Linear voltage regulated power supply circuits and electronic products

Abstract

The present application provides a linear voltage-regulated power supply circuit and electronic product. The linear voltage-regulated power supply circuit includes a low-voltage linear voltage-regulated circuit and a voltage-dividing sampling circuit. The voltage-dividing sampling circuit is connected between an input voltage source and the low-voltage linear voltage-regulated circuit. The voltage-dividing sampling circuit includes a first resistor network and a third transistor. The first resistor network is used to limit the current flowing into the low-voltage linear voltage-regulated circuit and provide a static operating point for the third transistor. The third transistor is used to share the voltage drop between the input voltage source and the low-voltage linear voltage-regulated circuit. The present application can expand the operating voltage range of the low-voltage linear voltage-regulated circuit.

Description

Technical Field

[0001] The present application relates to the field of power supply technology, and in particular to a linear voltage-regulated power supply circuit and an electronic product. Background Art

[0002] High-voltage, high-current, linearly adjustable regulated power supplies can be used to drive devices such as piezoelectric ceramics, and are also used in fields that require low-noise, high-voltage, and high-current drive. Piezoelectric ceramics are often used in precision positioning and ultrasonic transmitters, especially in scanning tunneling microscopes (STM), atomic force microscopes (AFM), and ultrasonic processing equipment. Piezoelectric ceramics require a high-voltage and stable driving power supply to ensure linear response and high-precision operation. At the same time, the power supply voltage needs to be adjustable to meet the needs of different applications. In the field of ultrasonic applications, ultrasonic transducers with piezoelectric ceramic elements as core components require a high-voltage, low-ripple power supply to generate stable ultrasonic signals and improve the signal-to-noise ratio of the results. In the field of quantum precision measurement, electro-optical modulators require high voltage electricity to be loaded onto electro-optical crystals to change the refractive index of the crystals, thereby controlling the modulation of the phase, amplitude, intensity, or polarization state of the optical signal. A linearly adjustable stable voltage is beneficial to improving the control accuracy of electro-optical crystals.

[0003] In the existing technology, high-voltage and high-current power supplies mostly use switching power supplies or simple linear regulators. However, switching power supplies are easily affected by electromagnetic interference and have large output ripple; while simple linear regulators have difficulty in achieving stable output of high voltage and high current. Summary of the Invention

[0004] The purpose of this application is to provide a linear voltage-regulated power supply circuit and an electronic product, which can at least partially solve the above-mentioned technical problems existing in the prior art.

[0005] One aspect of the present application provides a linear voltage-regulated power supply circuit. The linear voltage-regulated power supply circuit includes a low-voltage linear voltage-regulating circuit and a voltage-dividing sampling circuit, wherein the voltage-dividing sampling circuit is connected between an input voltage source and the low-voltage linear voltage-regulating circuit. The voltage-dividing sampling circuit includes a first resistor network and a third transistor, wherein the first resistor network is used to limit the current flowing into the low-voltage linear voltage-regulating circuit and provide a quiescent operating point for the third transistor; and the third transistor is used to share the voltage drop between the input voltage source and the low-voltage linear voltage-regulating circuit.

[0006] Furthermore, the low-voltage linear voltage regulator circuit has an input end, an output end and a regulation end, and the first resistor network includes a fourth resistor, a sixth resistor and a seventh resistor, wherein the fourth resistor is connected between the collector of the third transistor and the input voltage source; the sixth resistor is connected between the base of the third transistor and the input voltage source, and the seventh resistor is connected between the base of the third transistor and the regulation end of the low-voltage linear voltage regulator circuit; and the emitter of the third transistor is connected to the input end of the low-voltage linear voltage regulator circuit.

[0007] Furthermore, the low-voltage linear voltage regulator circuit includes a first transistor, a second transistor, a first resistor, a second resistor, a third resistor and a first voltage regulator, wherein the base of the first transistor is connected to the collector of the second transistor, the collector of the first transistor serves as the input end of the low-voltage linear voltage regulator circuit, and the emitter of the first transistor serves as the output end of the low-voltage linear voltage regulator circuit; the first resistor is connected between the base and the collector of the first transistor; the second resistor is connected between the emitter of the first transistor and the base of the second transistor; the third resistor is connected between the base of the second transistor and the regulating end of the low-voltage linear voltage regulator circuit; the anode of the first voltage regulator is connected to the regulating end of the low-voltage linear voltage regulator circuit, and the cathode of the first voltage regulator is connected to the emitter of the second transistor.

[0008] Furthermore, the linear voltage-regulated power supply circuit also includes an adjustable control circuit, wherein the adjustable control circuit is connected to the output end of the low-voltage linear voltage-regulated circuit and is used to adjust the output voltage of the low-voltage linear voltage-regulated circuit based on a reference voltage input source.

[0009] Furthermore, the adjustable control circuit includes an error amplifier circuit and a second resistor network, wherein the error amplifier circuit is used to connect to the reference voltage input source to adjust the output voltage of the low-voltage linear voltage regulator circuit; the second resistor network is used to sample the signal size of the output voltage of the low-voltage linear voltage regulator circuit and provide the operating point of the error amplifier circuit.

[0010] Furthermore, the error amplification circuit includes an operational amplifier, a first power supply, a second power supply, a fourth transistor, an eighth resistor, a ninth resistor and a first capacitor, wherein the non-inverting input terminal of the operational amplifier is connected to the second resistor network, the inverting input terminal of the operational amplifier is connected to the reference voltage input source and is connected to the output terminal of the operational amplifier through the first capacitor; the first power supply and the second power supply are connected to the operational amplifier as positive and negative power supplies, respectively; the base of the fourth transistor is connected to the output terminal of the operational amplifier through the eighth resistor, the collector of the fourth transistor is connected to the output terminal of the low-voltage linear voltage regulator circuit through the ninth resistor, and the emitter of the fourth transistor is grounded.

[0011] Furthermore, the second resistor network includes a tenth resistor and an eleventh resistor connected in series, wherein the tenth resistor and the eleventh resistor are connected in series between the output end of the low-voltage linear voltage regulator circuit and the ground, and the non-inverting input end of the operational amplifier is connected between the tenth resistor and the eleventh resistor.

[0012] Furthermore, the first resistor network also includes a fifth resistor connected in series with the fourth resistor, and the fourth resistor and the fifth resistor are used to limit the current flowing into the low-voltage linear voltage regulator circuit. The linear voltage regulated power supply circuit also includes a current expansion circuit, wherein the current expansion circuit is connected between the fourth resistor and the fifth resistor in the voltage divider sampling circuit, and the fourth resistor is used to sample the current flowing into the low-voltage linear voltage regulator circuit to control the operating point of the current expansion circuit; the current expansion circuit is also connected to the output end of the low-voltage linear voltage regulator circuit to increase the output current of the output end of the low-voltage linear voltage regulator circuit.

[0013] Furthermore, the current expansion circuit includes a common-collector amplifier circuit, and the common-collector amplifier circuit is composed of one or more power devices connected in parallel.

[0014] Furthermore, the current expansion circuit includes a fifth transistor, a sixth transistor, a twelfth resistor and a thirteenth resistor, wherein the base of the fifth transistor is connected to the collector of the sixth transistor and is connected to the regulating end of the low-voltage linear voltage regulator circuit through the twelfth resistor, the collector of the fifth transistor is connected to the emitter of the sixth transistor and is connected to the input voltage source, and the emitter of the fifth transistor is connected to the output end of the low-voltage linear voltage regulator circuit; the base of the sixth transistor is connected between the fourth resistor and the fifth resistor through the thirteenth resistor.

[0015] Furthermore, the fifth transistor includes an NPN Darlington transistor.

[0016] Another aspect of the present application provides an electronic product comprising the linear voltage-regulated power supply circuit described above.

[0017] The linear voltage-regulated power supply circuit and electronic product of one or more embodiments of the present application add a voltage-dividing sampling circuit and use an adjustable voltage-dividing method to make a low-voltage linear voltage-regulated circuit operate in a high-voltage circuit, thereby utilizing the low ripple and low noise characteristics of the low-voltage linear voltage-regulated circuit and expanding the operating voltage range of the low-voltage linear voltage-regulated circuit.

[0018] The linear voltage-regulated power supply circuit and the electronic product of one or more embodiments of the present application can make the output voltage of the low-voltage linear voltage-regulated circuit adjustable by introducing an adjustable control circuit.

[0019] The linear voltage-regulated power supply circuit and electronic product of one or more embodiments of the present application can greatly expand the output capacity of the low-voltage linear voltage-regulated circuit by adding a current expansion circuit, and can provide a large current output. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a structural block diagram of a linear voltage-regulated power supply circuit according to an embodiment of the present application.

[0021] Figure 2 This is a circuit diagram of a linear voltage-regulated power supply circuit according to an embodiment of the present application. DETAILED DESCRIPTION

[0022] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of devices consistent with certain aspects of the present application, as detailed in the appended claims.

[0023] The linear voltage regulated power supply circuit and electronic product of each embodiment of the present application are described in detail below with reference to the accompanying drawings. In the absence of conflict, the features of the following embodiments and implementations can be combined with each other.

[0024] Figure 1 The structure block diagram of a linear voltage regulated power supply circuit 100 according to an embodiment of the present application is disclosed. Figure 2 The circuit diagram of the linear voltage regulated power supply circuit 100 according to one embodiment of the present application is disclosed. Figure 1 and Figure 2 As shown, a linear voltage regulated power supply circuit 100 according to an embodiment of the present application includes a low-voltage linear voltage regulated circuit 110 and a voltage divider sampling circuit 120 .

[0025] The low-voltage linear regulator circuit 110 is the core circuit of the linear regulated power supply circuit 100. The low-voltage linear regulator circuit 110 can use either a commercial linear regulated power supply chip or a circuit constructed using discrete components. In one embodiment of the present application, the low-voltage linear regulator circuit 110 is constructed using discrete components to facilitate simulation.

[0026] The low voltage linear voltage regulator circuit 110 has an input terminal, an output terminal, and a regulating terminal. In some embodiments, the low voltage linear voltage regulator circuit 110 of the present application includes a first transistor Q1, a second transistor Q2, a first resistor R1, a second resistor R2, a third resistor R3, and a first voltage regulator tube D1.

[0027] The base of the first transistor Q1 is connected to the collector of the second transistor Q2. The collector of the first transistor Q1 serves as the input of the low-voltage linear voltage regulator circuit 110, and the emitter of the first transistor Q1 serves as the output of the low-voltage linear voltage regulator circuit 110. The first transistor Q1 serves as a power regulator and outputs current.

[0028] A first resistor R1 is connected between the base and collector of the first transistor Q1; a second resistor R2 is connected between the emitter of the first transistor Q1 and the base of the second transistor Q2; and a third resistor R3 is connected between the base of the second transistor Q2 and the regulating terminal of the low-voltage linear regulator circuit 110. The second resistor R2 and the third resistor R3 are used to sample the divided voltage of the output voltage Vo of the low-voltage linear regulator circuit 110 to regulate the base voltage of the second transistor Q2. The first resistor R1 is used to provide a quiescent operating point for the second transistor Q2.

[0029] The anode of the first voltage regulator D1 is connected to the regulating terminal of the low-voltage linear voltage regulator circuit 110, and the cathode of the first voltage regulator D1 is connected to the emitter of the second transistor Q2. The first voltage regulator D1 is used to provide a minimum stable voltage.

[0030] When the output voltage Vo of the low-voltage linear regulator circuit 110 increases, the voltage sampled and divided by the second resistor R2 and the third resistor R3 increases, and the base voltage of the second transistor Q2 increases. According to transistor characteristics, the current flowing through the second transistor Q2 increases, and the base voltage of the first transistor Q1 decreases, and the output voltage Vo of the low-voltage linear regulator circuit 110 decreases. As a result, the output voltage Vo of the low-voltage linear regulator circuit 110 can be kept constant and the output voltage Vo can be kept stable.

[0031] The voltage-dividing sampling circuit 120 is connected between the input voltage source V1 and the low-voltage linear regulator circuit 110. The voltage-dividing sampling circuit 120 may include a first resistor network and a third transistor Q3. The first resistor network is used to limit the current flowing into the low-voltage linear regulator circuit 110 and provide a quiescent operating point for the third transistor Q3. The third transistor Q3 is used to share the voltage drop between the input voltage source V1 and the low-voltage linear regulator circuit 110.

[0032] In some embodiments, the first resistor network may include a fourth resistor R4, a sixth resistor R6, and a seventh resistor R7.

[0033] The fourth resistor R4 is connected between the collector of the third transistor Q3 and the input voltage source V1 to limit the current flowing into the low voltage linear regulator circuit 110. The emitter of the third transistor Q3 is connected to the input terminal of the low voltage linear regulator circuit 110.

[0034] The sixth resistor R6 is connected between the base of the third transistor Q3 and the input voltage source V1, and the seventh resistor R7 is connected between the base of the third transistor Q3 and the regulating terminal of the low-voltage linear voltage regulator circuit 110. The sixth resistor R6 and the seventh resistor R7 are used to provide a static operating point for the third transistor Q3.

[0035] In some embodiments, the linear regulated power supply circuit 100 of the present application may further include an adjustable control circuit 130. The adjustable control circuit 130 is connected to the output terminal of the low-voltage linear regulated circuit 110 and is configured to adjust the output voltage Vo of the low-voltage linear regulated circuit 110 based on a reference voltage input source V2.

[0036] In some embodiments, the adjustable control circuit 130 of the present application may include an error amplifier circuit and a second resistor network. The error amplifier circuit is connected to a reference voltage input source V2 to adjust the output voltage Vo of the low-voltage linear regulator circuit 110. The second resistor network is used to sample the signal level of the output voltage Vo of the low-voltage linear regulator circuit 110 and provide an operating point for the error amplifier circuit.

[0037] In some embodiments, the error amplification circuit may include an operational amplifier U, a first power supply V3, a second power supply V4, a fourth transistor Q4, an eighth resistor R8, a ninth resistor R9, and a first capacitor C1.

[0038] The non-inverting input of operational amplifier U is connected to the second resistor network, while the inverting input of operational amplifier U is connected to a reference voltage input source V2 and to the output of operational amplifier U via a first capacitor C1. First capacitor C1 acts as an integrator, amplifying the voltage difference between the feedback voltage and the reference voltage input source V2. The reference voltage input source V2 can be generated by an external signal source or a digital-to-analog converter (DAC).

[0039] The first power supply V3 and the second power supply V4 are connected to the operational amplifier U as auxiliary positive and negative power supplies, respectively, so that the operational amplifier U can operate normally.

[0040] The base of the fourth transistor Q4 is connected to the output terminal of the operational amplifier U via an eighth resistor R8, and the eighth resistor R8 is used to limit the current flowing into the base of the fourth transistor Q4; the collector of the fourth transistor Q4 is connected to the output terminal of the low-voltage linear voltage regulator circuit 110 via a ninth resistor R9, and the ninth resistor R9 is used to provide a static operating point for the fourth transistor Q4; and the emitter of the fourth transistor Q4 is grounded.

[0041] In some embodiments, the second resistor network includes a tenth resistor R10 and an eleventh resistor R11 connected in series.

[0042] The tenth resistor R10 and the eleventh resistor R11 are connected in series between the output terminal of the low-voltage linear regulator circuit 110 and ground. The non-inverting input terminal of the operational amplifier U is connected between the tenth resistor R10 and the eleventh resistor R11. The tenth resistor R10 and the eleventh resistor R11 sample the final adjustable output voltage Vo and feed it back through the non-inverting input terminal of the operational amplifier U.

[0043] After the voltage of the reference voltage input source V2 is set, when the adjustable output voltage Vo of the low-voltage linear regulator circuit 110 increases, the voltage sampled and divided by the tenth resistor R10 and the eleventh resistor R11 increases, the voltage at the non-inverting input terminal of the operational amplifier U increases, and the output voltage Vo of the operational amplifier U increases. This increases the current flowing into the base of the fourth transistor Q4, reducing the voltage difference between the emitter and collector of the fourth transistor Q4. This reduces the reference ground voltage of the low-voltage linear regulator circuit 110, and therefore reduces the adjustable output voltage Vo of the low-voltage linear regulator circuit 110.

[0044] In some embodiments, the linear voltage-regulated power supply circuit 100 of the present application may further include a current expansion circuit 140. The first resistor network in the voltage-dividing sampling circuit 120 further includes a fifth resistor R5 connected in series with the fourth resistor R4. The fourth resistor R4 and the fifth resistor R5 are used to jointly limit the current flowing into the low-voltage linear voltage-regulated circuit 110.

[0045] The current expansion circuit 140 is connected between the fourth resistor R4 and the fifth resistor R5 in the voltage division sampling circuit 120 . The fourth resistor R4 is used to sample the current flowing into the low voltage linear regulator circuit 110 to control the operating point of the current expansion circuit 140 .

[0046] The current expansion circuit 140 is also connected to the output end of the low-voltage linear voltage regulator circuit 110 to increase the output current of the output end of the low-voltage linear voltage regulator circuit 110 and provide a large current output.

[0047] Optionally, the current expansion circuit 140 may include a common-collector amplifier circuit, which is composed of one or more power devices connected in parallel.

[0048] In some embodiments, the current expansion circuit 140 includes a fifth transistor Q5 , a sixth transistor Q6 , a twelfth resistor R12 , and a thirteenth resistor R13 .

[0049] The base of the fifth transistor Q5 is connected to the collector of the sixth transistor Q6 and connected to the regulating terminal of the low-voltage linear voltage regulator circuit 110 through the twelfth resistor R12. The collector of the fifth transistor Q5 is connected to the emitter of the sixth transistor Q6 and to the input voltage source V1. The emitter of the fifth transistor Q5 is connected to the output terminal of the low-voltage linear voltage regulator circuit 110. Optionally, the fifth transistor Q5 may include an NPN Darlington transistor to reduce the demand for base current. The fifth transistor Q5 can function as a power transistor and provide a high current output.

[0050] The base of the sixth transistor Q6 is connected between the fourth resistor R4 and the fifth resistor R5 via a thirteenth resistor R13. The sixth transistor Q6 can be, for example, a PNP transistor. The thirteenth resistor R13 is used to limit the current flowing into the base of the sixth transistor Q6. By sampling the voltage of the fourth resistor R4 in the voltage divider sampling circuit 120, a simple current source circuit is formed. The twelfth resistor R12 provides a current flow path.

[0051] When the current of the adjustable output voltage Vo of the low-voltage linear voltage regulator circuit 110 increases, the current flowing through the fourth resistor R4 in the voltage-dividing sampling circuit 120 increases, the base voltage of the sixth transistor Q6 decreases, the current flowing through the sixth transistor Q6 increases, the base voltage of the fifth transistor Q5 increases, and the base current flowing into the fifth transistor Q5 increases, thereby increasing the output capacity of the fifth transistor Q5. Thus, a high current output can be provided.

[0052] The linear voltage-regulated power supply circuit 100 of the present application can meet the requirements of high voltage, large current and low ripple, and solves the problems of low output current and unadjustable output voltage of high-voltage power supplies in the prior art.

[0053] Of course, it is understood that in other embodiments, to ensure that the linear voltage-regulated power supply circuit 100 of the present application can operate better, the linear voltage-regulated power supply circuit 100 of the present application may further include auxiliary modules such as a heat dissipation module, a protection module, and / or a loop stabilization compensation module. However, the linear voltage-regulated power supply circuit 100 of the present application is not limited to these auxiliary modules, and they may be appropriately added or reduced based on actual circuit application requirements.

[0054] For example, the resistance ratio of the tenth resistor R10 and the eleventh resistor R11 is set to 39:1, the gain coefficient is 40, the load resistor Ro is 500 ohms, and the input voltage source V1 is 120V. Figure 2 The linear voltage regulated power supply circuit 100 shown in FIG. 1 is simulated by Multisim. When the reference voltage input source V2 is 1V, the Figure 2 The adjustable output voltage Vo of the linear regulated power supply circuit 100 shown is 40V; when the reference voltage input source V2 is 2.5V, the Figure 2 The adjustable output voltage Vo of the linear voltage-regulated power supply circuit 100 shown is 100 V. Therefore, it can be seen from the above simulation that the linear voltage-regulated power supply circuit 100 of the present application can adjust the output voltage Vo according to the voltage of the reference voltage input source V2 by adding the adjustable control circuit 130, thereby achieving the adjustable output voltage Vo of the linear voltage-regulated power supply circuit 100 of the present application.

[0055] The present application also provides an electronic product, which includes the linear voltage-regulated power supply circuit 100 described in the above embodiments.

[0056] The linear voltage regulated power supply circuit 100 and the electronic product of one or more embodiments of the present application add a voltage divider sampling circuit 120, and use an adjustable voltage divider to make the low-voltage linear voltage regulated circuit 110 operate in a high-voltage circuit, thereby utilizing the low ripple and low noise characteristics of the low-voltage linear voltage regulated circuit 110 and expanding the operating voltage range of the low-voltage linear voltage regulated circuit 110.

[0057] The linear voltage regulated power supply circuit 100 and the electronic product of one or more embodiments of the present application can make the output voltage Vo of the low-voltage linear voltage regulated circuit 110 adjustable by introducing the adjustable control circuit 130 .

[0058] The linear voltage regulated power supply circuit 100 and the electronic product of one or more embodiments of the present application can greatly expand the output capacity of the low-voltage linear voltage regulated circuit 110 by adding the current expansion circuit 140, and can provide a large current output.

[0059] The above is a detailed introduction to the linear voltage-regulated power supply circuit and electronic product provided in the embodiments of the present application. Specific examples are used herein to illustrate the linear voltage-regulated power supply circuit and electronic product in the embodiments of the present application. The description of the above embodiments is only used to help understand the core idea of ​​the present application and is not intended to limit the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the spirit and principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications should also fall within the scope of protection of the claims attached to the present application.

Claims

1. A linear voltage-regulated power supply circuit, characterized in that: It includes a low-voltage linear voltage stabilization circuit and a voltage-dividing sampling circuit, wherein the voltage-dividing sampling circuit is connected between an input voltage source and the low-voltage linear voltage stabilization circuit, and the voltage-dividing sampling circuit includes a first resistor network and a third transistor, wherein: The first resistor network is used to limit the current flowing into the low-voltage linear voltage stabilization circuit and provide a static operating point for the third transistor; The third transistor is used to share the voltage drop between the input voltage source and the low-voltage linear voltage stabilization circuit. The low-voltage linear voltage stabilization circuit has an input terminal, an output terminal and a regulating terminal, and the first resistor network includes a fourth resistor, a sixth resistor and a seventh resistor, wherein: The fourth resistor is connected between the collector of the third transistor and the input voltage source; the sixth resistor is connected between the base of the third transistor and the input voltage source; and the seventh resistor is connected between the base of the third transistor and the regulating terminal of the low-voltage linear voltage regulator circuit; The emitter of the third transistor is connected to the input end of the low-voltage linear voltage stabilization circuit.

2. The linear voltage-regulated power supply circuit according to claim 1, wherein: The low-voltage linear voltage stabilizing circuit includes a first triode, a second triode, a first resistor, a second resistor, a third resistor and a first voltage stabilizing tube, wherein: The base of the first transistor is connected to the collector of the second transistor, the collector of the first transistor serves as the input end of the low-voltage linear voltage regulator circuit, and the emitter of the first transistor serves as the output end of the low-voltage linear voltage regulator circuit; The first resistor is connected between the base and the collector of the first transistor; The second resistor is connected between the emitter of the first transistor and the base of the second transistor; The third resistor is connected between the base of the second transistor and the regulating terminal of the low-voltage linear voltage stabilizing circuit; The anode of the first voltage regulator tube is connected to the regulating end of the low-voltage linear voltage regulator circuit, and the cathode of the first voltage regulator tube is connected to the emitter of the second transistor.

3. The linear voltage-regulated power supply circuit according to claim 1, wherein: It also includes an adjustable control circuit, wherein the adjustable control circuit is connected to the output end of the low-voltage linear voltage regulator circuit and is used to adjust the output voltage of the low-voltage linear voltage regulator circuit based on a reference voltage input source.

4. The linear voltage-regulated power supply circuit according to claim 3, wherein: The adjustable control circuit includes an error amplifier circuit and a second resistor network, wherein: The error amplifier circuit is used to be connected to the reference voltage input source and is used to adjust the output voltage of the low-voltage linear voltage regulator circuit; The second resistor network is used to sample the signal size of the output voltage of the low-voltage linear voltage regulator circuit and provide the operating point of the error amplifier circuit.

5. The linear voltage-regulated power supply circuit according to claim 4, wherein: The error amplification circuit includes an operational amplifier, a first power supply, a second power supply, a fourth transistor, an eighth resistor, a ninth resistor and a first capacitor, wherein: The non-inverting input terminal of the operational amplifier is connected to the second resistor network, and the inverting input terminal of the operational amplifier is connected to the reference voltage input source and connected to the output terminal of the operational amplifier through the first capacitor; The first power supply and the second power supply are connected to the operational amplifier as positive and negative power supplies respectively; The base of the fourth transistor is connected to the output end of the operational amplifier through the eighth resistor, the collector of the fourth transistor is connected to the output end of the low-voltage linear voltage regulator circuit through the ninth resistor, and the emitter of the fourth transistor is grounded.

6. The linear voltage-regulated power supply circuit according to claim 5, wherein: The second resistor network includes a tenth resistor and an eleventh resistor connected in series, wherein: The tenth resistor and the eleventh resistor are connected in series between the output end of the low-voltage linear voltage stabilizing circuit and the ground. The non-inverting input terminal of the operational amplifier is connected between the tenth resistor and the eleventh resistor.

7. The linear voltage-regulated power supply circuit according to claim 1, wherein: The first resistor network further includes a fifth resistor connected in series with the fourth resistor, and the fourth resistor and the fifth resistor are used to limit the current flowing into the low-voltage linear voltage regulator circuit. The linear voltage-regulated power supply circuit further includes a current expansion circuit, wherein: The current expansion circuit is connected between the fourth resistor and the fifth resistor in the voltage division sampling circuit, and the fourth resistor is used to sample the current flowing into the low-voltage linear voltage stabilization circuit to control the operating point of the current expansion circuit; The current expansion circuit is also connected to the output end of the low-voltage linear voltage stabilization circuit, and is used to increase the output current of the output end of the low-voltage linear voltage stabilization circuit.

8. The linear voltage-regulated power supply circuit according to claim 7, wherein: The current expansion circuit includes a common collector amplifier circuit, and the common collector amplifier circuit is composed of one or more power devices connected in parallel.

9. The linear voltage-regulated power supply circuit according to claim 7, wherein: The current expansion circuit includes a fifth transistor, a sixth transistor, a twelfth resistor and a thirteenth resistor, wherein: The base of the fifth transistor is connected to the collector of the sixth transistor and is connected to the regulating end of the low-voltage linear voltage regulator circuit through the twelfth resistor. The collector of the fifth transistor is connected to the emitter of the sixth transistor and is connected to the input voltage source. The emitter of the fifth transistor is connected to the output end of the low-voltage linear voltage regulator circuit. The base of the sixth transistor is connected between the fourth resistor and the fifth resistor through the thirteenth resistor.

10. The linear voltage-regulated power supply circuit according to claim 9, wherein: The fifth transistor includes an NPN Darlington transistor.

11. An electronic product, characterized in that: The method comprises the linear voltage-regulated power supply circuit according to any one of claims 1 to 10.

Images