TWI802319B - Constant on time converter control circuit and constant on time converter - Google Patents

Abstract

A constant on time converter control circuit and a constant on time converter are provided. The constant on time converter control circuit comprises an error amplifier, a voltage to current converter, and an initial current source. The error amplifier is for receiving a reference voltage signal and a feedback voltage signal and outputting a compensated voltage signal. The voltage to current converter receives the compensated voltage signal and outputs a converted current signal. The initial current source provides an initial current signal. The initial current signal and the converted current signal form a new reference voltage signal. A constant on time OFF time comparator receives the new reference voltage signal and the feedback voltage signal and outputs a control signal. The control signal affects the turning on and turning off of electronic switches to produce an output voltage of a constant on time converter.

Description

Constant on-time converter control circuit and constant on-time converter

The present application relates to a constant on-time converter, especially to an effectively controllable constant on-time converter control circuit to improve power supply voltage and load regulation.

Switching converters using constant on time (COT) circuits are often used in switch mode power supplies. However, it is difficult to stabilize the output voltage with a constant on-time (COT) control circuit.

A common disadvantage of constant on-time (COT) control circuits is that transient response errors negatively affect the supply voltage signal and load regulation signal.

Therefore, in order to overcome the shortcomings of the prior art, it is necessary to improve the constant on-time (COT) converter to efficiently and effectively achieve the power supply voltage and load regulation.

An object of the present application is to provide an effectively controllable constant on-time (COT) converter control circuit to improve power supply voltage and load regulation.

According to an embodiment of the present application, the present application provides a constant on-time (COT) converter control circuit, which includes an error amplifier, a voltage-to-current converter, and an initial current source.

The error amplifier is used for receiving a reference voltage signal and a feedback voltage signal and outputting a compensation voltage signal. The voltage-to-current converter is used for receiving the compensation voltage signal and outputting a converted current signal. The initial current source is used to provide an initial current, and the initial current and the converted current signal form a new reference voltage signal.

In some embodiments of the constant on-time converter control circuit, the constant on-time converter control circuit further includes a comparator for receiving the new reference voltage signal and the feedback voltage signal and outputting a control signal .

In some embodiments of the constant on-time converter control circuit, the control signal effects the opening and closing of a plurality of electronic switches to generate a constant on-time converter output voltage signal.

In some embodiments of the constant on-time converter control circuit, the comparator includes an off-time comparator.

In some embodiments of the constant on-time converter control circuit, the constant on-time converter control circuit further includes a summing resistor electrically connected to the initial current source.

In some embodiments of the constant on-time converter control circuit, the constant on-time converter control circuit further includes a low-pass filter electrically connected to an input terminal of the error amplifier.

In some embodiments of the constant on-time converter control circuit, the low pass filter includes a filter resistor and a filter capacitor.

In some embodiments of the constant on-time converter control circuit, the constant on-time converter control circuit further includes a compensation capacitor electrically connected to the output terminal of the error amplifier.

In some embodiments of the constant on-time converter control circuit, the constant on-time converter control circuit includes an error amplifier, a voltage-to-current converter, an initial current source, a constant on-time off-time comparator, a sum resistor, a low pass filter and a compensation capacitor. The error amplifier is used for receiving a reference voltage signal and a feedback voltage signal and outputting a compensation voltage signal. The voltage-to-current converter is used for receiving the compensation voltage signal and outputting a converted current signal. The initial current source is used to provide an initial current signal, and the initial current signal and the conversion current signal form a new reference voltage signal. The constant on-time off-time comparator is used to receive the new reference voltage signal and the feedback voltage signal and output a control signal, wherein the control signal affects the opening and closing of a plurality of electronic switches to generate a constant on-time converter output voltage signal. The sum resistor is electrically connected to the initial current source. The low-pass filter is electrically connected with an input end of the error amplifier. The compensation capacitor is electrically connected to the output terminal of the error amplifier.

According to an embodiment of the present application, the present application provides a constant on-time converter, which includes a constant on-time converter circuit and a constant on-time converter control circuit. The constant on-time converter circuit includes a comparator for receiving a new reference voltage signal and a feedback voltage signal and outputting a control signal, wherein the feedback voltage signal is provided internally by the constant on-time converter circuit . The constant on-time converter control circuit includes an error amplifier, a voltage-to-current converter and an initial current source. The error amplifier is used for receiving a reference voltage signal and the feedback voltage signal and outputting a compensation voltage signal. The voltage-to-current converter is used to receive the compensation voltage signal and output a switching current signal. The initial current source is used to provide an initial current signal, and the initial current signal and the conversion current signal form the new reference voltage signal.

In an embodiment of the present application, the initial current source provides the initial current signal, and the value of the initial current signal is obtained by multiplying the value of the reference voltage signal by a variable and dividing by the value of the sum resistor, wherein the The variable is a positive number less than 1.

In an embodiment of the present application, the variable is greater than 0.5.

100: Constant on-time converter

105: Comparator

110: Monostable multivibrator

115:Non-overlapping modules

120: level shifter

125: First buffer

130: Second buffer

135, 140: electronic switch

145: capacitance

150: Inductor

155: the first resistance

160: second resistance

165: the third resistor

170: load capacitance

175: load

180: Error Amplifier Controller

190: Turn on the time control circuit

210, 220, 230, 240: output voltage

310, 320: transient response

400, 400A: constant on-time converter control circuit

405: the third resistor

410: first resistance

415: second resistor

420: the fourth resistor

425: fifth resistor

430: the first capacitor

440: Error Amplifier

450:Voltage current converter

460: off-time comparator

470: second capacitor

475: The sixth resistor

480: Current source

490: Additional current source

600: Turn on the time control circuit

610: current source

615: the third capacitor

620: seventh resistance

625: Eighth resistor

630: ninth resistance

635: The fourth capacitor

640: Turn on the time comparator

LPF: Low Pass Filter

LX: node

PM: pulse width modulation

V _BG : Input voltage signal

V _DDP : input voltage signal

V _IN : input voltage

Vout: output voltage signal

V _REF : Reference voltage signal

V _FB : feedback voltage signal

V _SUM : Voltage

V _NREF : new reference voltage signal

FIG. 1 is a schematic diagram of a constant on-time (COT) converter with a control circuit according to an embodiment of the present application.

FIG. 2A is a schematic diagram of power voltage regulation of a constant on-time converter with a control circuit according to an embodiment of the present application and a constant on-time converter without the control circuit.

2B is a schematic diagram of load regulation of a constant on-time converter with a control circuit according to an embodiment of the present application and a constant on-time converter without the control circuit.

FIG. 3A is a schematic diagram of a transient response of a constant on-time converter without a control circuit according to an embodiment of the present application.

3B is a schematic diagram of the transient response of a constant on-time (COT) converter with an error amplifier controller according to an embodiment of the application.

FIG. 4 is a schematic diagram of a control circuit of a constant on-time (COT) converter according to an embodiment of the present application.

FIG. 5 is a schematic diagram of a control circuit of a constant on-time (COT) converter according to an embodiment of the present application.

FIG. 6 is a schematic diagram of a turn-on time control circuit of a constant on-time (COT) converter according to an embodiment of the present application.

FIG. 7A is a schematic waveform diagram of a transient response with a longer enabling time according to an embodiment of the present application.

FIG. 7B is a schematic waveform diagram of a transient response with a shorter enabling time according to an embodiment of the present application.

In order to facilitate the understanding of the purpose, features, and effects of the present application, the present application provides embodiments and drawings to describe the disclosed content of the present application in detail.

Please refer to FIG. 1 , which is a schematic diagram of a constant on-time (COT) converter 100 with a control circuit according to an embodiment of the present application.

As shown in FIG. 1 , the constant-on-time (COT) converter 100 includes a constant-on-time converter circuit (shown as a dotted line) and a constant-on-time converter control circuit (such as including an error amplifier controller 180), The constant on-time (COT) converter 100 is used to provide an output voltage signal V _out to a load (Load) 175 . The constant on-time converter control circuit is used as a control circuit, which provides a new reference signal according to a feedback voltage signal V _FB and a reference voltage signal V _BEF , wherein the feedback voltage signal V _FB is generated by the constant on-time converter circuit provided internally. For example, the constant on-time converter circuit includes a comparator 105, a monostable multivibrator (monostable multivibrator, MMV) 110, a non-overlapping module 115, a level shifter 120, a plurality of Electronic switches (eg 134, 140) and an output stage. The constant on-time converter control circuit includes an error amplifier controller 180 (shown as EA controller).

In one embodiment, the electronic switches 135 and 140 include N-type metal oxide half field effect transistors (MOSFETs). In another embodiment, the electronic switches 135 and 140 are other types of metal oxide semiconductor field effect transistors or other electronic switches.

The structure and architecture of the constant on-time (COT) converter 100 of the embodiment shown in FIG. 1 of the present application will be described in detail below.

As shown in FIG. 1 , the drain of the first electronic switch (Q _N1 ) 135 is electrically coupled to an input voltage V _IN . The source of the second electronic switch (Q _N2 ) 140 is grounded. The source of the first electronic switch 135 is connected to the drain of the second electronic switch 140 .

The output stage includes an inductor (L) 150, a first resistor (R ₁ ) 155, a second resistor (R ₂ ) 160, a third resistor (R _ESR ) 165, a load capacitor ( _CL ) 170 . A first end of the inductor 150 is connected to a node generated between the first electronic switch 135 and the second electronic switch 140 . The second terminal of the inductor 150 is connected to the first terminal of the first resistor 155 and the first terminal of the third resistor 165 , and provides the output voltage signal V _out to the load (Load) 175 . A second terminal of the first resistor 155 is connected to a first terminal of the second resistor 160 . The second terminal of the second resistor 160 is grounded. A second end of the third resistor 165 is connected to a first end of the load capacitor 170 . The second end of the load capacitor 170 is grounded.

The node formed by the connection between the first resistor 155 and the second resistor 160 is electrically connected to the negative input terminal of the comparator (cmp) 105 and provides a feedback voltage signal V _FB to the comparator 105 .

The feedback voltage signal V _FB is provided to the second input terminal of the error amplifier controller (EA controller) 180 . A reference voltage signal V _REF is provided to the first input terminal of the error amplifier controller 180 . The output terminal of the error amplifier controller 180 is electrically connected to the positive input terminal of the comparator 105 .

The output terminal of the comparator 105 is electrically connected to the input terminal of the monostable multivibrator (MMV) 110 and provides a pulse width modulation (PM) signal to the monostable multivibrator 110 .

輸出端，

輸出端為Q輸出端的反相。Q輸出端以及

輸出端皆與該非重疊模組115的兩個輸入端電性連接。 The monostable multivibrator 110 is, for example, an SR flip-flop having two input terminals, an R input terminal and an S input terminal. The output terminal of the comparator 105 can be connected with the S input terminal of the monostable multivibrator 110 . A turn-on time control circuit 190 can be connected to the R input terminal of the monostable multivibrator 110 . The monostable multivibrator 110 includes two output terminals, the Q output terminal and the

output terminal,

The output is the inverse of the Q output. Q output and

Both output terminals are electrically connected to two input terminals of the non-overlapping module 115 .

The first output terminal of the non-overlapping module 115 is connected to the input terminal of the level shifter 120 . The second output terminal of the non-overlapping module 115 is connected to the input terminal of a second buffer 130 . The output end of the second buffer 130 is electrically connected to the gate of the second electronic switch 140 .

An input voltage signal V _DDP is connected to the anode of a diode, and the cathode of the diode is connected to the first end of the level shifter 120 . A second terminal of the level shifter 120 is connected to a first terminal of the inductor (L) 150 . The output end of the level shifter 120 is electrically connected to the input end of a first buffer 125 . The first terminal of the first buffer 125 is electrically connected with the first terminal of the level shifter 120 and the cathode of the diode. The second terminal of the first buffer 125 is electrically connected with the first terminal of the inductor 150 and the second terminal of the level shifter 120 . The output end of the first buffer 125 is electrically connected to the gate of the first electronic switch 135 .

A capacitor (C _boot ) 145 is connected between the cathode of the diode and the first terminal of the inductor 150 .

By turning on and off the first electronic switch 135 and the second electronic switch 140, the electronic switches 135, 140 are controlled to convert the input voltage V _IN into the output voltage signal V _out .

The first electronic switch 135 is controlled to be turned on and off by the output signal of the level shifter 120 through the first buffer 125 . The second electronic switch is controlled to be turned on and off by the output signal output from the second output terminal of the non-overlapping module 115 by the second buffer 130 .

The output voltage signal V _out is converted into the feedback voltage signal V _FB , and the feedback voltage signal V _FB is provided to the negative input terminal of the comparator 105 and the second terminal of the error amplifier controller 180 . The error amplifier controller 180 utilizes the voltage level of the feedback voltage signal V _FB and the voltage level of the reference voltage signal V _REF and outputs a result to the positive input terminal of the comparator 105 . The comparator 105 compares the voltage level of the feedback voltage signal V _FB with the voltage level of the output signal from the error amplifier control circuit 180 and outputs a pulse width modulation (PWM) signal to the monostable multivibrator device 110.

The monostable multivibrator 110 receives a signal from the comparator 105 to generate a signal and a signal inverse to the signal, and provides the two signals to the non-overlapping module 115 .

Thereby, the first output signal from the non-overlapping module 115 controls the level shifter 120 to turn on and off the first electronic switch 135, and the second output signal from the non-overlapping module 115 turns on and off the second electronic switch 135. Two electronic switches 140 .

Please refer to FIG. 2A. FIG. 2A is a schematic diagram of the power supply voltage regulation rate of a constant on-time converter with a control circuit according to an embodiment of the present application and a constant on-time converter without the control circuit, wherein an output current is 10 The target output voltage signal V _out is set to 1.2 volts (V) in mA. Please refer to FIG. 2B. FIG. 2B is a schematic diagram of load regulation of a constant on-time converter with a control circuit according to an embodiment of the present application and a constant on-time converter without the control circuit, wherein an input voltage signal is 12 When volts (V), the target output voltage signal V _out is set to 5 volts (V). It should be reminded that FIG. 2A and FIG. 2B are simulation results of comparing a constant on-time converter with a control circuit (such as the constant on-time converter 100 shown in FIG. 1 ) with a constant on-time converter without a control circuit. . A constant on-time converter without a control circuit used in the simulation is, for example, a constant on-time converter comprising the constant on-time converter circuit of FIG. The reference voltage signal V _REF (eg, a constant voltage) is directly received without a control circuit.

As shown in FIG. 2A, without the control circuit (such as 180 in FIG. 1), when the input voltage (VIN) fluctuates, the output voltage (VOUT) (represented by 220) relative to the target input voltage And beyond the range (for example, between +0.5% and -0.5%) (as shown by the dotted line), thus resulting in poor supply voltage regulation. With the control circuit (eg, 180 in FIG. 1 ), the output voltage (VOUT) (represented by 210 ) remains stable and its supply voltage regulation is improved.

As shown in FIG. 2B, when the output current (IOUT) fluctuates, without the control circuit (180 in FIG. 1), the output voltage (VOUT) (represented by 240) varies with respect to the target output voltage In a range (eg between +4% and -5.5%) (as shown by the dashed line) it drops, thus resulting in poor load regulation. With the control circuit (eg, 180 in FIG. 1 ), the output voltage (VOUT) (indicated by 230 ) remains stable and its load regulation is improved.

Please refer to FIG. 3A. FIG. 3A is a schematic diagram of the transient response of a constant on-time converter without a control circuit according to an embodiment of the present application. Please refer to FIG. 3B. FIG. 3B is a schematic diagram of a control circuit with an error amplifier according to an embodiment of the present application. Schematic diagram of the transient response of the constant on-time converter of the controller.

As shown in FIG. 3B , the output voltage in the transient response of the constant on-time converter with the control circuit (such as 180 in FIG. 1 ) is compared to the constant on-time converter without the control circuit shown in FIG. 3A . The transient response (310) of the converter may have an undershoot waveform or a drop glitch waveform (320).

Therefore, in order to improve the increased transient response of the control circuit (eg, 180 in FIG. 1 ), an embodiment of the control circuit of the constant on-time converter is proposed according to the present application to generate the new reference voltage signal V _NREF as follows.

Please refer to FIG. 4 . FIG. 4 is a schematic diagram of a control circuit of a constant on-time (COT) converter (or called a constant on-time converter control circuit) according to an embodiment of the present application.

As shown in FIG. 4 , the constant on-time converter control circuit 400 for generating a new reference voltage signal V _NREF includes an error amplifier 440 (or an error amplifier stage) and a voltage-to-current converter 450 .

The error amplifier 440 is used for receiving a reference voltage signal V _REF and a feedback voltage signal V _FB and outputting a compensation voltage signal.

For example, the feedback voltage signal V _FB can be provided by a voltage divider. An input voltage signal V _BG is provided to a first end of a third resistor (R ₃ ) 405 . A second end of the third resistor 405 is electrically connected to a first end of a first resistor (R _TRIM1 ) 410 . The second terminal of the first resistor 410 is electrically connected to the first terminal of a second resistor (R _TRIM2 ) 415 . A second terminal of the second resistor 415 is electrically connected to a first terminal of a fourth resistor (R ₄ ) 420 . The node generated by the connection between the first resistor 410 and the second resistor 415 is electrically connected to a first end of a fifth resistor (R ₅ ) 425 to provide the reference voltage signal V _REF .

In the error amplifier stage (shown by the dotted line), the second terminal of the fifth resistor 425 is connected to the first terminal of the error amplifier 440 . A first capacitor (C ₁ ) 430 is connected between the first input terminal of the error amplifier 440 and a reference ground. The feedback voltage signal V _FB is provided to the second input terminal of the error amplifier 440 . The feedback voltage signal V _FB is internally provided by the constant on-time converter circuit (as shown by the dotted line in FIG. 1 ).

The output terminal of the error amplifier 440 is electrically connected to the input terminal of the voltage-current converter 450 (eg, an active voltage-current converter based on an operational amplifier). A second capacitor ( C2 ) 470 is connected between the output terminal of the error amplifier 440 and the ground terminal. The output of the voltage-to-current converter 450 provides a current source 480 to generate a voltage V _SUM as the new reference voltage signal V _NREF . The new reference voltage signal V _NREF is provided to a second input terminal of an off-time comparator 460 . A sixth resistor (R ₆ ) 475 is connected to the second input terminal of the off-time comparator 460 . The feedback voltage signal V _FB is provided to a first input terminal of the off-time comparator 460 .

In operation, the error amplifier 440, the fifth resistor 425 and the first capacitor 430 (or the error amplifier stage) work together to provide DC calibration. The second capacitor 470 provides a compensation function.

Please refer to FIG. 4 and FIG. 1 , according to an embodiment of the present application, the output of the constant on-time converter control circuit 400 in FIG. 4 is the new reference voltage signal V _NREF , and the new reference voltage signal V _NREF is used to input to The positive input of the comparator 105 of FIG. 1 .

In the embodiment of the present application, the off-time comparator 460 in FIG. 4 is used as an implementation of the comparator 105 in FIG. 1 .

Please refer to FIG. 5 , which is a schematic diagram of a control circuit of a constant on-time (COT) converter according to an embodiment of the present application.

In the embodiment of the present application shown in FIG. 5 , compared with FIG. 4 , a constant on-time converter control circuit 400A further includes an additional current source 490, which provides an initial current Iinit to the turn-off The second input terminal of the time comparator 460 provides the voltage V _SUM as the new reference voltage signal V _NREF . The new reference voltage signal V _NREF is determined based on the current source 480 and the current source 490 . In some embodiments, the current source 490 can be implemented with one or more current sources.

For example, the formula of the initial current is Iinit*R ₆ =variable*V _REF , wherein R ₆ represents the resistance value of the sixth resistor 475 in FIG. 5 , and V _REF represents the resistance provided to the first end of the fifth resistor 425 The reference voltage signal. In other words, the current value of the initial current signal can be determined by multiplying the reference voltage signal by a variable and dividing by the resistance value of the summing resistor. The variable is, for example, a weight value selected according to circuit requirements. When the variable is larger, the switching speed will be faster or the transient response will be better. For example, this variable may be chosen to be 0.9 to obtain a 90% V _REF result. In some embodiments, this variable can be a positive number less than 1, such as 0.5, 0.6, 0.7, 0.8, 0.91, 0.95, to obtain proportional V _REF results. During the operation of the constant on-time converter control circuit, the initial current Iinit is always enabled and disabled.

In the embodiment of FIG. 5 , compared with FIG. 4 , since the current source 490 provides the initial current Iinit, the error amplifier 440 provides the load of the current source 480 through the voltage-to-current converter 450 to reduce or be determined by the current source 490. current source 490 to share. Therefore, the transient response of the constant-on-time converter using the constant-on-time converter control circuit 400A can be improved.

Please refer to FIG. 6 , which is a schematic diagram of a turn-on time control circuit 600 of a constant on-time (COT) converter according to an embodiment of the present application. Please refer to FIG. 6 and FIG. 1. In an embodiment of the present application, the turn-on time control circuit 600 in FIG. 6 is an implementation of the turn-on time control circuit 190 in FIG. The terminal is coupled to the R input terminal of the monostable multivibrator 110 in FIG. 1 .

The turn-on time control circuit 600 includes a current source 610, which provides a signal to a second input terminal of a turn-on time comparator 640, wherein the current of the current source 610 is implemented to be consistent with the constant on-time (COT) The input voltage V _IN of converter 100 is proportional. Therefore, the turn-on time will decrease as the signal increases.

A first terminal of a seventh resistor (R ₇ ) 620 is connected to the output stage, such as node LX connected to the inductor 150 . A second terminal of the seventh resistor (R ₇ ) 620 is connected to a first terminal of an eighth resistor (R ₈ ) 625 . The second end of the eighth resistor 625 is connected to the reference ground. A first end of a ninth resistor (R ₉ ) 630 is connected to a node generated between the seventh resistor 620 and the eighth resistor 625 . A second terminal of the ninth resistor 630 is connected to a first input terminal of the on-time comparator 640 .

A third capacitor (C ₃ ) 615 is connected between the current source 610 and the reference ground. A fourth capacitor (C ₄ ) 635 is connected between the second end of the ninth resistor 630 and the reference ground. The ninth resistor 630 and the fourth capacitor 635 together form a low-pass filter LPF. The signal output from the low-pass filter LPF to the first input terminal of the on-time comparator 640 is approximately equal to the output voltage signal V _out .

Please refer to FIG. 7A. FIG. 7A is a waveform diagram of a transient response with a longer enabling time according to an embodiment of the present application. Please refer to FIG. 7B. FIG. 7B is a waveform diagram of a transient response with a shorter enabling time according to an embodiment of the present application The waveform diagram of the transient response of energy time.

As shown in FIG. 7A , a transient response of a circuit with a longer enable time will result in a falling spike (or undershoot) during the transition. As shown in FIG. 7B , the transient response of the circuit with a shorter enable time does not show a drop spike at the time of transition.

In the embodiments described above, the embodiment of the constant on-time (COT) converter 100 is for illustration only. Certainly, the constant on-time converter with the converter control circuit (as shown in FIG. 5 ) of the present application can be based on the constant on-time converter circuit of FIG. , step-down converter) to achieve.

Although the content disclosed in this application has been described with the help of specific embodiments, those skilled in the art may make many modifications and changes to it without departing from the content disclosed in this application described in the patent scope of the application. scope and spirit.

100: Constant on-time converter

105: Comparator

110: Monostable multivibrator

115:Non-overlapping modules

120: level shifter

125: First buffer

130: Second buffer

135, 140: electronic switch

145: capacitance

150: Inductor

155: the first resistance

160: second resistance

165: the third resistor

170: load capacitance

175: load

180: Error Amplifier Controller

190: Turn on the time control circuit

LX: node

PM: pulse width modulation

V _DDP : input voltage signal

V _IN : input voltage

Vout: output voltage signal

V _REF : Reference voltage signal

V _FB : feedback voltage signal

Claims (20)

A constant on-time converter control circuit, which includes: an error amplifier, used to receive a reference voltage signal and a feedback voltage signal and output a compensation voltage signal; a voltage-to-current converter, used to receive the compensation voltage signal and output Outputting a switching current signal; and an initial current source for providing an initial current signal, the initial current signal and the switching current signal form a new reference voltage signal. The constant on-time converter control circuit as described in Claim 1 further includes: a comparator for receiving the new reference voltage signal and the feedback voltage signal and outputting a control signal. The constant on-time converter control circuit as claimed in claim 2, wherein the control signal affects the opening and closing of a plurality of electronic switches to generate an output voltage signal of the constant on-time converter. The constant on-time converter control circuit as claimed in claim 2, wherein the comparator includes an off-time comparator. The constant on-time converter control circuit as claimed in claim 1, further comprising: a summing resistor electrically connected to the initial current source. The constant-on-time converter control circuit as claimed in claim 1, further comprising: a low-pass filter electrically connected to an input terminal of the error amplifier. The constant on-time converter control circuit as claimed in claim 6, wherein the low-pass filter includes a filter resistor and a filter capacitor. The constant on-time converter control circuit as claimed in claim 1 further includes: a compensation capacitor electrically connected to the output terminal of the error amplifier. The constant on-time converter control circuit as described in Claim 5, wherein the initial current source provides the initial current signal, and the value of the initial current signal is based on the value of the reference voltage signal multiplied by a variable and divided by the sum resistance , where the variable is a positive number less than 1. The constant on-time converter control circuit as claimed in claim 9, wherein the variable is greater than 0.5. A constant on-time converter control circuit, which includes: an error amplifier, used to receive a reference voltage signal and a feedback voltage signal and output a compensation voltage signal; a voltage-to-current converter, used to receive the compensation voltage signal and output Outputting a converted current signal; an initial current source, used to provide an initial current signal, the initial current signal and the converted current signal form a new reference voltage signal; a constant on-time off-time comparator, used to receive the new The reference voltage signal and the feedback voltage signal and output a control signal; wherein the control signal affects the opening and closing of a plurality of electronic switches to generate an output voltage signal of a constant on-time converter; a summation resistor, and the initial current source electrically connected; a low-pass filter electrically connected to an input end of the error amplifier; and a compensation capacitor electrically connected to an output end of the error amplifier. The constant on-time converter control circuit as described in claim 11, wherein the initial current source provides the initial current signal, and the value of the initial current signal is based on the value of the reference voltage signal multiplied by a variable and divided by the sum resistance , where the variable is a positive number less than 1. The constant on-time converter control circuit as claimed in claim 12, wherein the variable is greater than 0.5. A constant on-time converter, which includes: a constant on-time converter circuit, which includes a comparator, the comparator is used to receive a new reference voltage signal and a feedback voltage signal and output a control signal, wherein the feedback The voltage signal is provided internally by the constant on-time converter circuit; and a constant on-time converter control circuit, which includes: an error amplifier for receiving a reference voltage signal and the feedback voltage signal and outputting a compensation voltage signal; A voltage-to-current converter is used to receive the compensation voltage signal and output a converted current signal; and an initial current source is used to provide an initial current signal, and the initial current signal and the converted current signal form the new reference voltage signal. The constant on-time converter as claimed in claim 14, wherein the control signal affects the opening and closing of a plurality of electronic switches to generate the output voltage signal of the constant on-time converter. The constant on-time converter as claimed in claim 14, wherein the comparator comprises an off-time comparator. The constant on-time converter as claimed in claim 14, wherein the constant on-time converter control circuit further includes: a summing resistor electrically connected to the initial current source. The constant-on-time converter as claimed in claim 14, wherein the constant-on-time converter control circuit further includes: a low-pass filter electrically connected to an input terminal of the error amplifier. The constant on-time converter as claimed in claim 14, wherein the constant on-time converter control circuit further includes: a compensation capacitor electrically connected to the output terminal of the error amplifier. The constant on-time converter as claimed in claim 17, wherein the initial current source provides the initial current signal, the value of the initial current signal is based on the value of the reference voltage signal multiplied by a variable and divided by the value of the summing resistance , where the variable is a positive number less than 1.

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