and a buck linear regulator circuit; the voltage driving unit is used to generate and output a first current change to the amplification and regulation unit based on the input voltage change; the amplification and regulation unit is used to amplify the first current change to generate a second current change to the current sensing unit; the current sensing unit generates a first voltage change based on the second current change, such that the change in the output voltage of the current sensing unit to the output voltage of the buck linear regulator circuit is less than the input voltage change.

[0007] Optionally, when the voltage driving unit, the current sensing unit, and the amplification and adjustment unit meet the first preset condition, the first voltage change is equal to the input voltage change, so that the output voltage is constant.

[0008] Optionally, both the amplification adjustment unit and the current sensing unit are connected to the buck linear regulator circuit; the current sensing unit also generates a second voltage change based on the load current change of the buck linear regulator circuit, so that the change in the output voltage is less than the change in the input voltage.

[0009] Optionally, the voltage driving unit is further configured to generate a driving voltage to the amplification and adjustment unit based on the input voltage; when the driving voltage is greater than or equal to a preset voltage threshold, the amplification and adjustment unit starts to operate.

[0010] Optionally, the voltage driving unit includes resistors R1 and R2; the first end of resistor R1 is connected to the positive terminal of the input voltage source, the second end of resistor R1 is connected to the first end of resistor R2 and the input terminal of the amplification and adjustment unit, and the second end of resistor R2 is connected to the negative terminal of the input voltage source.

[0011] Optionally, the amplification and adjustment unit includes a transistor Q1, the base of which is connected to the output terminal of the voltage driving unit, the collector of which is connected to the output terminal of the current sensing unit, and the emitter of which is connected to the negative terminal of the input voltage source.

[0012] Optionally, the amplification adjustment unit further includes a resistor R6, which is connected between the collector of the transistor Q1 and the output terminal of the current sensing unit.

[0013] Optionally, the current sensing unit includes a resistor R3, with the first end of the resistor R3 connected to the positive terminal of the input voltage source and the second end of the resistor R3 connected to the output terminal of the amplification and adjustment unit.

[0014] Optionally, the first preset condition is: R3*β / R1=1, where R3 is the resistance value of resistor R3, R1 is the resistance value of resistor R1, and β is the current amplification factor of transistor Q1.

[0015] Secondly, this utility model provides an energy storage power supply, including: a step-down linear regulator circuit; and a voltage regulation circuit as described in the first aspect.

[0016] The beneficial effects of this utility model embodiment are as follows: Unlike the prior art, this utility model embodiment uses a voltage driving unit to amplify the change in output current when the input voltage increases, so that the current sensing unit generates a corresponding voltage change based on the amplified current change, thereby making the voltage change output to the buck linear regulator circuit less than the change in input voltage, thus reducing the loss of the buck linear regulator circuit. Attached Figure Description

[0017] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0018] Figure 1 This is a schematic diagram of a voltage regulation circuit provided by an embodiment of the present invention;

[0019] Figure 2 This is a circuit diagram of a voltage regulation circuit provided by an embodiment of the present invention;

[0020] Figure 3 Based on Figure 2 The simulation waveform diagram of the voltage regulation circuit shown is shown.

[0021] Figure 4 Based on Figure 2 Another simulation waveform of the voltage regulation circuit shown. Detailed Implementation

[0022] To facilitate understanding of this utility model, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element, or one or more intermediate elements may exist between them. When an element is described as being "connected" to another element, it can be directly connected to the other element, or one or more intermediate elements may exist between them. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this specification are for illustrative purposes only.

[0023] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0024] In some embodiments of this application, a schematic diagram of a voltage regulation circuit is provided, referring to... Figure 1 The voltage regulation circuit 10 includes a voltage drive unit 110, an amplification and adjustment unit 120, and a current sensing unit 130. The voltage regulation circuit 10 is connected to the input voltage source 30 and the buck linear regulator circuit 20, and is used to reduce the power loss of the buck linear regulator circuit 20 when the input voltage fluctuates.

[0025] Specifically, both the voltage driving unit 110 and the current sensing unit 130 are connected to the input voltage source 30 to receive the power signal provided by the input voltage source 30. The amplification and regulation unit 120 is connected to the voltage driving unit 110, the current sensing unit 130, and the buck linear regulator circuit 20 to form a complete voltage regulation loop.

[0026] In some embodiments of this application, the voltage driving unit 110 is used to generate and output a first current change to the amplification and adjustment unit 120 based on the input voltage change. Specifically, when the input voltage of the input voltage source 30 changes, the voltage driving unit 110 can sense the change in input voltage and convert the input voltage change into a corresponding first current change. By way of example and not limitation, the working principle of the voltage driving unit 110 is based on the principle of resistor voltage division. The input voltage is divided by an internal resistor network. When the input voltage changes, the voltage at the voltage division point also changes accordingly, thereby generating a corresponding current change output to the subsequent circuit.

[0027] In some embodiments of this application, the amplification and adjustment unit 120 is used to amplify the first current change output by the voltage driving unit 110 to generate a second current change for the current sensing unit 130. Specifically, the amplification and adjustment unit 120 has a current amplification function, which can amplify a small first current change into a larger second current change, thereby enhancing the circuit's regulation capability. As an example and not a limitation, the working principle of the amplification and adjustment unit 120 is based on the current amplification characteristics of a transistor. When the base current changes, the collector current will change accordingly according to a certain amplification factor, thereby achieving effective amplification of the current signal.

[0028] In some embodiments of this application, the current sensing unit 130 generates a first voltage change based on the second current change output by the amplification and adjustment unit 120, so that the change in the output voltage of the current sensing unit 130 to the buck linear regulator circuit 20 is less than the change in the input voltage. The function of the current sensing unit 130 is to convert the current change into a voltage change and to effectively control the input voltage of the buck linear regulator circuit 20 by adjusting the voltage output to the buck linear regulator circuit 20. By way of example and not limitation, the working principle of the current sensing unit 130 is based on Ohm's law; when the current through the sensing resistor changes, the voltage across the sensing resistor also changes accordingly, thereby producing a corresponding voltage regulation effect.

[0029] In some embodiments of this application, when the voltage driving unit 110, the current sensing unit 130, and the amplification and adjustment unit 120 meet the first preset condition, the first voltage change is equal to the input voltage change, so that the output voltage remains constant. Specifically, by reasonably designing the parameter configuration of each unit, the ideal state of keeping the output voltage constant when the input voltage fluctuates can be achieved. When the first preset condition is met, the circuit can achieve complete voltage compensation, that is, the change in input voltage is completely canceled, so that the input voltage of the buck linear regulator circuit 20 remains stable.

[0030] In some embodiments of this application, both the amplification adjustment unit 120 and the current sensing unit 130 are connected to the buck linear regulator circuit 20, forming a dual regulation mechanism. The current sensing unit 130 also generates a second voltage change based on the change in load current of the buck linear regulator circuit 20, so that the change in output voltage is less than the change in input voltage. When the load current of the buck linear regulator circuit 20 changes, the current sensing unit 130 can sense the change in load current and generate corresponding voltage regulation, further optimizing the regulation performance of the circuit.

[0031] In some embodiments of this application, the voltage driving unit 110 is further configured to generate a driving voltage to the amplification and adjustment unit 120 based on the input voltage. It is easy to understand that the driving voltage is generated to ensure that the amplification and adjustment unit 120 can start operating under suitable conditions. Specifically, the amplification and adjustment unit 120 starts operating when the driving voltage is greater than or equal to a preset voltage threshold. As an example and not a limitation, the preset voltage threshold can be set to 0.7V. When the driving voltage reaches or exceeds this threshold, the transistor in the amplification and adjustment unit 120 starts to conduct and operates normally, thereby achieving the current amplification function.

[0032] In some embodiments of this application, the first preset condition is a specific mathematical relation used to determine the matching relationship between the parameters of each component. As an example and not a limitation, the first preset condition is: R3* β / R1=1, where R3 is the resistance of resistor R3, R1 is the resistance of resistor R1, and β is the current amplification factor of transistor Q1. When the circuit parameters satisfy the above mathematical relationship, the optimal operating state of constant output voltage can be achieved when the input voltage fluctuates.

[0033] In some embodiments of this application, the voltage regulation circuit 10 operates as follows: when the input voltage of the input voltage source 30 changes, the voltage driving unit 110 senses the change in input voltage and generates a first current change; the amplification and adjustment unit 120 receives the first current change and amplifies it into a second current change; the current sensing unit 130 generates a first voltage change based on the second current change and adjusts the voltage output to the buck linear regulator circuit 20. Through the above adjustment process, the change in the input voltage of the buck linear regulator circuit 20 is effectively controlled, making it less than the change in the input voltage of the input voltage source 30, thereby significantly reducing the power loss of the buck linear regulator circuit 20.

[0034] It is easy to understand that when the load current changes, the current sensing unit 130 can also generate a second voltage change, further optimizing the circuit's regulation performance. Specifically, when the load current increases, the voltage on the current sensing unit 130 will increase accordingly, thereby reducing the voltage value at the input of the buck linear regulator circuit 20 and optimizing power loss when the load current changes.

[0035] In some embodiments of this application, a circuit schematic of a voltage regulation circuit is provided, referring to... Figure 2As an example and not a limitation, the voltage drive unit 110 includes resistors R1 and R2, forming a resistive voltage divider network. Specifically, the first terminal of resistor R1 is connected to the positive terminal of the input voltage source VCC, the second terminal of resistor R1 is connected to the first terminal of resistor R2 and the input terminal of the amplification and adjustment unit 120, and the second terminal of resistor R2 is connected to the negative terminal of the input voltage source VCC. The voltage divider circuit formed by resistors R1 and R2 can divide the input voltage of the input voltage source VCC according to a certain ratio, and the voltage at the dividing point is output as the drive voltage to the amplification and adjustment unit 120. When the input voltage changes, the voltage at the dividing point will also change accordingly according to the resistance ratio, thereby realizing the effective transmission of the input voltage change. The working principle of the resistive voltage divider network is based on Kirchhoff's voltage law. The distribution ratio of the input voltage on resistors R1 and R2 depends on the ratio of the resistance values ​​of the two resistors, and the voltage at the dividing point is equal to the input voltage multiplied by the ratio of resistor R2 to the sum of resistors R1 and R2.

[0036] In some embodiments of this application, the amplification and adjustment unit 120 includes a transistor Q1 to effectively amplify the current signal. Specifically, the base of transistor Q1 is connected to the output terminal of the voltage driving unit 110, the collector of transistor Q1 is connected to the output terminal of the current sensing unit 130, and the emitter of transistor Q1 is connected to the negative terminal of the input voltage source VCC. By way of example and not limitation, transistor Q1 is configured as an NPN transistor. When the base voltage exceeds the emitter voltage by approximately 0.7V, transistor Q1 begins to conduct. The operating principle of transistor Q1 is based on the current amplification characteristics of a bipolar junction transistor (BJT). When a small control current is injected into the base, the collector will generate an amplified current several times or even hundreds of times greater. The amplification factor is determined by the β parameter of the transistor. When the driving voltage output by the voltage driving unit 110 causes the voltage between the base and emitter of transistor Q1 to reach the conduction threshold, a small change in the base current will cause a significant change in the collector current, thereby effectively amplifying the first current change to the second current change.

[0037] By way of example and not limitation, the amplification and adjustment unit 120 also includes a resistor R6, which is connected between the collector of transistor Q1 and the output of the current sensing unit 130. The function of resistor R6 is to reduce power loss in transistor Q1 and improve the overall efficiency of the circuit. Specifically, when a large current flows through the circuit, resistor R6 can share part of the voltage drop, reducing the voltage between the collector and emitter of transistor Q1, thereby reducing the power consumption and heat generation of transistor Q1. The working principle of resistor R6 is based on the power distribution principle. By connecting a resistor in series in the collector circuit of transistor Q1, a portion of the voltage drop that would originally be entirely borne by the transistor can be distributed to resistor R6, achieving optimized power loss distribution.

[0038] In some embodiments of this application, the current sensing unit 130 includes a resistor R3 to achieve effective current-to-voltage conversion. Specifically, the first terminal of resistor R3 is connected to the positive terminal of the input voltage source VCC, and the second terminal of resistor R3 is connected to the output terminal of the amplification and regulation unit 120. Resistor R3 acts as a current sensing resistor, generating a corresponding voltage drop across it when current flows through it. The working principle of resistor R3 is based on Ohm's law, that is, the voltage across the resistor is equal to the current flowing through the resistor multiplied by the resistance value. When the second current change output by the amplification and regulation unit 120 flows through resistor R3, a corresponding voltage change is generated across resistor R3, which directly affects the voltage value output to the buck linear regulator circuit 20.

[0039] When the voltage (Ube) of the PN junction between the base and emitter of transistor Q1 is below 0.7V, transistor Q1 does not work. When the PN junction between the base and emitter of transistor Q1 is conducting, Ube = 0.7V. Therefore, the voltage regulation circuit requires an input voltage V2 that satisfies V2*R2 / (R1+R2)≥0.7V to be effective. In some embodiments of this application, the specific working process of the voltage regulation circuit is as follows: Assuming the amplification factor of the transistor is β, when the input voltage V2 satisfies V2*R2 / (R1+R2)≥0.7V, the base current of the transistor is:

[0040] Ib = (V2-0.7) / R1-0.7 / R2(1)

[0041] According to (1), it can be deduced that when the input voltage V2 of the input voltage source VCC increases by ΔV, the voltage divider network formed by resistors R1 and R2 causes the base voltage of transistor Q1 to increase accordingly, and the increased base current of transistor Q1 is:

[0042] ΔIb=ΔV / R1(2)

[0043] Due to the current amplification effect of transistor Q1, the increase in collector current is:

[0044] ΔIc=ΔIb*β(3)

[0045] According to the superposition theorem of currents, the increased collector current flowing through resistor R3 produces an additional voltage drop across resistor R3 as follows:

[0046] ΔUR3=ΔIc*R3(4)

[0047] This voltage drop causes the voltage at the connection point between resistor R3 and the positive terminal of the input voltage source VCC to increase, while the voltage at the connection point between resistor R3 and the buck linear regulator circuit 20 decreases relatively.

[0048] Substituting formula (4) into formula (2), we can obtain:

[0049] ΔUR3 = R3*β*ΔV / R1 (5)

[0050] It is not difficult to understand that when the first preset condition R3 is met... β When 1 / R1=1, the voltage drop across resistor R3 is exactly equal to the increase in input voltage, ensuring that the output voltage to the buck linear regulator circuit 20 remains constant. Even if the first preset condition cannot be fully met, as long as R3... β Even with 1 / R1 close to 1, the circuit can still significantly reduce the fluctuation range of the output voltage, thereby effectively reducing the power loss of the buck linear regulator circuit 20.

[0051] Specifically, when the load current of the buck linear regulator circuit 20 increases, the current through resistor R3 also increases accordingly, leading to a larger voltage drop across resistor R3 and further reducing the input voltage to the buck linear regulator circuit 20. The voltage regulation caused by the load current change provides a second layer of protection for the circuit, effectively controlling the power loss of the buck linear regulator circuit 20 even under sudden load changes.

[0052] Figure 3 and Figure 4 These are simulation waveforms of the voltage regulation circuit, where V2 is the input voltage and V3 is the output voltage. Figure 3 It can be seen that when R3 β When 1 / R1=1, the output voltage remains constant when the input voltage fluctuates. However, R3... β 1 / R1=1 is a rather special case and is difficult to achieve in reality. Even so, from Figure 4 It can also be seen that the voltage regulation circuit has significantly less fluctuation in output voltage than in input voltage, thereby reducing losses on the LDO power chip.

[0053] Unlike existing technologies, this embodiment of the invention uses a voltage driving unit to amplify the change in output current when the input voltage increases. This amplifies the change in current and enables the current sensing unit to generate a corresponding change in voltage based on the amplified change in current. This ensures that the change in voltage output to the buck linear regulator circuit is less than the change in input voltage, thereby reducing the losses in the buck linear regulator circuit.

[0054] In some embodiments of this application, an energy storage power supply is also provided, which includes a buck linear regulator circuit 20 and a voltage regulation circuit 10 as described in any of the above embodiments. Specifically, the voltage regulation circuit 10 is located before the buck linear regulator circuit 20, receives power input from the input voltage source 30, and outputs the regulated voltage to the input terminal of the buck linear regulator circuit 20. By way of example and not limitation, when the energy storage power supply is working, the input voltage source 30 can be a battery pack, a charger, or other power supply device. The voltage regulation circuit 10 preprocesses the input voltage, and the buck linear regulator circuit 20 further regulates the preprocessed voltage to the voltage level required by the load.

[0055] It should be noted that while the preferred embodiments of this utility model are provided in the specification and accompanying drawings, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are not intended to impose additional limitations on the content of this utility model; their purpose is to provide a more thorough and comprehensive understanding of the disclosure of this utility model. Furthermore, the above-described technical features can be combined with each other to form various embodiments not listed above, all of which are considered to be within the scope of this utility model specification. Moreover, those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A voltage regulation circuit, characterized in that, include: Voltage drive unit, amplification and adjustment unit, and current sensing unit; The voltage driving unit and the current sensing unit are both connected to the input voltage source, and the amplification and adjustment unit is connected to the voltage driving unit, the current sensing unit, and the buck linear regulator circuit. The voltage driving unit is used to generate and output a first current change to the amplification and adjustment unit based on the input voltage change. The amplification and adjustment unit is used to amplify the first current change and generate a second current change to the current sensing unit. The current sensing unit generates a first voltage change based on the second current change, so that the change in the output voltage of the current sensing unit to the output voltage of the buck linear regulator circuit is less than the input voltage change.

2. The circuit according to claim 1, characterized in that, When the voltage driving unit, the current sensing unit, and the amplification and adjustment unit meet the first preset condition, the first voltage change is equal to the input voltage change, so that the output voltage is constant.

3. The circuit according to claim 1, characterized in that, Both the amplification adjustment unit and the current sensing unit are connected to the buck linear regulator circuit. The current sensing unit also generates a second voltage change based on the load current change of the buck linear regulator circuit, so that the change in the output voltage is less than the change in the input voltage.

4. The circuit according to claim 1, characterized in that, The voltage driving unit is also used to generate a driving voltage to the amplification and adjustment unit according to the input voltage; when the driving voltage is greater than or equal to a preset voltage threshold, the amplification and adjustment unit starts to work.

5. The circuit according to claim 2, characterized in that, The voltage driving unit includes resistor R1 and resistor R2; The first end of resistor R1 is connected to the positive terminal of the input voltage source, the second end of resistor R1 is connected to the first end of resistor R2 and the input terminal of the amplification and adjustment unit, and the second end of resistor R2 is connected to the negative terminal of the input voltage source.

6. The circuit according to claim 2, characterized in that, The amplification and adjustment unit includes a transistor Q1. The base of the transistor Q1 is connected to the output terminal of the voltage driving unit, the collector of the transistor Q1 is connected to the output terminal of the current sensing unit, and the emitter of the transistor Q1 is connected to the negative terminal of the input voltage source.

7. The circuit according to claim 6, characterized in that, The amplification and adjustment unit also includes a resistor R6, which is connected between the collector of the transistor Q1 and the output terminal of the current sensing unit.

8. The circuit according to claim 2, characterized in that, The current sensing unit includes a resistor R3, the first end of which is connected to the positive terminal of the input voltage source, and the second end of which is connected to the output terminal of the amplification and adjustment unit.

9. The circuit according to claim 2, characterized in that, The first preset condition is: R3*β / R1=1, Where R3 is the resistance value of resistor R3, R1 is the resistance value of resistor R1, and β is the current amplification factor of transistor Q1.

10. An energy storage power source, characterized in that, include: Buck linear regulator circuit; as well as The voltage regulation circuit as described in any one of claims 1-9.

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