TWI838141B - Boost converter with high power factor - Google Patents

Abstract

A boost converter with a high power factor includes a bridge rectifier, a boost inductor, a power switch element, an output stage circuit, a feedback compensation circuit, a multiplier, and a detection and control circuit. The bridge rectifier generates a rectified voltage according to a first input voltage and a second input voltage. The boost inductor receives the rectified voltage. The output stage circuit is coupled to the boost inductor, and is configured to generate an output voltage. The feedback compensation circuit generates a feedback voltage according to the output voltage. The multiplier generates a product voltage difference according to the rectified voltage and the feedback voltage. The product voltage difference is applied to the boost inductor. The detection and control circuit controls the multiplier according to the rectified voltage, the product voltage difference, and a communication voltage, so as to selectively update and increase the aforementioned product voltage difference.

Description

High Power Factor Boost Converter

The present invention relates to a boost converter, and in particular to a high power factor boost converter.

The boost converter is an indispensable component in the field of laptop computers. However, if the power factor of the boost converter is insufficient, it is easy to cause the overall operating performance of the related laptop to decline. In view of this, it is necessary to propose a new solution to overcome the difficulties faced by the previous technology.

In a preferred embodiment, the present invention provides a high power factor boost converter, comprising: a bridge rectifier, generating a rectified potential according to a first input potential and a second input potential; a boost inductor, receiving the rectified potential; a power switch, selectively coupling the boost inductor to a ground potential according to a pulse width modulation potential; an output stage circuit, coupled to the boost inductor, and generating an output potential; a feedback compensation circuit, generating a power factor according to the output potential; A multiplier is provided for generating a feedback potential according to the rectified potential and the feedback potential, wherein the product potential difference is applied to the boost inductor so that an inductor current flows through the boost inductor; and a detection and control circuit is provided for generating the pulse width modulation potential according to the feedback potential; wherein the detection and control circuit is further provided for controlling the multiplier according to the rectified potential, the product potential difference, and a communication potential to selectively update and enhance the product potential difference.

In some embodiments, if a maximum value of the product potential difference is lower than a critical value corresponding to an average value of the rectified potential, the detection and control circuit will control the multiplier to update the product potential difference by amplifying the product potential difference by a gain factor.

In some embodiments, the bridge rectifier includes: a first diode having an anode and a cathode, wherein the anode of the first diode is coupled to a first input node to receive the first input potential, and the cathode of the first diode is coupled to a first node to output the rectified potential; a second diode having an anode and a cathode, wherein the anode of the second diode is coupled to a second input node to receive the second input potential, and the cathode of the second diode is coupled to the first node; a third diode having a an anode and a cathode, wherein the anode of the third diode is coupled to the ground potential, and the cathode of the third diode is coupled to the first input node; and a fourth diode having an anode and a cathode, wherein the anode of the fourth diode is coupled to the ground potential, and the cathode of the fourth diode is coupled to the second input node; wherein the boost inductor has a first end and a second end, the first end of the boost inductor is coupled to the first node, and the second end of the boost inductor is coupled to a second node.

In some embodiments, the power switch includes: a switching transistor having a control end, a first end, and a second end, wherein the control end of the switching transistor is used to receive the pulse width modulation potential, the first end of the switching transistor is coupled to the ground potential, and the second end of the switching transistor is coupled to the second node.

In some embodiments, the output stage circuit includes: a fifth diode having an anode and a cathode, wherein the anode of the fifth diode is coupled to the second node, and the cathode of the fifth diode is coupled to an output node to output the output potential; and a first capacitor having a first end and a second end, wherein the first end of the first capacitor is coupled to the output node, and the second end of the first capacitor is coupled to the ground potential.

In some embodiments, the feedback compensation circuit includes: a first resistor having a first end and a second end, wherein the first end of the first resistor is coupled to the output node to receive the output potential, and the second end of the first resistor is coupled to a third node; a second resistor having a first end and a second end, wherein the first end of the second resistor is coupled to the third node, and the second end of the second resistor is coupled to a common node. a common node; a second capacitor having a first end and a second end, wherein the first end of the second capacitor is coupled to a fourth node, and the second end of the second capacitor is coupled to the third node; and a voltage regulator having an anode, a cathode, and a reference end, wherein the anode of the voltage regulator is coupled to the common node, the cathode of the voltage regulator is coupled to the fourth node, and the reference end of the voltage regulator is coupled to the third node.

In some embodiments, the feedback compensation circuit further includes: a linear optical coupler, including a light emitting diode and a bipolar junction transistor, wherein the light emitting diode has an anode and a cathode, the anode of the light emitting diode is coupled to the output node, the cathode of the light emitting diode is coupled to the fourth node, and the bipolar junction transistor has a collector. and an emitter, the collector of the bipolar junction transistor is used to output the feedback potential, and the emitter of the bipolar junction transistor is coupled to a fifth node; and a third capacitor having a first end and a second end, wherein the first end of the third capacitor is coupled to the fifth node, and the second end of the third capacitor is coupled to the ground potential.

In some embodiments, the detection and control circuit includes: an averaging circuit that calculates an average value of the rectified potential to generate an average potential.

In some embodiments, the detection and control circuit further includes: a microcontroller that receives the average potential and generates the pulse width modulation potential according to the feedback potential, wherein the microcontroller further monitors the product potential difference to obtain a maximum value of the product potential difference.

In some embodiments, the microcontroller determines whether to update and increase the product potential difference of the multiplier based on the average value of the rectified potential and the maximum value of the product potential difference.

In order to make the purpose, features and advantages of the present invention more clearly understood, specific embodiments of the present invention are specifically listed below and described in detail with reference to the accompanying drawings.

Certain terms are used in the specification and patent application to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. This specification and patent application do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criterion for distinction. The words "include" and "including" mentioned throughout the specification and patent application are open terms and should be interpreted as "including but not limited to". The word "substantially" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and achieve the basic technical effect. In addition, the word "coupled" in this specification includes any direct and indirect electrical connection means. Therefore, if a first device is described herein as being coupled to a second device, it means that the first device may be directly electrically connected to the second device, or may be indirectly electrically connected to the second device via other devices or connection means.

FIG. 1 is a schematic diagram of a boost converter 100 according to an embodiment of the present invention. For example, the boost converter 100 may be applied to a desktop computer, a laptop computer, or an all-in-one computer. As shown in FIG. 1 , the boost converter 100 includes: a bridge rectifier 110, a boost inductor LU, a power switch 120, an output stage circuit 130, a feedback compensation circuit 140, a multiplier 150, and a detection and control circuit 160. It should be noted that, although not shown in FIG. 1 , the boost converter 100 may further include other components, such as: a voltage regulator or (and) a negative feedback circuit.

The bridge rectifier 110 can generate a rectified potential VR according to a first input potential VIN1 and a second input potential VIN2, wherein an AC voltage with any frequency and any amplitude can be formed between the first input potential VIN1 and the second input potential VIN2. For example, the frequency of the AC voltage can be approximately 50 Hz or 60 Hz, and the root mean square (RMS) value of the AC voltage can be approximately between 90 V and 264 V, but is not limited thereto. The boost inductor LU can receive the rectified potential VR. The power switch 120 can selectively couple the boost inductor LU to a ground potential VSS (e.g., 0 V) according to a pulse width modulation (PWM) potential VM. For example, if the pulse width modulation potential VM is a high logic level (i.e., logic "1"), the power switch 120 can couple the boost inductor LU to the ground potential VSS (i.e., the power switch 120 can be similar to a short circuit path); conversely, if the pulse width modulation potential VM is a low logic level (i.e., logic "0"), the power switch 120 will not couple the boost inductor LU to the ground potential VSS (i.e., the power switch 120 can be similar to an open circuit path). The output stage circuit 130 is coupled to the boost inductor LU and can be used to generate an output potential VOUT. For example, the output potential VOUT may be a DC potential, and its potential level may be between 360V and 440V, but is not limited thereto. The feedback compensation circuit 140 may generate a feedback potential VF according to the output potential VOUT. The multiplier 150 may generate a product potential difference ΔV according to the rectified potential VR and the feedback potential VF, wherein the product potential difference ΔV may be applied to the boost inductor LU, so that an inductor current IL may flow through the boost inductor LU. The detection and control circuit 160 may generate a pulse width modulation potential VM according to the feedback potential VF. In addition, the detection and control circuit 160 can also control the multiplier 150 according to the rectified potential VR, the product potential difference ΔV, and a communication potential VC to selectively update and enhance the aforementioned product potential difference ΔV. For example, the communication potential VC can come from a system end (not shown), which can be regarded as an external control potential. In some embodiments, if a maximum value of the product potential difference ΔV is lower than a critical value corresponding to an average value of the rectified potential VR, the detection and control circuit 160 will control the multiplier 150 to update the product potential difference ΔV by amplifying the product potential difference ΔV by a gain factor K; otherwise, the detection and control circuit 160 will not change the product potential difference ΔV of the multiplier 150. However, the present invention is not limited thereto. According to actual measurement results, the boost converter 100 of the present invention can automatically track and optimize its own power factor, thereby maintaining good overall conversion efficiency.

The following embodiments will introduce the detailed structure and operation of the boost converter 100. It must be understood that these drawings and descriptions are only examples and are not intended to limit the scope of the present invention.

FIG. 2 is a circuit diagram of a boost converter 200 according to an embodiment of the present invention. In the embodiment of FIG. 2, the boost converter 200 has a first input node NIN1, a second input node NIN2, and an output node NOUT, and includes a bridge rectifier 210, a boost inductor LU, a power switch 220, an output stage circuit 230, a feedback compensation circuit 240, a multiplier 250, and a detection and control circuit 260. The first input node NIN1 and the second input node NIN2 of the boost converter 200 can be used to receive a first input potential VIN1 and a second input potential VIN2 respectively from an external input power source (not shown). The output node NOUT of the boost converter 200 can be used to output an output potential VOUT to a system end (not shown).

The bridge rectifier 210 includes a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4. The first diode D1 has an anode and a cathode, wherein the anode of the first diode D1 is coupled to the first input node NIN1, and the cathode of the first diode D1 is coupled to a first node N1 to output a rectified potential VR. The second diode D2 has an anode and a cathode, wherein the anode of the second diode D2 is coupled to the second input node NIN2, and the cathode of the second diode D2 is coupled to the first node N1. The third diode D3 has an anode and a cathode, wherein the anode of the third diode D3 is coupled to a ground potential VSS, and the cathode of the third diode D3 is coupled to the first input node NIN1. The fourth diode D4 has an anode and a cathode, wherein the anode of the fourth diode D4 is coupled to the ground potential VSS, and the cathode of the fourth diode D4 is coupled to the second input node NIN2.

The boost inductor LU has a first terminal and a second terminal, wherein the first terminal of the boost inductor LU is coupled to the first node N1 to receive the rectified potential VR, and the second terminal of the boost inductor LU is coupled to a second node N2.

The power switch 220 includes a switching transistor MS. For example, the switching transistor MS may be an N-type metal-oxide-semiconductor field-effect transistor (NMOSFET). The switching transistor MS has a control terminal (e.g., a gate), a first terminal (e.g., a source), and a second terminal (e.g., a drain), wherein the control terminal of the switching transistor MS is used to receive a pulse width modulation potential VM, the first terminal of the switching transistor MS is coupled to the ground potential VSS, and the second terminal of the switching transistor MS is coupled to the second node N2.

The output stage circuit 230 includes a fifth diode D5 and a first capacitor C1. The fifth diode D5 has an anode and a cathode, wherein the anode of the fifth diode D5 is coupled to the second node N2, and the cathode of the fifth diode D5 is coupled to the output node NOUT. The first capacitor C1 has a first terminal and a second terminal, wherein the first terminal of the first capacitor C1 is coupled to the output node NOUT, and the second terminal of the first capacitor C1 is coupled to the ground potential VSS.

In some embodiments, the feedback compensation circuit 240 includes a voltage regulator 242, a linear optical coupler 244, a second capacitor C2, a third capacitor C3, a first resistor R1, and a second resistor R2.

The first resistor R1 has a first end and a second end, wherein the first end of the first resistor R1 is coupled to the output node NOUT to receive the output potential VOUT, and the second end of the first resistor R1 is coupled to a third node N3. The second resistor R2 has a first end and a second end, wherein the first end of the second resistor R2 is coupled to the third node N3, and the second end of the second resistor R2 is coupled to a common node NCM. It must be understood that the common node NCM can be regarded as another ground potential, which can be the same as or different from the aforementioned ground potential VSS. The second capacitor C2 has a first end and a second end, wherein the first end of the second capacitor C2 is coupled to a fourth node N4, and the second end of the second capacitor C2 is coupled to the third node N3.

In some embodiments, the voltage regulator 242 is implemented by a TL431 electronic component. The voltage regulator 242 has an anode, a cathode, and a reference terminal, wherein the anode of the voltage regulator 242 is coupled to the common node NCM, the cathode of the voltage regulator 242 is coupled to the fourth node N4, and the reference terminal of the voltage regulator 242 is coupled to the third node N3.

In some embodiments, the linear optical coupler 244 is implemented by a PC817 electronic component. The linear optical coupler 244 includes a light emitting diode DL and a bipolar junction transistor Q1 (e.g., NPN type). The light emitting diode DL has an anode and a cathode, wherein the anode of the light emitting diode DL is coupled to the output node NOUT to receive the output potential VOUT, and the cathode of the light emitting diode DL is coupled to the fourth node N4. The bipolar junction transistor Q1 has a collector and an emitter, wherein the collector of the bipolar junction transistor Q1 is used to output a feedback potential VF, and the emitter of the bipolar junction transistor Q1 is coupled to a fifth node N5.

In addition, the third capacitor C3 has a first terminal and a second terminal, wherein the first terminal of the third capacitor C3 is coupled to the fifth node N5, and the second terminal of the third capacitor C3 is coupled to the ground potential VSS.

The multiplier 250 can generate a product potential difference ΔV according to the rectified potential VR and the feedback potential VF, wherein the product potential difference ΔV can be applied to the boost inductor LU, so that an inductor current IL can flow through the boost inductor LU. That is, a potential difference between the first node N1 and the second node N2 is equal to the aforementioned product potential difference ΔV. In some embodiments, the product potential difference ΔV of the multiplier 250 can be determined according to the following equation (1):

……………………………………(1) “ΔV” represents the size of the product potential difference ΔV, “VR” represents the level of the rectified potential VR, and “VF” represents the level of the feedback potential VF.

The detection and control circuit 260 includes an average circuit 262 and a microcontroller unit (MCU) 264. The microcontroller 264 is coupled to the average circuit 262, wherein the microcontroller 264 can generate a pulse width modulation potential VM according to the feedback potential VF.

The averaging circuit 262 can calculate an average value of the rectified potential VR within a given period of time to generate an average potential VA. The microcontroller 264 can receive the average potential VA to obtain the average value of the rectified potential VR. In addition, the microcontroller 264 can continuously monitor the product potential difference ΔV to obtain a maximum value of the product potential difference ΔV within another given period of time. Generally speaking, the microcontroller 264 can control the multiplier 250 based on the average value of the rectified potential VR and the maximum value of the product potential difference ΔV to determine whether to update and increase the product potential difference ΔV of the multiplier 250. It must be understood that if the product potential difference ΔV of the multiplier 250 has been updated and increased by the microcontroller 264, it will not satisfy the aforementioned equation (1).

FIG. 3 is a schematic diagram showing a system end 300 according to an embodiment of the present invention. The system end 300 may be indirectly powered by the boost converter 200. In the embodiment of FIG. 3 , the system end 300 includes a mother board (MB) 310 and an embedded controller (EC) 320, wherein the embedded controller 320 may be disposed on the mother board 310. The embedded controller 320 of the system end 300 may communicate with the microcontroller 264 of the boost converter 200, wherein a communication potential VC may be transmitted between the microcontroller 264 and the embedded controller 320. By analyzing the communication potential VC, the embedded controller 320 may obtain the average value of the rectified potential VR and the maximum value of the product potential difference ΔV. In some embodiments, the embedded controller 320 may store a lookup table 330, which may be as follows:

Required power factor Average value of rectified potential VR The corresponding critical value 0.95 90V 50V 0.95 110V 61V 0.95 130V 72V 0.95 150V 83V 0.95 170V 94V 0.95 190V 105V 0.95 210V 116V 0.95 230V 127V 0.95 250V 138V Table 1: Comparison table of embedded controllers

The embedded controller 320 can query its comparison table 330 based on the information of the communication potential VC. It must be understood that the content of this comparison table 330 is only an example, and it can also be adjusted according to different needs. If the maximum value of the product potential difference ΔV is lower than the critical value corresponding to the average value of the rectified potential VR, it means that the required power factor cannot be maintained. At this time, the embedded controller 320 will instruct the microcontroller 264 to control the multiplier 250 and update its product potential difference ΔV. For example, the microcontroller 264 can update the product potential difference ΔV of the multiplier 250 by amplifying the original product potential difference ΔV by a gain factor K. For example, the gain factor K can be any positive number greater than 1. In some embodiments, the product potential difference ΔV can be updated according to the following equation (2):

………………………………………(2) Wherein “ΔV” represents the size of the original product potential difference ΔV before updating, “ΔV′” represents the size of the product potential difference ΔV after updating, and “K” represents the gain multiplier K of the microcontroller 264.

On the contrary, if the maximum value of the product potential difference ΔV is higher than or equal to the critical value corresponding to the average value of the rectified potential VR, it means that the required power factor can be maintained, and the microcontroller 264 does not need to change the product potential difference ΔV of the multiplier 250. However, the present invention is not limited to this. In other embodiments, the microcontroller 264 can also store the aforementioned comparison table 330, which can determine whether to update the product potential difference ΔV of the multiplier 250 without communicating with the system end 300.

FIG. 4 is a potential waveform diagram of the boost converter 200 according to an embodiment of the present invention, wherein the horizontal axis represents time and the vertical axis represents potential level. As shown in FIG. 4, a first curve CC1 can represent the potential waveform of the rectified potential VR, a second curve CC2 can represent the potential waveform of the product potential difference ΔV before updating, and a third curve CC3 can represent the potential waveform of the product potential difference ΔV after updating. As mentioned above, if the embedded controller 320 or the microcontroller 264 determines that the maximum value of the product potential difference ΔV is lower than the critical value corresponding to the average value of the rectified potential VR, it means that the required power factor cannot be maintained. At this time, the microcontroller 264 can update the product potential difference ΔV of the multiplier 250 by amplifying the original product potential difference ΔV by the gain factor K. In other words, the potential waveform of the product potential difference ΔV will be transformed from the second curve CC2 to the third curve CC3, so that the boost converter 200 can maintain a relatively high power factor. Therefore, even if the boost converter 200 is affected by non-ideal factors (for example, too large process error or too high operating temperature), it can still be automatically adjusted to improve its power factor and enhance the overall conversion efficiency.

The present invention proposes a novel boost converter. According to actual measurement results, the boost converter using the above design can maintain a relatively high power factor, so it is very suitable for application in various devices.

It is worth noting that the potential, current, resistance, inductance, capacitance, and other component parameters described above are not limiting conditions of the present invention. Designers can adjust these settings according to different needs. The boost converter of the present invention is not limited to the states shown in Figures 1-4. The present invention may include only one or more features of any one or more embodiments of Figures 1-4. In other words, not all of the features shown in the diagrams need to be implemented in the boost converter of the present invention at the same time. Although the embodiments of the present invention use metal oxide semi-conductor field effect transistors as an example, the present invention is not limited to this. People skilled in the art can use other types of transistors, such as junction field effect transistors, or fin field effect transistors, etc., without affecting the effects of the present invention.

Ordinal numbers in this specification and the scope of the patent application, such as "first", "second", "third", etc., have no sequential relationship with each other, and are only used to mark and distinguish two different components with the same name.

Although the present invention is disclosed as above with the preferred embodiments, it is not intended to limit the scope of the present invention. Anyone skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the attached patent application.

100,200: Boost converter 110,210: Bridge rectifier 120,220: Power switch 130,230: Output stage circuit 140,240: Feedback compensation circuit 150,250: Multiplier 160,260: Detection and control circuit 242: Voltage regulator 244: Linear optocoupler 262: Averaging circuit 264: Microcontroller 300: System side 310: Main circuit board 320: Embedded controller 330: Comparison table C1: First capacitor C2: Second capacitor C3: Third capacitor CC1: First curve CC2: Second curve CC3: Third curve D1: First diode D2: second diode D3: third diode D4: fourth diode D5: fifth diode DL: light-emitting diode IL: inductor current K: gain ratio LU: boost inductor MS: switching transistor N1: first node N2: second node N3: third node N4: fourth node N5: fifth node NCM: common node NIN1: first input node NIN2: second input node NOUT: output node Q1: bipolar junction transistor R1: first resistor R2: second resistor VA: average potential VC: communication potential VF: feedback potential VIN1: first input potential VIN2: second input potential VM: pulse width modulation potential VOUT: output potential VR: rectified potential VSS: ground potential ΔV: product potential difference

FIG. 1 is a schematic diagram showing a boost converter according to an embodiment of the present invention. FIG. 2 is a circuit diagram showing a boost converter according to an embodiment of the present invention. FIG. 3 is a schematic diagram showing a system end according to an embodiment of the present invention. FIG. 4 is a potential waveform diagram showing a boost converter according to an embodiment of the present invention.

100:Boost converter

110: Bridge rectifier

120: Power switch

130: Output stage circuit

140: Feedback compensation circuit

150:Multiplier

160: Detection and control circuit

IL: Inductor current

K: gain multiplier

LU: Boost Inductor

VC: Communication potential

VF: Feedback potential

VIN1: first input potential

VIN2: Second input potential

VM: Pulse Width Modulation Potential

VOUT: output voltage

VR: Rectification potential

VSS: ground potential

△V: product potential difference

Claims (10)

A high power factor boost converter includes: a bridge rectifier, generating a rectified potential according to a first input potential and a second input potential; a boost inductor, receiving the rectified potential; a power switch, selectively coupling the boost inductor to a ground potential according to a pulse width modulation potential; an output stage circuit, coupled to the boost inductor, and generating an output potential; a feedback compensation circuit, generating a feedback potential according to the output potential; a multiplier, generating a product potential difference according to the rectified potential and the feedback potential, wherein the product potential difference is applied to the boost inductor, so that an inductor current will flow through the boost inductor; and A detection and control circuit generates the pulse width modulation potential according to the feedback potential; wherein the detection and control circuit further controls the multiplier according to the rectified potential, the product potential difference, and a communication potential to selectively update and enhance the product potential difference. In the boost converter of claim 1, if a maximum value of the product potential difference is lower than a critical value corresponding to an average value of the rectified potential, the detection and control circuit will control the multiplier to update the product potential difference by amplifying the product potential difference by a gain factor. A boost converter as claimed in claim 1, wherein the bridge rectifier comprises: a first diode having an anode and a cathode, wherein the anode of the first diode is coupled to a first input node to receive the first input potential, and the cathode of the first diode is coupled to a first node to output the rectified potential; a second diode having an anode and a cathode, wherein the anode of the second diode is coupled to a second input node to receive the second input potential, and the cathode of the second diode is coupled to the first node; A third diode having an anode and a cathode, wherein the anode of the third diode is coupled to the ground potential, and the cathode of the third diode is coupled to the first input node; and A fourth diode having an anode and a cathode, wherein the anode of the fourth diode is coupled to the ground potential, and the cathode of the fourth diode is coupled to the second input node; wherein the boost inductor has a first end and a second end, the first end of the boost inductor is coupled to the first node, and the second end of the boost inductor is coupled to a second node. A boost converter as claimed in claim 3, wherein the power switch comprises: A switching transistor having a control end, a first end, and a second end, wherein the control end of the switching transistor is used to receive the pulse width modulation potential, the first end of the switching transistor is coupled to the ground potential, and the second end of the switching transistor is coupled to the second node. A boost converter as claimed in claim 3, wherein the output stage circuit comprises: a fifth diode having an anode and a cathode, wherein the anode of the fifth diode is coupled to the second node, and the cathode of the fifth diode is coupled to an output node to output the output potential; and a first capacitor having a first end and a second end, wherein the first end of the first capacitor is coupled to the output node, and the second end of the first capacitor is coupled to the ground potential. A boost converter as claimed in claim 5, wherein the feedback compensation circuit comprises: a first resistor having a first end and a second end, wherein the first end of the first resistor is coupled to the output node to receive the output potential, and the second end of the first resistor is coupled to a third node; a second resistor having a first end and a second end, wherein the first end of the second resistor is coupled to the third node, and the second end of the second resistor is coupled to a common node; a second capacitor having a first end and a second end, wherein the first end of the second capacitor is coupled to a fourth node, and the second end of the second capacitor is coupled to the third node; and A voltage regulator has an anode, a cathode, and a reference terminal, wherein the anode of the voltage regulator is coupled to the common node, the cathode of the voltage regulator is coupled to the fourth node, and the reference terminal of the voltage regulator is coupled to the third node. The boost converter of claim 6, wherein the feedback compensation circuit further comprises: A linear optical coupler, comprising a light-emitting diode and a bipolar junction transistor, wherein the light-emitting diode has an anode and a cathode, the anode of the light-emitting diode is coupled to the output node, the cathode of the light-emitting diode is coupled to the fourth node, the bipolar junction transistor has a collector and an emitter, the collector of the bipolar junction transistor is used to output the feedback potential, and the emitter of the bipolar junction transistor is coupled to a fifth node; and A third capacitor having a first end and a second end, wherein the first end of the third capacitor is coupled to the fifth node, and the second end of the third capacitor is coupled to the ground potential. A boost converter as claimed in claim 1, wherein the detection and control circuit comprises: An averaging circuit that calculates an average value of the rectified potential to generate an average potential. The boost converter of claim 8, wherein the detection and control circuit further comprises: A microcontroller, receiving the average potential and generating the pulse width modulation potential according to the feedback potential, wherein the microcontroller further monitors the product potential difference to obtain a maximum value of the product potential difference. A boost converter as claimed in claim 9, wherein the microcontroller determines whether to update and boost the product potential difference of the multiplier based on the average value of the rectified potential and the maximum value of the product potential difference.

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