Adjustable output voltage control circuit and chip

Abstract

This application relates to the field of voltage regulation technology, and provides an adjustable output voltage control circuit and chip. The adjustable output voltage control circuit includes an output feedback module, a voltage regulation module, and an operational amplifier module. The voltage regulation module is electrically connected to both the output feedback module and the operational amplifier module. The output feedback module is used to acquire the output voltage and generate a first node voltage. The operational amplifier module is used to receive the feedback voltage and a reference voltage, and output an adjustment signal. The voltage regulation module is used to receive the injected voltage and adjust the first node voltage based on the injected voltage and the feedback voltage to regulate the output voltage. This application introduces an external injected voltage through the voltage regulation module to change the potential balance of the feedback branch, allowing dynamic adjustment of the output voltage without replacing the voltage divider resistor. The voltage can be flexibly switched during equipment operation without modifying the circuit board, effectively shortening the debugging and product modification cycle, and meeting the multi-level, flexible, and dynamic voltage adjustment requirements of electronic equipment.

Description

Technical Field

[0001] This application belongs to the field of voltage regulation technology, and in particular relates to an adjustable output voltage control circuit and chip. Background Technology

[0002] Existing voltage regulation circuits rely on a fixed internal reference voltage within the chip, combined with output voltage divider resistors, to achieve voltage regulation. The output voltage is determined solely by the resistance ratio of these divider resistors. When adjusting the output voltage, only different resistance values ​​of the divider resistors can be replaced. For electronic devices with multi-level power supply requirements, this solution cannot dynamically adjust the voltage during operation. Switching the output voltage necessitates modifying the circuit board and replacing the divider resistors, resulting in inefficient debugging and product modification processes. This approach fails to meet the current demands of electronic devices for flexible voltage adjustment and dynamic multi-level output. Summary of the Invention

[0003] This application provides an adjustable output voltage control circuit and chip, which can solve the problems of existing voltage regulator circuits that can only adjust the output voltage by replacing the voltage divider resistor, cannot dynamically adjust the voltage, and have low efficiency in modification and debugging.

[0004] In a first aspect, embodiments of this application provide an adjustable output voltage control circuit, including an output feedback module, a voltage regulation module, and an operational amplifier module, wherein the voltage regulation module is electrically connected to the output feedback module and the operational amplifier module respectively; The output feedback module is used to acquire the output voltage and generate the first node voltage. The operational amplifier module is used to receive the feedback voltage and the reference voltage and output the adjustment signal. The voltage regulation module is used to receive the injected voltage and adjust the first node voltage based on the injected voltage and the feedback voltage to adjust the output voltage.

[0005] In one possible implementation of the first aspect, the output voltage is negatively correlated with the injection voltage in a linear relationship.

[0006] In one possible implementation of the first aspect, the output feedback module includes a first resistor and a second resistor, a first terminal of the first resistor is used to receive the output voltage, a second terminal of the first resistor is electrically connected to the first terminal of the second resistor and the voltage regulation module, and a second terminal of the second resistor is grounded.

[0007] In one possible implementation of the first aspect, the voltage regulation module includes a third resistor and a fourth resistor, a first terminal of the third resistor is electrically connected to the output feedback module, a second terminal of the third resistor is electrically connected to the first terminal of the fourth resistor and the operational amplifier module, and the second terminal of the fourth resistor is used to receive the injected voltage. The ratio of the difference between the injected voltage and the reference voltage to the resistance of the fourth resistor is equal to the ratio of the difference between the reference voltage and the first node voltage to the resistance of the third resistor.

[0008] In one possible implementation of the first aspect, the operational amplifier module includes a first operational amplifier, a first input terminal of the first operational amplifier being electrically connected to the voltage regulation module, a second input terminal of the first operational amplifier being used to receive the reference voltage, and an output terminal of the first operational amplifier being used to output the regulation signal.

[0009] In one possible implementation of the first aspect, the adjustable output voltage control circuit further includes a unidirectional conduction module electrically connected to the voltage regulation module to prevent reverse voltage from being transmitted to the voltage regulation module.

[0010] In one possible implementation of the first aspect, the unidirectional conduction module includes a first diode, the anode of which is used to receive the injected voltage, and the cathode of which is electrically connected to the voltage regulation module.

[0011] In one possible implementation of the first aspect, the adjustable output voltage control circuit further includes a voltage soft-start module, which is electrically connected to the voltage regulation module and is used to adjust the soft-start time of the second node voltage, wherein the second node voltage is the voltage of the common terminal of the voltage soft-start module and the voltage regulation module.

[0012] In one possible implementation of the first aspect, the voltage soft-start module includes a fifth resistor and a first capacitor, the first end of the fifth resistor is electrically connected to the first end of the first capacitor and the voltage regulation module, the second end of the fifth resistor is used to receive the injected voltage, and the second end of the first capacitor is grounded.

[0013] Secondly, embodiments of this application provide a chip including the adjustable output voltage control circuit described in any one of the first aspects, wherein the chip leads out at least one voltage regulation control pin; the voltage regulation control pin is used to connect an injected voltage.

[0014] The beneficial effects of the embodiments in this application compared with the prior art are: This application provides an adjustable output voltage control circuit, including an output feedback module, a voltage regulation module, and an operational amplifier module. The output feedback module acquires the output voltage and generates a first node voltage. The operational amplifier module receives the feedback voltage and a reference voltage and outputs an adjustment signal. The voltage regulation module receives an injected voltage and adjusts the first node voltage based on the injected voltage and the feedback voltage, ultimately achieving adjustable output voltage. It is evident that existing technologies can only change the output voltage by replacing the voltage divider resistor, failing to provide online dynamic voltage regulation. This is problematic in multi-voltage scenarios with numerous material types and low efficiency in board modification and debugging. In contrast, this application introduces an external injected voltage through the voltage regulation module to change the potential balance of the feedback branch, dynamically adjusting the output voltage without replacing the voltage divider resistor. This allows for flexible voltage switching during equipment operation, eliminating the need for board modifications and effectively shortening debugging and product modification cycles. It meets the multi-level, flexible, and dynamic voltage regulation requirements of electronic equipment.

[0015] It is understandable that the beneficial effects of the second aspect mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 It is an existing voltage regulation control circuit solution; Figure 2 This is a schematic block diagram of an adjustable output voltage control circuit provided in one embodiment of this application; Figure 3 This is a circuit connection diagram of an adjustable output voltage control circuit provided in an embodiment of this application; Figure 4 This is a circuit connection diagram of an adjustable output voltage control circuit provided in another embodiment of this application; Figure 5 This is a linear relationship diagram between the output voltage and the injection voltage provided in one embodiment of this application; Figure 6 This is a schematic diagram of the external pins of a chip provided in an embodiment of this application; Figure 7 This is a schematic diagram of the internal control of a chip provided in an embodiment of this application.

[0018] In the diagram: 101, Output feedback module; 102, Voltage regulation module; 103, Operational amplifier module; 104, Unidirectional conduction module; 105, Voltage soft-start module. Detailed Implementation

[0019] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0020] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0021] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0022] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if [the described condition or event] is detected" may be interpreted, depending on the context, as "once determined," "in response to determination," "once [the described condition or event] is detected," or "in response to detection of [the described condition or event]."

[0023] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0024] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0025] like Figure 1As shown, the existing voltage regulator control circuit relies on a fixed internal reference voltage VREF and output voltage divider resistors (R1 and R2) to achieve voltage regulation. The output voltage VOUT is determined solely by the ratio of the voltage divider resistor values, satisfying the relationship: VOUT = VREF * (R1 + R2) / R2. When it is necessary to adjust the output voltage VOUT, only voltage divider resistors with different values ​​can be replaced. For electronic devices with multi-level power supply requirements, this solution cannot dynamically adjust the voltage during device operation; if the output voltage needs to be switched, the circuit board must be modified and the voltage divider resistors replaced, resulting in low efficiency in debugging and product modification, and making it difficult to meet the current needs of electronic devices for flexible voltage adjustment and multi-level dynamic output.

[0026] To address the aforementioned issues, this application provides an adjustable output voltage control circuit, including an output feedback module, a voltage regulation module, and an operational amplifier module. The output feedback module acquires the output voltage and generates a first node voltage. The operational amplifier module receives the feedback voltage and a reference voltage and outputs an adjustment signal. The voltage regulation module receives an injected voltage and adjusts the first node voltage based on the injected voltage and the feedback voltage, ultimately achieving adjustable output voltage. It is evident that existing technologies can only change the output voltage by replacing the voltage divider resistor, failing to provide online dynamic voltage regulation. This is problematic in multi-voltage scenarios with numerous material types and low efficiency in board modification and debugging. In contrast, this application introduces an external injected voltage through the voltage regulation module to change the potential balance of the feedback branch, dynamically adjusting the output voltage without replacing the voltage divider resistor. This allows for flexible voltage switching during equipment operation, eliminating the need for board modifications and effectively shortening debugging and product modification cycles. It meets the multi-level, flexible, and dynamic voltage regulation requirements of electronic equipment.

[0027] To illustrate the technical solution described in this application, specific embodiments are provided below.

[0028] Figure 2 A schematic block diagram of an adjustable output voltage control circuit according to an embodiment of this application is shown. See also Figure 2 As shown, the adjustable output voltage control circuit includes an output feedback module 101, a voltage regulation module 102, and an operational amplifier module 103. The voltage regulation module 102 is electrically connected to the output feedback module 101 and the operational amplifier module 103, respectively.

[0029] Specifically, the output feedback module 101 acquires the output voltage VOUT and generates the first node voltage VFBO. The operational amplifier module 103 receives the feedback voltage VFB and the reference voltage VREF and outputs an adjustment signal. The voltage regulation module 102 receives the injected voltage VADJ and adjusts the first node voltage VFBO based on the injected voltage VADJ and the feedback voltage VFB, ultimately achieving adjustable output voltage VOUT. It is evident that existing technologies can only change the output voltage VOUT by replacing the voltage divider resistor, failing to provide online dynamic voltage regulation. This is problematic in scenarios with multiple voltage levels, numerous material types, and low efficiency in board modification and debugging. In contrast, this application introduces an external injected voltage VADJ through the voltage regulation module 102 to change the potential balance of the feedback branch, allowing dynamic adjustment of the output voltage VOUT without replacing the voltage divider resistor. This enables flexible voltage switching during equipment operation, eliminating the need for board modification, effectively shortening the debugging and product modification cycle, and meeting the multi-level, flexible dynamic voltage regulation requirements of electronic equipment.

[0030] It should be noted that the operational amplifier module 103 operates in the negative feedback linear operating region, possessing two main characteristics: virtual short and virtual open. Virtual open means almost no current flows into the operational amplifier module 103 at the feedback node; virtual short ensures that the feedback voltage VFB equals the reference voltage VREF in steady state. When the value of the externally injected voltage VADJ is changed, the current balance between the components inside the voltage regulation module 102 is disrupted, and the potential of the first node shifts accordingly. After detecting the potential difference between the feedback voltage VFB and the reference voltage VREF, the operational amplifier module 103 outputs an adjustment signal to control the power circuit to adjust the output voltage VOUT until the feedback voltage VFB is equal to the reference voltage VREF again, and the circuit reaches a new stable voltage state. Relying on this potential shift adjustment mechanism, the output voltage VOUT can be indirectly adjusted simply by changing the injected voltage VADJ, without needing to modify the voltage divider resistor of the output feedback module 101.

[0031] It should be noted that the operational amplifier module 103 continuously compares the feedback voltage VFB with the internal reference voltage VREF. When the injected voltage VADJ changes, causing a potential shift in the first node and creating a voltage difference between the feedback voltage VFB and the reference voltage VREF, the operational amplifier module 103 outputs a corresponding adjustment signal. If the feedback voltage VFB is lower than the reference voltage VREF, the adjustment signal drives the power circuit to raise the output voltage VOUT; if the feedback voltage VFB is higher than the reference voltage VREF, the adjustment signal controls the power circuit to lower the output voltage VOUT until the feedback voltage VFB is equal to the reference voltage VREF again, and the loop reaches voltage balance again. By adjusting the power circuit's operating state in real time, the dynamic adjustment of the output voltage VOUT is finally achieved. The power circuit is the power path in the voltage regulator circuit that realizes energy conversion and generates the output voltage VOUT. It includes components such as power transistors and capacitors, which are existing technologies and will not be described in detail here.

[0032] It should be noted that the injected voltage VADJ can be provided by various signal sources such as external DAC circuits and reference voltage divider circuits, without the need for high-power driving capability.

[0033] It should be noted that traditional voltage regulation by modifying the voltage divider resistor is an offline static voltage regulation method. Power must be disconnected and hardware components modified to complete the voltage switching, making it impossible to adjust the supply voltage while the device is operating normally. This application, however, is a dynamic online voltage regulation method. After the device is powered on and running stably, the output voltage VOUT can be changed in real time simply by continuously adjusting the value of the injected voltage VADJ, without requiring power disconnection. This is suitable for scenarios where power supply parameters need to be dynamically changed during device operation.

[0034] The following is combined with Figure 3 and Figure 4 The working principle of the adjustable output voltage control circuit is explained in detail.

[0035] In one embodiment of this application, such as Figure 3 As shown, the output feedback module 101 includes a first resistor R1 and a second resistor R2. The first end of the first resistor R1 is used to receive the output voltage VOUT. The second end of the first resistor R1 is electrically connected to the first end of the second resistor R2 and the voltage regulation module 102, respectively. The second end of the second resistor R2 is grounded.

[0036] Specifically, the first resistor R1 and the second resistor R2 form a voltage divider network to collect and divide the output voltage VOUT. A first node voltage VFBO is formed at the connection point of the first resistor R1 and the second resistor R2, converting the high-amplitude output voltage VOUT into a voltage signal suitable for the receiving range of the voltage regulation module 102. This provides a sampling basis for subsequent potential adjustment, thereby achieving real-time sampling feedback of the output voltage VOUT. The first node voltage VFBO and the output voltage VOUT satisfy the formula: VFBO = VOUT * R2 / (R1 + R2). According to the formula, when the first node voltage VFBO is adjusted, the output voltage VOUT will be adjusted accordingly.

[0037] In one embodiment of this application, such as Figure 3 As shown, the voltage regulation module includes a third resistor R3 and a fourth resistor R4. The first end of the third resistor R3 is electrically connected to the output feedback module 101, and the second end of the third resistor R3 is electrically connected to the first end of the fourth resistor R4 and the operational amplifier module 103. The second end of the fourth resistor R4 is used to receive the injected voltage VADJ.

[0038] Specifically, the third resistor R3 and the fourth resistor R4 form a potential offset network. The third resistor R3 is used to connect the first node and the feedback node of the operational amplifier module 103, and the fourth resistor R4 is used to introduce an external injection voltage VADJ. The potential balance of the feedback node is changed by the injection voltage VADJ. In conjunction with the virtual open characteristic (almost no current flows into the input terminal of the operational amplifier module 103) and the virtual short characteristic (the feedback voltage VFB is equal to the reference voltage VREF) of the operational amplifier module 103, the third resistor R3 and the fourth resistor R4 form a current path. Changing the injection voltage VADJ can adjust the potential difference between the feedback node and the first node, thereby changing the first node voltage VFBO under steady state of the circuit, and finally realizing the continuous adjustment of the output voltage VOUT.

[0039] The first node voltage VFBO is calculated as follows: the ratio of the difference between the injected voltage VADJ and the reference voltage VREF to the resistance of the fourth resistor R4 is equal to the ratio of the difference between the reference voltage VREF and the first node voltage VFBO to the resistance of the third resistor R3, that is:

[0040] Therefore, the voltage VFBO of the first node is:

[0041] After sorting, we can obtain:

[0042] Combining the relationship between the first node voltage VFBO and the output voltage VOUT, we can obtain the output voltage VOUT as follows:

[0043] From the above formula, it can be seen that this application can adjust the first node voltage VFBO by introducing the injection voltage VADJ, the third resistor R3 and the fourth resistor R4, thereby adjusting the output voltage VOUT.

[0044] For example, when selecting the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4, appropriate resistance values ​​can be chosen based on the system's power consumption requirements. Selecting a larger resistance value can reduce the static current in each branch, thereby reducing the overall static power consumption of the circuit; selecting a smaller resistance value results in stronger anti-interference capabilities, and the voltage sampling and potential shift signals are less affected by external noise. Engineers can flexibly weigh the selection options based on the overall power consumption specifications and the electromagnetic environment.

[0045] It should be noted that in some application scenarios, if multiple fixed voltage regulation slopes are required, a third resistor R3 or a fourth resistor R4 with different resistance values ​​can be connected in parallel with a multi-switch. By selecting different resistors through the switch, the linear slope between the output voltage VOUT and the injected voltage VADJ can be switched. A single hardware platform can be compatible with multiple output voltage regulation specifications, facilitating the development of platform-based products.

[0046] In one embodiment of this application, such as Figure 3 As shown, the operational amplifier module 103 includes a first operational amplifier EA. The first input terminal (inverting input terminal) of the first operational amplifier EA is electrically connected to the voltage regulation module 102. The second input terminal (non-inverting input terminal) of the first operational amplifier EA is used to receive the reference voltage VREF. The output terminal of the first operational amplifier EA is used to output the adjustment signal.

[0047] Specifically, the first operational amplifier EA operates in the negative feedback linear region, possessing two core characteristics: virtual short and virtual open. The virtual open characteristic ensures almost no current flows into the inverting input of the first operational amplifier EA, preventing current shunting from the internal resistor branch of the voltage regulation module 102 and guaranteeing the validity of the potential relationship calculation. The virtual short characteristic ensures that the voltage at the inverting input (feedback voltage VFB) is approximately equal to the reference voltage VREF at the non-inverting input under steady-state conditions. The first operational amplifier EA continuously compares the feedback voltage VFB with the reference voltage VREF in real time. When the externally injected voltage VADJ changes, causing a voltage difference between the feedback voltage VFB and the reference voltage VREF, the first operational amplifier EA identifies this error and outputs an adjustment signal with a corresponding amplitude change. This adjustment signal is sent to the downstream power circuit, changing the operating state of the power circuit in real time, thereby adjusting the output voltage VOUT up or down, continuously reducing the difference between the feedback voltage VFB and the reference voltage VREF until they reappear equal. The entire voltage regulation loop establishes a new balance, ultimately maintaining a stable output state.

[0048] In one embodiment of this application, such as Figure 4 As shown, the adjustable output voltage control circuit also includes a unidirectional conduction module 104, which is electrically connected to the voltage regulation module 102 to prevent reverse voltage from being transmitted to the voltage regulation module 102.

[0049] Specifically, the unidirectional conduction module 104 is connected in series between the input terminal of the injected voltage VADJ and the voltage regulation module 102, allowing only the positive injected voltage VADJ to be transmitted to the voltage regulation module 102. When the external injected voltage VADJ port experiences abnormal conditions such as reverse polarity or negative voltage, the unidirectional conduction module 104 is turned off, blocking the reverse voltage and reverse current from flowing into the voltage regulation module 102, avoiding abnormal interference to the feedback node potential, preventing damage to internal circuits such as the operational amplifier module 103 from reverse voltage surges, and improving the reliability of the circuit operation.

[0050] In one embodiment of this application, such as Figure 4 As shown, the unidirectional conduction module 104 includes a first diode D1, the anode of the first diode D1 is used to receive the injected voltage VADJ, and the cathode of the first diode D1 is electrically connected to the voltage regulation module 102.

[0051] Specifically, the anode of the first diode D1 receives the injected voltage VADJ, and the cathode is connected to the voltage regulation module 102. When the injected voltage VADJ is a positive effective voltage, the first diode D1 conducts in the forward direction, transmitting the injected voltage VADJ normally to the voltage regulation module 102. If there are abnormal conditions such as negative voltage or reverse connection, the first diode D1 is reverse cut off, blocking the reverse voltage and reverse current from entering the voltage regulation module 102, avoiding abnormal disturbance of the feedback node potential and damage to the internal components of the operational amplifier module 103 by reverse voltage impact, and ensuring stable and reliable operation of the circuit.

[0052] Furthermore, when the external ADJ pin is plugged in or unplugged, or when the external injected voltage signal source unexpectedly loses power, if there is no unidirectional conduction module 104, the feedback voltage VFB will leak outward in reverse through the fourth resistor R4, causing the output voltage VOUT to run out of control. The first diode D1 can block the reverse current path, avoid voltage regulation failure caused by abnormal injected voltage signal source or plugging / unplugging, and improve the circuit's anti-interference capability in complex operating environments.

[0053] In one embodiment of this application, such as Figure 4 As shown, the adjustable output voltage control circuit also includes a voltage soft-start module 105, which is electrically connected to the voltage regulation module 102 and is used to adjust the soft-start time of the second node voltage. The second node voltage is the voltage at the common terminal of the voltage soft-start module 105 and the voltage regulation module 102.

[0054] Specifically, the voltage soft-start module 105 is used to regulate the rate of change of the second node voltage and set the soft-start time corresponding to the second node voltage. When the externally injected voltage VADJ changes, the voltage soft-start module 105 uses the RC charging and discharging characteristics to smooth the rise and fall slope of the second node voltage, avoids the sudden change of the injected voltage VADJ causing a sharp fluctuation in the feedback node potential, prevents the output voltage VOUT from jumping a large amount of time and generating surge current, and at the same time filters out the instantaneous voltage glitches at the input of the injected voltage VADJ, ensuring the smooth operation of the voltage regulation process and improving the working stability of the overall voltage regulation loop.

[0055] It should be noted that some electrical devices cannot withstand the impact of sudden voltage changes and only support a slow voltage ramp-up startup method. The voltage slow-start module 105 added in this application can smooth the slope of the injected voltage VADJ change, so that the output voltage VOUT can be smoothly adjusted without sudden rises and falls. Therefore, this circuit can be adapted to such load devices that only support slow power-up and prohibit voltage surge startup, thus broadening the circuit's applicable scenarios.

[0056] In one embodiment of this application, such as Figure 4 As shown, the voltage soft-start module 105 includes a fifth resistor R5 and a first capacitor C1. The first end of the fifth resistor R5 is electrically connected to the first end of the first capacitor C1 and the voltage regulation module 102, respectively. The second end of the fifth resistor R5 is used to receive the injected voltage VADJ, and the second end of the first capacitor C1 is grounded.

[0057] Specifically, the fifth resistor R5 and the first capacitor C1 form an RC delay network. The time constant of the RC network is determined by the resistance value of the fifth resistor R5 and the capacitance value of the first capacitor C1. Increasing the resistance or capacitance value can extend the soft-start time, and vice versa. Designers can freely select the device parameters according to the load requirements. The fifth resistor R5 acts as a current limiter and, together with the first capacitor C1, completes the charging and discharging process, smoothing the input injection voltage VADJ, slowing down the rate of change of voltage rise and fall, and avoiding drastic fluctuations in the feedback node potential caused by sudden changes in the injection voltage VADJ, thereby achieving smooth adjustment of the output voltage VOUT. At the same time, the first capacitor C1 can absorb instantaneous voltage spikes at the injection voltage VADJ terminal, filter out high-frequency interference, and prevent inrush current caused by sudden voltage changes, making it suitable for load devices that only support soft-start operation and cannot withstand voltage step changes.

[0058] It should be noted that in actual hardware circuits, PCB trace coupling interference and power supply ripple can introduce noise disturbances to the injected voltage and the first node voltage VFBO. In addition to relying on the first capacitor C1 in the voltage soft-start module 105 for filtering, an additional small filter capacitor can be added at the injected voltage VADJ location to further suppress high-frequency noise, prevent noise from causing erroneous adjustment of the op-amp module 103, and ensure long-term stability of the output voltage VOUT.

[0059] pass Figure 4 From the circuit diagram shown, the output voltage VOUT can be calculated as follows:

[0060] According to this formula, assuming the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, and the fifth resistor R5 are all selected, it can be determined that the output voltage VOUT has a definite linear relationship with the injected voltage VADJ. The output voltage VOUT will decrease as the injected voltage VADJ increases, as shown in the following formula:

[0061] Where a and b are constants uniquely determined by the resistance values ​​of the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, and the fifth resistor R5. The linear relationship between the output voltage VOUT and the injected voltage VADJ is shown in the figure below. Figure 5 As shown, as the injection voltage VADJ gradually increases, the output voltage VOUT decreases linearly, and the output voltage VOUT and the injection voltage VADJ have a negative linear relationship.

[0062] This application also discloses a chip including the adjustable output voltage control circuit provided in any of the above embodiments. The chip employing the adjustable output voltage control circuit provided in this application can flexibly adjust the output voltage through an externally input injection voltage, achieving dynamic voltage regulation without replacing the voltage divider resistor, thus significantly reducing product debugging and modification costs.

[0063] In addition, such as Figure 6 As shown, the chip exposes at least one voltage regulation control pin. That is, the chip can expose only a single voltage regulation control pin ADJ, or it can expose two voltage regulation control pins ADJ and FB at the same time to adapt to different hardware design requirements. Figure 4 The R3, R4, R5, C1, and D1 components can be used as a control strategy outside the chip or integrated into the chip as internal circuitry. When the components are placed outside the chip, users can modify the resistor and capacitor parameters according to actual application requirements, flexibly adjusting the voltage regulation slope and soft-start speed. When the components are integrated inside the chip, the number of peripheral components on the PCB can be reduced, and the overall board area of ​​the power supply solution can be reduced. Both implementation methods can be flexibly selected according to product positioning.

[0064] It should be noted that, as Figure 7As shown, the chip internally includes an input control module, an output control module, a drive control module, a feedback control module, and an adjustable output control module. The feedback control module is electrically connected to the adjustable output control module, the drive control module, and the output control module, respectively. The output control module is electrically connected to the input control module and the drive control module, respectively. Specifically, the input control module receives the input voltage and performs basic voltage regulation preprocessing. The output control module, in conjunction with an external energy storage element, generates the final output voltage. The drive control module receives the feedback voltage from the feedback control module and drives the power device to control the output voltage of the output control module. The feedback control module receives the output voltage and outputs a feedback voltage. The adjustable output control module, i.e., the aforementioned adjustable output voltage control circuit, dynamically adjusts the output voltage based on the injected voltage. All modules work together to form a complete closed-loop voltage regulation system, collaboratively achieving stable voltage output and voltage regulation control functions.

[0065] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0066] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. An adjustable output voltage control circuit, characterized in that, It includes an output feedback module, a voltage regulation module, and an operational amplifier module, wherein the voltage regulation module is electrically connected to the output feedback module and the operational amplifier module respectively; The output feedback module is used to acquire the output voltage and generate the first node voltage, and the operational amplifier module is used to receive the feedback voltage and the reference voltage and output the adjustment signal. The voltage regulation module is used to receive the injected voltage and adjust the first node voltage based on the injected voltage and the feedback voltage to regulate the output voltage.

2. The adjustable output voltage control circuit according to claim 1, characterized in that, The output voltage and the injection voltage have a negatively correlated linear relationship.

3. The adjustable output voltage control circuit according to claim 1, characterized in that, The output feedback module includes a first resistor and a second resistor. The first end of the first resistor is used to receive the output voltage. The second end of the first resistor is electrically connected to the first end of the second resistor and the voltage regulation module, respectively. The second end of the second resistor is grounded.

4. The adjustable output voltage control circuit according to claim 1, characterized in that, The voltage regulation module includes a third resistor and a fourth resistor. The first end of the third resistor is electrically connected to the output feedback module, and the second end of the third resistor is electrically connected to the first end of the fourth resistor and the operational amplifier module. The second end of the fourth resistor is used to receive the injected voltage. The ratio of the difference between the injected voltage and the reference voltage to the resistance of the fourth resistor is equal to the ratio of the difference between the reference voltage and the first node voltage to the resistance of the third resistor.

5. The adjustable output voltage control circuit according to claim 1, characterized in that, The operational amplifier module includes a first operational amplifier, the first input terminal of which is electrically connected to the voltage regulation module, the second input terminal of which is used to receive the reference voltage, and the output terminal of which is used to output the adjustment signal.

6. The adjustable output voltage control circuit according to any one of claims 1-5, characterized in that, The adjustable output voltage control circuit also includes a unidirectional conduction module, which is electrically connected to the voltage regulation module to prevent reverse voltage from being transmitted to the voltage regulation module.

7. The adjustable output voltage control circuit according to claim 6, characterized in that, The unidirectional conduction module includes a first diode, the anode of which is used to receive the injected voltage, and the cathode of which is electrically connected to the voltage regulation module.

8. The adjustable output voltage control circuit according to any one of claims 1-5, characterized in that, The adjustable output voltage control circuit further includes a voltage soft-start module, which is electrically connected to the voltage regulation module and is used to adjust the soft-start time of the second node voltage. The second node voltage is the voltage at the common terminal of the voltage soft-start module and the voltage regulation module.

9. The adjustable output voltage control circuit according to claim 8, characterized in that, The voltage soft-start module includes a fifth resistor and a first capacitor. The first end of the fifth resistor is electrically connected to the first end of the first capacitor and the voltage regulation module, respectively. The second end of the fifth resistor is used to receive the injected voltage, and the second end of the first capacitor is grounded.

10. A chip, characterized in that, The chip includes the adjustable output voltage control circuit according to any one of claims 1-9, wherein the chip has at least one voltage regulation control pin exposed to the outside; the voltage regulation control pin is used to connect the injected voltage.

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