Voltage conversion circuit, chip, and electronic device

Abstract

The invention relates to the technical field of power management chips, in particular to a voltage conversion circuit, a chip and electronic equipment. The voltage conversion circuit comprises an energy storage circuit, a discharging circuit, a first voltage sampling circuit, a second voltage sampling circuit and a control circuit. The energy storage circuit receives the charging voltage signal to carry out charging energy storage; the output end of the discharging circuit is used for outputting a discharging voltage signal; the first voltage sampling circuit is used for sampling a first voltage value on the energy storage circuit; the second voltage sampling circuit is used for calculating a reference voltage value according to the charging voltage signal and the discharging voltage signal; and the control circuit is used for turning off the energy storage circuit when determining that the first voltage value reaches the reference voltage value, and turning on the discharging circuit for discharging. According to the voltage conversion circuit, the reference voltage value can be dynamically adjusted, and when the first voltage value on the energy storage circuit reaches the reference voltage value, the charging process is ended and the discharging circuit is opened to discharge outwards, so that the working efficiency of the voltage conversion circuit is improved.

Description

Technical Field

[0001] The present application relates to the technical field of power management chips, and in particular to a voltage conversion circuit, a chip, and an electronic device. Background Art

[0002] As a common functional circuit, voltage conversion circuit is often used in various electronic devices. It can boost or buck the input voltage and then output a stable supply voltage at the load end.

[0003] In the related art, the voltage conversion circuit mainly includes an energy storage circuit and a discharge circuit. The energy storage circuit is charged by an external power supply to complete energy storage. After the energy storage is completed, the discharge circuit is opened to discharge to the outside. By controlling the working time of the energy storage circuit and the discharge circuit, the volt-second balance in the circuit is achieved. Among them, in a working cycle, in the related art, during the charging process of the energy storage circuit, the charging current value on the energy storage circuit will gradually increase, so the voltage drop on the sampling resistor caused by the charging current value in the energy storage circuit will also gradually increase. When the voltage drop on the sampling resistor reaches the target voltage value, the energy storage circuit is stopped from being charged, and then the discharge is opened for discharge. In this way, in each working cycle, the voltage value of the sampling resistor on the energy storage circuit needs to reach the target voltage value. When the load changes, the discharge voltage actually output by the discharge circuit will also change. The voltage value on the energy storage circuit in each cycle needs to reach the target voltage value, which will reduce the overall working efficiency of the voltage conversion circuit and fail to meet the response requirements of the load in time. Summary of the invention

[0004] The present application provides a voltage conversion circuit, a chip and an electronic device to solve the technical problem of reduced working efficiency of the voltage conversion circuit in the related art, and realizes that the target voltage value when the energy storage circuit is charged can be dynamically adjusted according to the change of the load, so as to achieve the purpose of improving the working efficiency of the circuit.

[0005] In a first aspect, the present application provides a voltage conversion circuit, which includes: a storage circuit, a discharge circuit, a first voltage sampling circuit, a second voltage sampling circuit, and a control circuit;

[0006] The input end of the energy storage circuit is used to receive a charging voltage signal; the energy storage circuit includes an energy storage device, and the charging voltage signal is used to charge the energy storage device so that the energy storage device stores energy;

[0007] The output end of the energy storage circuit is connected to the input end of the discharge circuit, and the output end of the discharge circuit is used to output a discharge voltage signal;

[0008] The first voltage sampling circuit is used to sample the first voltage value on the energy storage circuit; the second voltage sampling circuit is used to sample the charging voltage signal and the discharging voltage signal, and calculate the reference voltage value according to the charging voltage signal and the discharging voltage signal;

[0009] The control circuit is used to determine whether the first voltage value reaches the reference voltage value, and if so, output a discharge control signal; the discharge control signal is used to turn off the energy storage circuit and turn on the discharge circuit for discharge.

[0010] In a possible embodiment, the control circuit is also used to determine whether the first voltage value is reduced to zero, and if so, output a charging control signal; the charging control signal is used to turn off the discharge circuit and turn on the energy storage circuit for charging and energy storage.

[0011] In a possible embodiment, the energy storage circuit further includes a first resistor and a first transistor;

[0012] The first end of the energy storage device is the input end of the energy storage circuit, and is used to receive the charging voltage signal. The second end of the energy storage device is connected to the first end of the first resistor, the second end of the first resistor is connected to the first electrode of the first transistor, the second electrode of the first transistor is grounded, and the second end of the first transistor is grounded.

[0013] The control electrode of the first transistor is used to receive the charging control signal or the discharging control signal; the charging control signal is used to control turning on the first transistor; and the discharging control signal is used to control turning off the first transistor.

[0014] In a possible embodiment, the second voltage sampling circuit includes a first voltage sampling terminal, a second voltage sampling terminal, an analog calculator, and a second resistor;

[0015] The first voltage sampling terminal is connected to the energy storage circuit and is used to sample the charging voltage signal on the energy storage circuit; the second voltage sampling terminal is connected to the discharge circuit and is used to collect the discharge voltage signal of the discharge circuit;

[0016] The analog calculator is used to generate a first current signal according to a preset operating frequency, an inductance value of the energy storage device, the charging voltage signal and the discharging voltage signal; the output end of the analog calculator is used to output the first current signal;

[0017] The output end of the analog calculator is connected to the first end of the second resistor, the second end of the second resistor is grounded, and the first end of the second resistor is the output end of the second voltage sampling circuit, for outputting the reference voltage value;

[0018] The first resistor and the second resistor have the same resistance value.

[0019] In a possible embodiment, generating the first current signal according to a preset operating frequency, an inductance value of the energy storage device, the charging voltage signal, and the discharging voltage signal includes:

[0020] The current value of the first current signal is calculated according to the following formula:

[0021]

[0022] Wherein, Ts is the operating frequency of the circuit, L is the inductance value of the energy storage device, Vout is the voltage value of the charging voltage signal, and Vin is the voltage value of the discharging voltage signal.

[0023] In a possible embodiment, the discharge circuit includes a second transistor;

[0024] The first electrode of the second transistor is the input end of the discharge circuit; the first electrode of the second transistor is connected to the second end of the first resistor, and the second electrode of the second transistor is the output end of the discharge circuit; the control electrode of the second transistor is used to receive the charging control signal or the discharging control signal; the charging control signal is used to control the closing of the second transistor; the discharging control signal is used to control the opening of the second transistor.

[0025] In a possible embodiment, the first voltage sampling circuit includes a sampling amplifier;

[0026] The non-inverting input terminal of the sampling amplifier is connected to the first end of the first resistor, the inverting input terminal of the sampling amplifier is connected to the second end of the first resistor, and the output terminal of the sampling amplifier is used to output the first voltage value.

[0027] In a possible embodiment, the control circuit includes a comparator; the non-inverting input terminal of the comparator is connected to the output terminal of the sampling amplifier, and is used to receive the first voltage value output by the sampling amplifier; the inverting input terminal of the comparator is connected to the output terminal of the second voltage sampling circuit, and is used to receive the reference voltage value output by the second voltage sampling circuit; the output terminal of the comparator is used to output a comparison signal, and the logic state of the comparison signal is used to characterize the comparison result between the first voltage value and the reference voltage value.

[0028] In a second aspect, the present application also provides a chip, which includes a voltage conversion circuit as described in any one of the above items.

[0029] In a third aspect, the present application also provides an electronic device, which includes the chip as described above; or includes the voltage conversion circuit as described in any one of the above items.

[0030] According to the voltage conversion circuit provided by the present application, it includes: an energy storage circuit, a discharge circuit, a first voltage sampling circuit, a second voltage sampling circuit and a control circuit. Among them, the energy storage circuit receives a charging voltage signal to charge and store energy; the output end of the energy storage circuit is connected to the input end of the discharge circuit, and the output end of the discharge circuit is used to output a discharge voltage signal; the first voltage sampling circuit is used to sample the first voltage value on the energy storage circuit; the second voltage sampling circuit is used to sample the charging voltage signal and the discharge voltage signal, and calculate the reference voltage value according to the charging voltage signal and the discharge voltage signal; the control circuit is used to determine whether the first voltage value reaches the reference voltage value, and if so, output a discharge control signal; the discharge control signal is used to turn off the energy storage circuit and open the discharge circuit for discharge. It can be seen that the present application can dynamically adjust the reference voltage value according to the charging voltage signal and the discharge voltage signal, and when the first voltage value on the energy storage circuit reaches the reference voltage value, the charging process is ended and the discharge circuit is opened to discharge to the outside, thereby improving the working efficiency of the voltage conversion circuit.

[0031] The beneficial effects provided in the above-mentioned second aspect and various possible designs of the above-mentioned second aspect can refer to the beneficial effects brought about by the above-mentioned first aspect and various possible implementation methods of the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other embodiments can also be obtained based on these drawings.

[0033] Figure 1 A schematic diagram of the structure of a voltage conversion circuit provided in an embodiment of the present application;

[0034] Figure 2 A schematic diagram of the structure of a second voltage sampling circuit provided in an embodiment of the present application;

[0035] Figure 3 One of the waveform diagrams of the first voltage value, the reference voltage value and the comparison signal provided in the embodiment of the present application;

[0036] Figure 4 The second waveform diagram of the first voltage value, the reference voltage value and the comparison signal provided in the embodiment of the present application. DETAILED DESCRIPTION

[0037] In this application, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c alone can represent: a, b, c, a and b, a and c, or a, b, and c, where a, b, and c can be single or multiple. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0038] The directions or positional relationships indicated by terms such as "center", "longitudinal", "lateral", "up", "down", "left", "right", "front", and "back" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.

[0039] The terms "connected" and "connected" should be understood in a broad sense. For example, the "connected" or "connected" of a circuit structure can refer to not only physical connection, but also electrical connection or signal connection. For example, it can be directly connected, that is, physically connected, or indirectly connected through at least one intermediate element, as long as the circuit is connected, or it can be the internal connection of two elements; signal connection can refer to signal connection through a circuit or through a media medium, such as radio waves. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0040] The transistor in the present application is a three-terminal transistor, and its three terminals are a control electrode, a first electrode, and a second electrode. The transistor can be a bipolar transistor or a field effect transistor, etc. For example, when the transistor is a bipolar transistor, its control electrode refers to the base of the bipolar transistor, the first electrode can be the collector or emitter of the bipolar transistor, and the corresponding second electrode can be the emitter or collector of the bipolar transistor; when the transistor is a field effect transistor, its control electrode refers to the gate of the field effect transistor, the first electrode can be the drain or source of the field effect transistor, and the corresponding second electrode can be the source or drain of the field effect transistor.

[0041] In energy storage systems, power conversion is a key process that involves the storage and release of energy, as well as converting the stored energy back into a form that can be used by the grid when needed. Energy storage bidirectional DC / DC power converter (BDC for short) is one of the core components in this process. This converter can not only realize the bidirectional flow of energy, that is, effective energy exchange between energy storage devices and the grid, between energy storage devices, or between energy storage devices and loads, but also maintain stable performance output under various complex working conditions, such as voltage fluctuations, current shocks, etc.

[0042] Among them, the basic principle of the energy storage bidirectional DC / DC power converter is based on power electronics technology, which realizes the rise and fall of DC voltage and the regulation of current by controlling the on and off of the switching device. Compared with the traditional unidirectional DC / DC converter, the energy storage bidirectional DC / DC power converter adds the function of reverse energy transmission, so that the charging and discharging management of the energy storage device can be realized. Specifically, by adjusting the duty cycle of the switching device (that is, the ratio of the on time of the switching device to the cycle time), the output voltage and current are controlled. In the charging mode, the converter converts the high-voltage DC power of the power grid into a low-voltage DC power suitable for charging the energy storage device; in the discharging mode, the low-voltage DC power of the energy storage device is converted into the high-voltage DC power required by the load. This flexible energy conversion method makes the energy storage bidirectional DC / DC power converter have a wide range of application prospects in energy storage systems.

[0043] In addition, the battery energy storage power conversion system (PCS) is a device that is matched with the energy storage battery pack and is connected between the battery pack and the power grid. The core of its work is to convert the AC power grid into DC form and store it in the electrochemical battery pack, or to convert the battery pack energy into AC form and feed it back to the power grid. There are many specific technical solutions for PCS. The energy storage power conversion system of mainstream manufacturers generally adopts a three-phase voltage type two-level or three-level PWM rectifier, which has the advantages of flexible and controllable dynamic characteristics, bidirectional power flow, sinusoidal output current with low harmonic content, and flexible adjustment of the power factor between -1 and 1. The performance of these systems has a key impact on the service life of the entire electrochemical battery energy storage unit, and is of great significance to improving the safety and economy of battery energy storage power stations.

[0044] Among them, the voltage conversion circuit is an important circuit part in the power conversion system. The working efficiency and stability of the voltage conversion circuit determine the working efficiency and stability of the power conversion system, thereby determining the working stability of the electronic equipment.

[0045] In the related art, the voltage conversion circuit will pre-set a fixed reference voltage value according to the load size. During the charging process of the energy storage circuit, the current value of the inductor in the energy storage circuit will gradually increase, which will cause the voltage drop on the sampling resistor in the energy storage circuit to increase. When the voltage drop on the sampling resistor in the energy storage circuit increases to the reference voltage value, the energy storage circuit is turned off to stop the charging process, and the discharge circuit is opened to discharge the load, so as to achieve boost or buck processing, thereby achieving power conversion. However, during the power conversion process, when the load changes, the corresponding charging voltage value and discharge voltage value will also change. Then, since the preset reference voltage value is a fixed value, in each cycle, the first voltage value on the energy storage circuit needs to reach a fixed reference voltage value before the energy storage circuit is turned off to end the charging process, and then the discharge circuit is opened to discharge to the outside. This will reduce the overall working efficiency of the voltage conversion circuit and fail to meet the response requirements of different loads in a timely manner.

[0046] In order to overcome the defects in the above-mentioned related technologies, the present application provides a voltage conversion circuit, which includes: an energy storage circuit, a discharge circuit, a first voltage sampling circuit, a second voltage sampling circuit and a control circuit. Among them, the energy storage circuit is used to receive a charging voltage signal for charging and energy storage; the output end of the energy storage circuit is connected to the input end of the discharge circuit, and the output end of the discharge circuit is used to output a discharge voltage signal, thereby realizing power conversion. Among them, the first voltage sampling circuit is used to sample the first voltage value on the energy storage circuit; the second voltage sampling circuit is used to sample the charging voltage signal and the discharging voltage signal, and calculate the reference voltage value according to the charging voltage signal and the discharging voltage signal, so that when the load changes, the voltage values ​​of the charging voltage signal and the discharging voltage signal will also change accordingly, and the corresponding reference voltage value can be calculated according to the charging voltage signal and the discharging voltage signal, and the control circuit can turn off the energy storage circuit to end charging when the first voltage value reaches the reference voltage value, and open the discharge circuit to discharge to the outside. In this way, the reference voltage value can be dynamically adjusted, thereby improving the working efficiency of the voltage conversion circuit.

[0047] Figure 1 For a schematic diagram of the structure of the voltage conversion circuit provided in the embodiment of the present application, see Figure 1 As shown, the voltage conversion circuit includes: an energy storage circuit 10, a discharge circuit 20, a first voltage sampling circuit 30, a second voltage sampling circuit and a control circuit 40.

[0048] The input end of the energy storage circuit 10 is used to receive the charging voltage signal Vin; the energy storage circuit 10 includes an energy storage device, and the charging voltage signal VIN is used to charge the energy storage device, so as to charge the energy storage device, so that the energy storage circuit 10 completes energy storage. The output end of the energy storage circuit 10 is connected to the input end of the discharge circuit 20, and the output end of the discharge circuit 20 is used to output the discharge voltage signal Vout, and the discharge voltage signal Vout can power the load.

[0049] The first voltage sampling circuit 30 is used to sample the first voltage value V1 on the energy storage circuit; the second voltage sampling circuit is used to sample the charging voltage signal Vin and the discharging voltage signal Vout, and calculate the reference voltage value Vref according to the charging voltage signal Vin and the discharging voltage signal Vout.

[0050] The control circuit 40 is used to determine whether the first voltage value V1 reaches the reference voltage value Vref, and if so, output a discharge control signal; the discharge control signal is used to turn off the energy storage circuit 10 and turn on the discharge circuit 20 for external discharge.

[0051] It can be understood that, in this embodiment, the energy storage circuit 10 and the discharge circuit 20 work periodically. In one cycle, the discharge circuit 20 is first turned off, and the energy storage circuit 10 is turned on. The energy storage circuit 10 receives the input charging voltage signal Vin to charge the energy storage device so that the energy storage device completes energy storage. Then the energy storage circuit 10 is turned off, and the discharge circuit 20 is turned on, so that the energy storage device and the discharge circuit 20 form a discharge loop to supply power to the external load. In other words, the energy storage circuit 10 and the discharge circuit 20 are alternately turned on to achieve the purpose of power conversion.

[0052] The discharge circuit 20 outputs a discharge voltage signal Vout to supply power to the external load. In the current cycle, when the size of the external load changes, the charging voltage signal Vin and the discharge voltage signal Vout will also change. In this way, if the energy storage circuit 10 is charged in the next cycle, the preset fixed reference voltage value is still used as a reference, the charging time of the energy storage circuit 10 will be too short or too long, thereby affecting the working efficiency of the voltage conversion circuit.

[0053] It can be seen that a second voltage sampling circuit is designed in the voltage conversion circuit of the present application, and the reference voltage value Vref can be dynamically calculated according to the charging voltage signal Vin and the discharging voltage signal Vout through the second voltage sampling circuit, and then the charging process of the energy storage circuit 10 is controlled based on the reference voltage value Vref. Compared with the related art in which the reference voltage value Vref is set to a fixed value, the voltage conversion circuit of the present application can dynamically adjust the peak value of the charging voltage according to the change of the load, thereby improving the working efficiency of the voltage conversion circuit.

[0054] Correspondingly, in the second half of a working cycle, the control circuit is also used to determine whether the first voltage value is reduced to zero. If so, a charging control signal is output; the charging control signal is used to turn off the discharge circuit 20 and turn on the energy storage circuit 10 for charging and energy storage.

[0055] It can be understood that within a working cycle, when it is detected whether the first voltage value on the sampling resistor in the energy storage circuit 10 is reduced to zero, it can be determined that the inductor current in the energy storage circuit 10 is reduced to zero, that is, it can be determined that the discharge is completed, and a charging control signal can be output to control the discharge circuit 20 to turn off and end the charging process, and at the same time control the energy storage circuit 10 to turn on to start the charging process.

[0056] In some embodiments, see Figure 1 As shown, the energy storage circuit 10 of this embodiment further includes a first resistor R1 and a first transistor Q1; the first end of the energy storage is the input end of the energy storage circuit 10, which is used to receive the charging voltage signal Vin, the second end of the energy storage is connected to the first end of the first resistor R1, the second end of the first resistor R1 is connected to the first electrode of the first transistor Q1, the second electrode of the first transistor Q1 is grounded, and the second end of the first transistor Q1 is grounded GND. The control electrode of the first transistor Q1 is used to receive a charging control signal or a discharging control signal; the charging control signal is used to control the opening of the first transistor Q1 so that the energy storage circuit 10 forms a charging loop; the discharging control signal is used to control the closing of the first transistor Q1 to disconnect the charging loop.

[0057] In some embodiments, see Figure 1 As shown, the energy storage device in the energy storage circuit 10 of this embodiment is a first inductor L1, and the first inductor L1 can store energy during the charging process. The first end of the first inductor L1 is the input end of the energy storage circuit 10, which is used to receive the charging voltage signal Vin, and the second end of the first inductor L1 is connected to the first end of the first resistor R1. During the charging process, the current value on the first inductor L1 gradually increases from zero. During the discharging process, the first inductor L1 and the discharge circuit 20 form a discharge loop, and the current value on the first inductor L1 gradually decreases to zero.

[0058] Please continue to see Figure 1 As shown, the discharge circuit 20 provided in this embodiment includes a second transistor Q2; the first pole of the second transistor Q2 is the input end of the discharge circuit 20; the first pole of the second transistor Q2 is connected to the second end of the first resistor R1, and the second pole of the second transistor Q2 is the output end of the discharge circuit, that is, the second pole of the second transistor Q2 is used to output the discharge voltage signal Vout. The control pole of the second transistor Q2 is used to receive a charging control signal or a discharging control signal; the charging control signal is used to control the closing of the second transistor Q2 so that the discharging circuit is disconnected; the discharging control signal is used to control the opening of the second transistor Q2 so that the second transistor Q2 and the first inductor L1 form a discharging circuit to supply power to the load. It can be seen that during the discharging process, the second end of the first resistor R1 is the output end of the energy storage circuit 10, which is used to output the electric energy stored in the first inductor L1.

[0059] It is understandable that, in the process of the current on the first inductor L1 increasing or decreasing, the current value flowing through the first inductor L1 can be collected to determine whether the current value reaches the preset peak current. However, in the circuit field, the current value collection usually has a certain error, that is, it is difficult to accurately collect the current value on the first inductor L1. Therefore, when the resistance of the sampling resistor in the circuit is constant, the voltage difference across the sampling resistor can be collected to characterize the magnitude of the current value flowing through the first inductor L1 in the circuit. For details, please continue to refer to Figure 1 As shown, the first resistor R1 is connected in series with the first inductor L1. When the current on the first inductor L1 increases or decreases, the current on the first inductor L1 can be determined by collecting the voltage difference on the first resistor R1.

[0060] In some embodiments, see Figure 1 As shown, the first voltage sampling circuit 30 includes a sampling amplifier U1; the non-inverting input terminal of the sampling amplifier U1 is connected to the first end of the first resistor R1, the inverting input terminal of the sampling amplifier U1 is connected to the second end of the first resistor R1, and the output terminal of the sampling amplifier U1 is used to output the first voltage value V1.

[0061] It can be understood that the non-inverting input terminal and the inverting input terminal of the sampling amplifier U1 can collect the voltage difference between the upper and lower ends of the first resistor R1. When the resistance value of the first resistor R1 is fixed, the current value flowing through the first resistor R1 and the first inductor L1 can be represented by the voltage difference between the upper and lower ends of the first resistor R1. In addition, when there are no other resistors or equivalent resistors in the circuit, the voltage difference between the upper and lower ends of the first resistor R1 can represent the first voltage value V1 on the energy storage circuit 10.

[0062] Figure 2For a schematic diagram of the structure of the second voltage sampling circuit provided in the embodiment of the present application, see Figure 2 As shown, the second voltage sampling circuit provided in this embodiment includes a first voltage sampling terminal S1, a second voltage sampling terminal S2, an analog calculator 501 and a second resistor R2.

[0063] The first voltage sampling terminal S1 is connected to the energy storage circuit 10 to sample the charging voltage signal Vin on the energy storage circuit 10; the second voltage sampling terminal S2 is connected to the discharge circuit 20 to collect the discharge voltage signal Vout of the discharge circuit 20. For example, in this embodiment, the first voltage sampling terminal S1 can be specifically connected to the input terminal of the energy storage circuit 10 to collect the charging voltage signal Vin at the input terminal of the energy storage circuit 10, and the second voltage sampling terminal S2 can be specifically connected to the output terminal of the discharge circuit 20 to collect the discharge voltage signal Vout at the output terminal of the discharge circuit 20.

[0064] The second voltage sampling circuit 50 may include two specific voltage sampling modules, the input terminals of which are respectively connected to the first voltage sampling terminal S1 and the second voltage sampling terminal S2, so that the two voltage sampling modules can respectively collect the charging voltage signal Vin and the discharging voltage signal Vout. The voltage sampling module may be specifically understood as a voltage sampling circuit.

[0065] The analog calculator 501 is used to generate a first current signal I1 according to a preset operating frequency Ts, an inductance value L of the energy storage device, a charging voltage signal Vin, and a discharging voltage signal Vout; the output end of the analog calculator 501 is used to output the first current signal I1. The output end of the analog calculator 501 is connected to a first end of a second resistor R2, a second end of the second resistor R2 is grounded, and the first end of the second resistor R2 is an output end S3 of the second voltage sampling circuit 50, and the output end S3 of the second voltage sampling circuit 50 is used to output a reference voltage value Vref.

[0066] In this embodiment, in order to facilitate the calculation of the reference voltage value Vref, the resistance values ​​of the first resistor R1 and the second resistor R2 may be set to be the same.

[0067] In this embodiment, since the operating frequency Ts, the inductance L of the energy storage device, the charging voltage signal Vin, and the discharging voltage signal Vout are all analog signals, an analog calculator 501 is provided to facilitate the operation of these analog signals. The analog calculator 501 can quickly and accurately complete the calculation of the above multiple analog signals to obtain the first current signal I1.

[0068] In this embodiment, the analog calculator 501 generates the first current signal I1 according to the preset operating frequency Ts, the inductance value L of the energy storage device, the charging voltage signal Vin and the discharging voltage signal Vout, specifically including:

[0069] The analog calculator 501 calculates the current value of the first current signal I1 according to the following formula:

[0070]

[0071] In the above formula (1), Ts is the operating frequency of the voltage conversion circuit of this embodiment, and L is the inductance value of the energy storage device in the energy storage circuit 10, which is specifically Figure 1 The inductor of the first inductor L1, Vout is the voltage value of the charging voltage signal, and Vin is the voltage value of the discharging voltage signal.

[0072] It should be noted that, for the voltage conversion circuit provided in this embodiment, its operating frequency Ts is a constant, and the inductance value L of the energy storage device will not change. However, as the load changes, the charging voltage signal Vin and the discharging voltage signal Vout will change. Therefore, the charging voltage signal Vin and the discharging voltage signal Vout collected in this embodiment are both within the current cycle, so as to calculate the reference voltage value Vref of the next cycle, so as to ensure the working efficiency of the voltage conversion circuit in each cycle.

[0073] Please continue to see Figure 2 As shown, the first current signal I1 outputted from the output end of the analog calculator 501 is grounded after passing through the second resistor R2, that is, the first current signal I1 forms a current loop after passing through the second resistor R2. The output end S3 of the second voltage sampling circuit 50 is connected to the upper end of the second resistor R2 to collect the voltage value on the second resistor R2, and the resistance values ​​of the first resistor R1 and the second resistor R2 are the same, and the voltage value collected on the output end S3 is used as the reference voltage value Vref of the next cycle.

[0074] Please continue to see Figure 2As shown, the control circuit 40 of this embodiment includes a comparator U2. The non-inverting input terminal of the comparator U2 is connected to the output terminal of the sampling amplifier U1, and is used to receive the first voltage value V1 output by the sampling amplifier U1; the inverting input terminal of the comparator U2 is connected to the output terminal S3 of the second voltage sampling circuit 50, and is used to receive the reference voltage value Vref output by the second voltage sampling circuit 50; the output terminal of the comparator U2 is used to output a comparison signal PEAK_FLAG, and the logic state of the comparison signal PEAK_FLAG is used to represent the comparison result between the first voltage value V1 and the reference voltage value Vref. In other words, the logic state of the comparison signal PEAK_FLAG can be understood as an identification signal of a comparison result. When the logic state of the output comparison signal PEAK_FLAG is a set state, it represents that the first voltage value V1 reaches the reference voltage value Vref. For example, when the first voltage value V1 reaches the reference voltage value Vref, the logic state of the output comparison signal PEAK_FLAG is a high level, that is, a high level flag signal is output to indicate that the first voltage value V1 reaches the reference voltage value Vref; when the first voltage value V1 does not reach the reference voltage value Vref, the output comparison signal PEAK_FLAG is in a low level state.

[0075] It can be understood that after obtaining the operation logic shown in the above formula (1) provided in this embodiment, it is easy for those skilled in the art to implement the above operation process based on the analog calculator 501 to obtain the reference voltage value Vref.

[0076] Figure 3 One of the waveform diagrams of the first voltage value, the reference voltage value and the comparison signal provided in the embodiment of the present application, see Figure 3 As shown, in some embodiments, when the load at the output end of the voltage conversion circuit becomes smaller, the discharge voltage signal Vout output by the discharge circuit 20 will also decrease accordingly, and the reference voltage value Vref output by the second voltage sampling circuit 50 provided according to this embodiment will also decrease.

[0077] See also Figure 3As shown, at time t1, the comparator U2 detects that the first voltage value V1 reaches the reference voltage value Vref, and the logic state of the comparison signal PEAK_FLAG jumps from a low level to a high level, which is equivalent to outputting a high-level flag signal, and sending the comparison signal PEAK_FLAG to the control circuit 40. At this time, after the control circuit 40 detects the high-level flag signal of the comparison signal PEAK_FLAG, it outputs a discharge control signal, and the discharge control signal includes a first control sub-signal and a second control sub-signal. The first control sub-signal is used to control the closing of the first transistor Q1 to disconnect the charging circuit; the second control sub-signal is used to control the opening of the second transistor Q2, so that the discharge circuit 20 forms a discharge circuit to power the load.

[0078] See also Figure 3 As shown, when the load at the output end of the voltage conversion circuit becomes smaller, the reference voltage value Vref output by the second voltage sampling circuit 50 will also decrease. For example, from time t1 to time t2, the load at the output end of the voltage conversion circuit becomes smaller, and correspondingly, the reference voltage value Vref output by the second voltage sampling circuit 50 also decreases. At time t1, when the comparator U2 detects that the first voltage value V1 is equal to the reference voltage value Vref, the charging process of the first inductor L1 is stopped, and the first transistor Q1 is turned off, and the second transistor Q2 is turned on to discharge to the outside. At time t2, since the reference voltage value Vref decreases, when the comparator U2 detects that the first voltage value V1 is equal to the new reference voltage value Vref, the charging process of the first inductor L1 is stopped, and the first transistor Q1 is turned off, and the second transistor Q2 is turned on to discharge to the outside. It can also be seen from this that in the voltage conversion circuit provided by this embodiment, the reference voltage value Vref gradually changes with the load at the output end. Compared with the related art in which the reference voltage value Vref is set to a fixed value, the voltage conversion circuit of this embodiment can dynamically adjust the reference voltage value Vref according to the load, so that the reference voltage value Vref is always at the most ideal value, which is equivalent to making the inductor current on the first inductor L1 always process the most ideal peak current to improve the power efficiency of the circuit, and at the same time make the voltage conversion circuit have smaller ripple during operation, thereby ensuring the stability of the voltage conversion circuit.

[0079] Figure 4 For the second waveform diagram of the first voltage value, the reference voltage value and the comparison signal provided in the embodiment of the present application, please refer to Figure 4 As shown, in some embodiments, when the load at the output end of the voltage conversion circuit increases, the discharge voltage signal Vout output by the discharge circuit 20 will also decrease accordingly, and the reference voltage value Vref output by the second voltage sampling circuit 50 provided according to this embodiment will also increase.

[0080] See also Figure 4 As shown, at time t3, the comparator U2 detects that the first voltage value V1 reaches the reference voltage value Vref, and the logic state of the comparison signal PEAK_FLAG jumps from a low level to a high level, which is equivalent to outputting a high-level flag signal, and sending the comparison signal PEAK_FLAG to the control circuit 40. At this time, after the control circuit 40 detects the high-level flag signal of the comparison signal PEAK_FLAG, it outputs a discharge control signal, and the discharge control signal includes a first control sub-signal and a second control sub-signal. The first control sub-signal is used to control the closing of the first transistor Q1 to disconnect the charging circuit; the second control sub-signal is used to control the opening of the second transistor Q2, so that the discharge circuit 20 forms a discharge circuit to power the load.

[0081] See also Figure 4 As shown, when the load at the output end of the voltage conversion circuit increases, the reference voltage value Vref output by the second voltage sampling circuit 50 will also increase. For example, from time t3 to time t4, the load at the output end of the voltage conversion circuit increases, and correspondingly, the reference voltage value Vref output by the second voltage sampling circuit 50 also increases. At time t3, when the comparator U2 detects that the first voltage value V1 is equal to the reference voltage value Vref, the charging process of the first inductor L1 is stopped, and the first transistor Q1 is turned off, and the second transistor Q2 is turned on to discharge to the outside. At time t4, since the reference voltage value Vref increases compared to time t3, when the comparator U2 detects that the first voltage value V1 is equal to the new reference voltage value Vref, the charging process of the first inductor L1 is stopped, and the first transistor Q1 is turned off, and the second transistor Q2 is turned on to discharge to the outside. It can also be seen from this that in the voltage conversion circuit provided by this embodiment, the reference voltage value Vref gradually changes with the load at the output end. Compared with the related art in which the reference voltage value Vref is set to a fixed value, the voltage conversion circuit of this embodiment can dynamically adjust the reference voltage value Vref according to the load, so that the reference voltage value Vref is always at the most ideal value, which is equivalent to making the inductor current on the first inductor L1 always process the most ideal peak current to improve the power efficiency of the circuit, and at the same time make the voltage conversion circuit have smaller ripple during operation, thereby ensuring the stability of the voltage conversion circuit.

[0082] In some embodiments, the control circuit 40 can sample the first voltage value V1 on the first inductor L1 through the first voltage sampling circuit 30. When the first voltage value V1 on the first inductor L1 decreases to zero, it is determined that the discharge is completed, and the control circuit 40 outputs a charging control signal, which includes a third control sub-signal and a fourth control sub-signal. The third control sub-signal is used to control the shutdown of the second transistor Q2 to disconnect the discharge loop, and the fourth control sub-signal is used to control the opening of the first transistor Q1 to form a charging loop to recharge the first inductor L1 for energy storage.

[0083] In one embodiment, the control circuit 40 may further include a current sampling circuit, wherein the input end of the current sampling circuit is connected to the first inductor L1 for collecting the current value on the first inductor L1. When the current sampling circuit detects that the current value on the first inductor L1 drops to zero, it is determined that the discharge is completed, and the control circuit 40 outputs a charging control signal, wherein the charging control signal includes a third control sub-signal and a fourth control sub-signal. The third control sub-signal is used to control the turning off of the second transistor Q2 to disconnect the discharge loop, and the fourth control sub-signal is used to control the turning on of the first transistor Q1 to form a charging loop and recharge the first inductor L1 for energy storage.

[0084] In one embodiment, the control circuit 40 further includes a clock circuit, which is used to output a clock signal. It can be seen from the above description that for the voltage conversion circuit of this embodiment, its working cycle T is a fixed time period. In a working cycle, when the time of a working cycle ends, the second transistor Q2 is turned on and off to disconnect the discharge circuit, and the fourth control sub-signal is used to control the opening of the first transistor Q1 to form a charging circuit and recharge the first inductor L1 for energy storage. For example, the clock circuit records the start time of each cycle. After the set cycle length has passed, it is determined that the charging and discharging work in the current cycle is completed, and the voltage conversion circuit is controlled to start the next working cycle.

[0085] Based on the voltage conversion circuit provided in the above embodiment, this embodiment further provides a chip, which includes the voltage conversion circuit as described above.

[0086] It can be understood that the various functional module circuits in the above-mentioned voltage conversion circuit can be integrated into a functional chip to achieve the purpose of power conversion; for example, the above-mentioned energy storage circuit 10, discharge circuit 20, first voltage sampling circuit 30, second voltage sampling circuit 50 and control circuit 40 are integrated into a chip to facilitate direct use in the circuit.

[0087] On the basis of the above embodiment, this embodiment further provides an electronic device, which includes the chip described above; or the electronic device includes the voltage conversion circuit described above.

[0088] It can be understood that a power supply circuit is generally required in an electronic device, and the voltage conversion circuit provided in the embodiment of the present application can be applied to the power supply circuit to ensure the working efficiency and working stability of the power supply circuit and ensure the working life of the electronic device.

[0089] Finally, it should be noted that the above embodiments are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto, and any changes or substitutions within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A voltage conversion circuit, characterized in that: include: An energy storage circuit, a discharge circuit, a first voltage sampling circuit, a second voltage sampling circuit and a control circuit; The input end of the energy storage circuit is used to receive a charging voltage signal; The energy storage circuit includes an energy storage device, and the charging voltage signal is used to charge the energy storage device so that the energy storage device stores energy; The output end of the energy storage circuit is connected to the input end of the discharge circuit, and the output end of the discharge circuit is used to output a discharge voltage signal; The first voltage sampling circuit is used to sample a first voltage value on the energy storage circuit; The second voltage sampling circuit is used to sample the charging voltage signal and the discharging voltage signal, and calculate a reference voltage value according to the charging voltage signal and the discharging voltage signal; The control circuit is used to determine whether the first voltage value reaches the reference voltage value, and if so, output a discharge control signal; The discharge control signal is used to turn off the energy storage circuit and open the discharge circuit for discharge.

2. The voltage conversion circuit according to claim 1, characterized in that: The control circuit is also used to determine whether the first voltage value is reduced to zero, and if so, output a charging control signal; the charging control signal is used to turn off the discharge circuit and turn on the energy storage circuit for charging and energy storage.

3. The voltage conversion circuit according to claim 2, characterized in that: The energy storage circuit also includes a first resistor and a first transistor; The first end of the energy storage device is the input end of the energy storage circuit, and is used to receive the charging voltage signal. The second end of the energy storage device is connected to the first end of the first resistor, the second end of the first resistor is connected to the first electrode of the first transistor, the second electrode of the first transistor is grounded, and the second end of the first transistor is grounded. The control electrode of the first transistor is used to receive the charging control signal or the discharging control signal; The charging control signal is used to control turning on the first transistor; The discharge control signal is used to control turning off the first transistor.

4. The voltage conversion circuit according to claim 3, characterized in that: The second voltage sampling circuit includes a first voltage sampling terminal, a second voltage sampling terminal, an analog calculator and a second resistor; The first voltage sampling terminal is connected to the energy storage circuit and is used to sample the charging voltage signal on the energy storage circuit; the second voltage sampling terminal is connected to the discharge circuit and is used to collect the discharge voltage signal of the discharge circuit; The analog calculator is used to generate a first current signal according to a preset operating frequency, an inductance value of the energy storage device, the charging voltage signal and the discharging voltage signal; the output end of the analog calculator is used to output the first current signal; The output end of the analog calculator is connected to the first end of the second resistor, the second end of the second resistor is grounded, and the first end of the second resistor is the output end of the second voltage sampling circuit, for outputting the reference voltage value; The first resistor and the second resistor have the same resistance value.

5. The voltage conversion circuit according to claim 4, characterized in that: The generating of the first current signal according to the preset operating frequency, the inductance value of the energy storage device, the charging voltage signal and the discharging voltage signal comprises: The current value of the first current signal is calculated according to the following formula: Wherein, Ts is the operating frequency of the circuit, L is the inductance value of the energy storage device, Vout is the voltage value of the charging voltage signal, and Vin is the voltage value of the discharging voltage signal.

6. The voltage conversion circuit according to any one of claims 3 to 5, characterized in that: The discharge circuit includes a second transistor; The first electrode of the second transistor is the input end of the discharge circuit; the first electrode of the second transistor is connected to the second end of the first resistor, and the second electrode of the second transistor is the output end of the discharge circuit; the control electrode of the second transistor is used to receive the charging control signal or the discharging control signal; The charging control signal is used to control turning off the second transistor; and the discharging control signal is used to control turning on the second transistor.

7. The voltage conversion circuit according to any one of claims 3 to 5, characterized in that: The first voltage sampling circuit includes a sampling amplifier; The non-inverting input terminal of the sampling amplifier is connected to the first end of the first resistor, the inverting input terminal of the sampling amplifier is connected to the second end of the first resistor, and the output terminal of the sampling amplifier is used to output the first voltage value.

8. The voltage conversion circuit according to claim 7, characterized in that: The control circuit includes a comparator; the non-inverting input terminal of the comparator is connected to the output terminal of the sampling amplifier, and is used to receive the first voltage value output by the sampling amplifier; the inverting input terminal of the comparator is connected to the output terminal of the second voltage sampling circuit, and is used to receive the reference voltage value output by the second voltage sampling circuit; the output terminal of the comparator is used to output a comparison signal, and the logic state of the comparison signal is used to characterize the comparison result between the first voltage value and the reference voltage value.

9. A chip, characterized in that: Comprising the voltage conversion circuit as described in any one of claims 1-8.

10. An electronic device, characterized in that: Includes the chip as claimed in claim 9; or includes the voltage conversion circuit as claimed in any one of claims 1-8.

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