TW201328160A - Voltage generator and voltage generating method with wide dynamic range - Google Patents

Abstract

A voltage generator and a voltage generating method with wide dynamic range are provided. The voltage generator includes a transformer, a switching-transistor circuit, a rectification circuit, an adjustable voltage-divider circuit and a feedback circuit. The switching-transistor circuit switches a primary winding voltage of the transformer by using a source voltage according to a modulation signal. Input of the rectification circuit is coupled to a secondary winding of the transformer. Output of the rectification circuit provides a target voltage. Input of the adjustable voltage-divider circuit is coupled to output of the rectification circuit. Output of the adjustable voltage-divider circuit provides a feedback voltage. Dividing ratio of the adjustable voltage-divider circuit is controlled by a control signal. Input of the feedback circuit is coupled to output of the adjustable voltage-divider circuit. The feedback circuit compares the feedback voltage and a reference voltage, and adjusts the modulation signal according to the compare result.

Description

Large dynamic range voltage generator and voltage generation method

The present disclosure relates to a voltage generator, and more particularly to a high dynamic range high voltage generator.

Conventional DC-to-DC voltage conversion circuits can convert different voltage levels into fixed output voltages. However, for some applications where the DC output voltage needs to be linearly converted with the input voltage level, such as the voltage generator of the electrostatic test system, the conventional DC-to-DC voltage conversion circuit cannot provide the high voltage of this large dynamic range. Taking an electrostatic test system as an example, the voltage output range of the voltage generator must meet a continuously adjustable voltage of a minimum DC voltage of 80 volts to a maximum voltage of 8000 volts. Traditional voltage generators cannot provide this large dynamic range of voltage.

The traditional voltage generator is mainly used for the conversion of the fixed output voltage, so the voltage adjustment at the output end can be met within ten times. For example, a buck converter with an input voltage of 24 volts and an output voltage fixed at 5 volts has a duty ratio of the internal pulse width modulation signal designed to be in the range of 10% to 80%. However, for some applications that require a large dynamic range (output voltage adjustment range needs to be more than 100 times, such as a minimum output voltage of about 80 volts, and the maximum output voltage must be 8000 volts), pulse width modulation using a conventional voltage generator The way has not been able to meet this need.

The present disclosure provides a large dynamic range voltage generator and voltage generation method, which uses pulse width modulation technology and amplitude modulation technology to increase the output voltage adjustable range to meet the requirements of a large dynamic range.

The disclosed embodiment proposes a large dynamic range voltage generator, including a transformer, a switching crystal circuit, a rectifier circuit, an adjustable voltage dividing circuit, and a feedback circuit. The transformer has at least a primary winding and a secondary winding. The switching crystal circuit is coupled to the primary side coil of the transformer. The switching crystal circuit drives the primary side coil using the source voltage according to the modulation signal. The input end of the rectifier circuit is coupled to the secondary side coil of the transformer. The output of the rectifier circuit provides the target voltage as the output of the voltage generator. The input end of the adjustable voltage dividing circuit is coupled to the output end of the rectifier circuit. The output of the adjustable voltage dividing circuit provides a feedback voltage, wherein the voltage dividing ratio of the adjustable voltage dividing circuit is controlled by the first control signal. The input end of the feedback circuit is coupled to the output of the adjustable voltage dividing circuit. The output end of the feedback circuit provides a modulation signal to the switching crystal circuit, wherein the feedback circuit compares the feedback voltage with the reference voltage, and adjusts the modulation signal according to the comparison result.

The disclosed embodiment proposes a large dynamic range voltage generating method. The voltage generating method includes: providing a transformer having at least a primary side coil and a secondary side coil; providing a switching crystal circuit coupled to the primary side coil of the transformer; The modulation signal uses a source voltage to drive the primary side coil; a rectifier circuit is provided, the input end of the rectifier circuit is coupled to the secondary side coil of the transformer; and a target voltage is provided as the voltage from the output end of the rectifier circuit An output of the generator; an adjustable voltage dividing circuit is provided, the input end of the adjustable voltage dividing circuit is coupled to the output end of the rectifier circuit; and a feedback voltage is provided by the output end of the adjustable voltage dividing circuit The voltage dividing ratio of the adjustable voltage dividing circuit is controlled by a first control signal; a feedback circuit is provided, and an input end of the feedback circuit is coupled to an output end of the adjustable voltage dividing circuit; The feedback circuit compares the feedback voltage with a reference voltage, and adjusts the modulation signal according to the comparison result to provide the modulation signal to the switching crystal circuit; providing an adjustable voltage source, The output terminal of the voltage source is coupled to the switching circuit crystal; and adjusting the source voltage in accordance with a second control signal generated by the adjustable voltage source to provide the voltage to the source of the switching transistor circuit.

The disclosed embodiment proposes a large dynamic range voltage generator including a transformer, a switching crystal circuit, an adjustable voltage source, a rectifier circuit, and a feedback circuit. The transformer has at least a primary side coil and a secondary side coil. The switching crystal circuit is coupled to the primary side coil of the transformer. The switching crystal circuit drives the primary side coil using the source voltage according to the modulation signal. An output of the adjustable voltage source is coupled to the switching crystal circuit to provide the source voltage, wherein the adjustable voltage source adjusts the source voltage in accordance with the control signal. The input end of the rectifier circuit is coupled to the secondary side coil of the transformer. The output of the rectifier circuit provides the target voltage as the output of the voltage generator. The input end of the feedback circuit is coupled to the output of the rectifier circuit. The output of the feedback circuit provides a modulated signal to the switching crystal circuit, wherein the feedback circuit adjusts the modulated signal according to the target voltage.

The disclosed embodiment proposes a large dynamic range voltage generating method. The voltage generating method includes: providing a transformer having at least a primary side coil and a secondary side coil; providing a switching crystal circuit coupled to the primary side coil of the transformer; The modulated signal uses a source voltage to drive the primary side coil; an adjustable voltage source is provided, the output end of the adjustable voltage source is coupled to the switching crystal circuit; and the adjustable voltage source adjusts the source voltage according to a control signal Providing the source voltage to the switching crystal circuit; providing a rectifying circuit, the input end of the rectifying circuit is coupled to the secondary side coil of the transformer; and a target voltage is provided by the output end of the rectifying circuit as the voltage generating An output of the feedback circuit, the input end of the feedback circuit is coupled to the output end of the rectifier circuit; and the modulated signal is supplied from the output of the feedback circuit to the switching crystal circuit, wherein the feedback circuit The circuit adjusts the modulation signal according to the target voltage.

Based on the above, the disclosed embodiment improves the dynamic range of the target voltage by adjusting the voltage division ratio of the voltage dividing circuit and/or adjusting the voltage amplitude of the voltage source.

The above described features and advantages of the present invention will be more apparent from the following description.

FIG. 1 is a functional block diagram illustrating a large dynamic range voltage generator 100 in accordance with an embodiment of the present disclosure. The voltage generator 100 includes a switching crystal circuit 110, a transformer 120, a rectifier circuit 130, an adjustable voltage dividing circuit 140, and a feedback circuit 150. The switching crystal circuit 110 is coupled to a primary winding 121 of the transformer 120. According to the control of the modulation signal Sm, the switching crystal circuit 110 drives the primary side coil 121 using the source voltage Vs. The input of the rectifier circuit 130 is coupled to a secondary winding 122 of the transformer 120. The output of the rectifier circuit 130 provides the target voltage Vout as the output of the voltage generator 100. In some embodiments, the rectifier circuit 130 can rectify and/or double the output of the secondary side coil 122 of the transformer 120 to provide a target voltage Vout.

The input end of the adjustable voltage dividing circuit 140 is coupled to the output end of the rectifier circuit 130. The output of the adjustable voltage dividing circuit 140 provides a feedback voltage Vfb. Wherein, the voltage dividing ratio of the adjustable voltage dividing circuit 140 is controlled by the first control signal Sc1. For example, according to the control of the first control signal Sc1, the resistance ratio of Ru:Rd of the upper and lower resistors of the adjustable voltage dividing circuit 140 can be adjusted to 1000:1, 500:1, 125:1 or other ratio. The input end of the feedback circuit 150 is coupled to the output of the adjustable voltage dividing circuit 140. The output of the feedback circuit 150 provides a modulated signal Sm to the switching crystal circuit 110. The feedback circuit 150 compares the feedback voltage Vfb with the reference voltage Vref, and adjusts the modulation signal Sm according to the comparison result.

The switching crystal circuit 110 may be a flyback power conversion circuit, a push-pull power conversion circuit, a forward power conversion circuit, a half-bridge power conversion circuit, Full-bridge power conversion circuit or other type of switching circuit. The switching crystal circuit 110 converts the DC source voltage Vs into an AC signal in a high frequency switching manner. It is assumed that the amplitude of the AC signal is Vp, and the turns ratio of the transformer 120 is Ns: Np. After the AC signal enters the primary side coil 121 of the transformer 120, it is converted into an AC signal having a maximum amplitude of Ns × Vp / Np and outputted from the secondary side coil 122. The AC signal of the secondary side coil 122 is rectified and/or doubled by the rectifier circuit 130, and then the required DC target voltage Vout is output.

In order to maintain the stability of the output target voltage Vout, the adjustable voltage dividing circuit 140 may sample the target voltage Vout according to the first control signal Sc1, and return the sampling result (the feedback voltage Vfb) to the feedback circuit 150. The feedback circuit 150 compares the feedback voltage Vfb with the reference voltage Vref and adjusts the modulation signal Sm according to the comparison result. The modulation signal Sm controls the on and off times of the switches inside the switching crystal circuit 110. Thus, the voltage generator 100 can maintain the stability of the output target voltage Vout. In the embodiment, the voltage generator 100 can output the dynamic range of the target voltage Vout by changing the first control signal Sc1.

FIG. 2 is a schematic diagram showing an example circuit of the voltage generator 100 shown in FIG. 1. The embodiment shown in FIG. 2 can refer to the related description of FIG. 1. Referring to FIG. 2, the present embodiment implements the voltage generator 100 with a flyback architecture. The switching crystal circuit 110 includes a wire 111 and a switching crystal 112. The first end of the wire 111 receives the source voltage Vs. The second end of the wire 111 is coupled to the first end of the primary side coil 121 of the transformer 120. The first end of the switching crystal 112 is coupled to the second end of the primary side coil 121 of the transformer 120. The second end of the switching crystal 112 is grounded. The control terminal of the switching crystal 112 is coupled to the feedback circuit 150 to receive the modulation signal Sm. The modulation signal Sm quickly turns on/off the switching crystal 112 so that the DC source voltage Vs can be converted into an AC signal. The amount of energy of the alternating current signal of the primary side coil 121 is modulated correspondingly by changing the modulation signal Sm.

According to the turns ratio Ns:Np of the transformer 120, the transformer 120 can convert an AC signal having a maximum amplitude of Vp in the primary side coil 121 into an AC signal having a maximum amplitude of Ns × Vp/Np in the secondary side coil 122. The anode of the diode D1 of the rectifier circuit 130 is coupled to the first end of the secondary side coil 122 of the transformer 120. The cathode of the diode D1 serves as an output terminal of the rectifier circuit 130. Therefore, the rectifying circuit 130 rectifies the alternating current signal of the secondary side coil 122 and outputs the required direct current voltage Vout. The first end of the capacitor C1 of the rectifier circuit 130 is coupled to the cathode of the diode D1. The second end of the capacitor C1 is coupled to the second end of the secondary side coil 122 of the transformer 120. The capacitor C1 can filter the AC noise of the voltage Vout and improve the stability of the target voltage Vout.

In this embodiment, the first control signal Sc1 includes a first switch signal S1, a second switch signal S2, and a third switch signal S2. The adjustable voltage dividing circuit 140 includes an upper resistor Ru, a first switch 141, a second switch 142, a third switch 143, a first lower resistor Rd1, a second lower resistor Rd2, and a third lower resistor Rd3. The first end of the upper resistor Ru is coupled to the output of the rectifier circuit 130. The second end of the upper resistor Ru serves as an output of the adjustable voltage dividing circuit 140. The first end of the first switch 141, the second switch 142 and the third switch 143 are coupled to the second end of the upper resistor Ru. The control end of the first switch 141 receives the first switch signal S1, and the second end of the first switch 141 is coupled to the first end of the first lower resistor Rd1. The control terminal of the second switch 142 receives the second switch signal S2, and the second end of the second switch 142 is coupled to the first end of the second lower resistor Rd2. The control end of the third switch 143 receives the third switch signal S3, and the second end of the third switch 143 is coupled to the first end of the third lower resistor Rd3. The second ends of the first lower resistor Rd1, the second lower resistor Rd2, and the third lower resistor Rd3 are coupled to the second end of the secondary side coil 122 of the transformer 120. The resistance values of the first lower resistor Rd1, the second lower resistor Rd2, and the third lower resistor Rd3 are different from each other.

By determining the conduction states of the first switch 141, the second switch 142, and the third switch 143, the resistance ratio of the upper and lower resistances of the adjustable voltage dividing circuit 140 can be changed, such as 1000:1, 500. : 1, 125:1 or other ratio. Although the lower resistor Rd in FIG. 2 shows three sets of lower resistors Rd1, Rd2 and Rd3, and the upper resistor Ru only shows a set of upper resistors, the implementation of the adjustable voltage dividing circuit 140 is not limited thereto. For example, the lower resistor Rd may be composed of two sets of lower resistors Rd1, Rd2 and switches 141, 142, or four or more sets of lower resistors and switches. Similarly, the upper resistor Ru can be composed of multiple sets of upper resistors and switches. Therefore, the first control signal Sc1 can change the resistance ratio of the upper and lower resistances of the adjustable voltage dividing circuit 140 to Ru: Rd to any ratio.

In the present embodiment, the feedback circuit 150 includes an error amplifier 151 and a pulse width modulation (PWM) module 152. The first input end of the error amplifier 151 is coupled to the output of the adjustable voltage dividing circuit 140 to receive the feedback voltage Vfb. The second input of the error amplifier 151 is coupled to the reference voltage Vref. The input end of the pulse width modulation module 152 is coupled to the output of the error amplifier 151. The output of the pulse width modulation module 152 is coupled to the switching crystal circuit 110 to provide a modulation signal Sm. The pulse width modulation module 152 adjusts the pulse width of the modulation signal Sm according to the output of the error amplifier 151.

By determining the conduction states of the first switch 141, the second switch 142, and the third switch 143, the resistance ratio of the upper and lower resistances of the adjustable voltage dividing circuit 140 can be changed, such as 1000:1, 500. :1 or 125:1. The feedback voltage Vfb of the adjustable voltage dividing circuit 140 is sent from the error amplifier 151 to the pulse width modulation module 152. According to the error magnitude of the feedback voltage Vfb and the reference voltage Vref, the pulse width modulation module 152 controls the switching transistor 112 to be turned on and off, so that the stability of the output target voltage Vout can be maintained. According to the architecture of the embodiment, the target voltage Vout can be set via the first control signal Sc1, and the dynamic range of the output target voltage Vout can be adjusted by a hundred times.

The embodiment shown in FIG. 2 also includes an adjustable voltage source 410. Referring to FIG. 2, the output of the adjustable voltage source 410 is coupled to the switching crystal circuit 110 to provide a source voltage Vs. The adjustable voltage source 410 adjusts the source voltage Vs according to the second control signal Sc2. In this embodiment, the second control signal Sc2 includes switching signals S4, S5, and S6. The adjustable voltage source 410 includes switches 411, 412, and 413. The first end of the switch 411 receives the first DC voltage VDC1. The control terminal of the switch 411 receives the switch signal S1. The first end of the switch 412 receives the second DC voltage VDC2. The control terminal of switch 412 receives switch signal S2. The first end of the switch 413 receives the third DC voltage VDC3. The control terminal of the switch 413 receives the switch signal S3. The second ends of the switches 411, 412, and 413 are coupled to the output of the adjustable voltage source 410. The first DC voltage VDC1, the second DC voltage VDC2, and the third DC voltage VDC3 are different from each other. For example, the first DC voltage VDC1 is 2 V, the second DC voltage VDC2 is 8 V, and the third DC voltage VDC3 is 16 V.

In this embodiment, a plurality of analog switches are added to the primary side 121 of the transformer 120 to select and change the amplitude of the AC voltage entering the primary side 121 of the transformer 120. In this embodiment, the adjustable voltage dividing circuit 140 is simultaneously added to the feedback path of the output target voltage Vout to select and change the sampling range of the feedback voltage Vfb. Referring to FIG. 2, the conduction states of the switches 411, 412, and 413 can be controlled by the switch signals S4, S5, and S6, and then the DC voltages VDC1, VDC2, or VDC3 are selected to enter the primary side 121 of the transformer 120. The switching crystal circuit 110 drives the primary side coil 121 in accordance with the source voltage Vs and the modulation signal Sm.

It is assumed that when the adjustable voltage source 410 selects the DC voltage VDC1, VDC2 or VDC3, the maximum amplitude of the AC signal outputted by the switching crystal circuit 110 to the primary side coil 121 is Vp1, Vp2 or Vp3, respectively. Depending on the turns ratio of the transformer 120 (for example, Ns: Np), the maximum amplitude of the alternating current signal of the secondary side coil 122 is Ns × Vp1/Np or Ns × Vp2 / Np or Ns × Vp3 / Np. This AC signal is rectified/doubled by the rectifying circuit 130 to output a desired DC target voltage Vout. In order to maintain the stability of the target voltage Vout, the target voltage Vout selects the voltage dividing resistor as Rd1, Rd2 or Rd3 via a plurality of control switches 141, 142 or 143 depending on the output voltage range. The adjustable voltage dividing circuit 140 samples the target voltage Vout and outputs a feedback voltage Vfb to the input of the error amplifier 151. Based on the magnitude of the error output by the error amplifier 151, the pulse width modulation module 152 controls the turn-on and turn-off times of the switching crystal 112. As such, the voltage generator 400 can maintain the stability of the output voltage. Through the structure of this embodiment, the voltage generator 400 can set the target voltage Vout via the adjustment of the control signal Sc1, the control signal Sc2, and/or the reference voltage Vref, and the dynamic range of the target voltage Vout can be adjusted by a hundred times.

The design method of the voltage generator 400 in FIG. 2 can be referred to the following description. First, it is decided to switch the topology type of the crystal circuit 110, such as a flyback, push-pull, forward, half-bridge, full-bridge or other topology type. The conversion functions for various topology types are as follows:

Flyback:

Forward type:

Push-pull:

Half bridge type:

Full bridge type:

The above n represents the voltage doubler ratio of the rectifier circuit 130, Ns represents the number of turns of the transformer secondary side 122, Np represents the number of turns of the transformer primary side 121, and D represents the conductance or duty ratio of the modulated signal Sm. The above V _{OUT_OL} indicates the output target voltage Vout of the voltage generator 400 under the condition of the open circuit, that is, the condition that the connection between the adjustable voltage dividing circuit 140 and the rectifier circuit 130 is temporarily cut off.

It is assumed that the push-pull topology type is selected to implement the switching crystal circuit 110. It is also assumed that the voltage doubler ratio n of the rectifier circuit 130 is 2, and the turns ratio Ns:Np of the transformer 120 is 100:1. Under the condition of the open circuit, the relationship between the duty cycle D of the modulation signal Sm and the output V _{OUT_OL} of the voltage generator 400 is calculated in Table 1, Table 2 and Table 3. When the source voltage Vs output from the adjustable voltage source 410 is 2 V, the relationship between the duty cycle D of the modulation signal Sm and the output V _{OUT_OL} of the voltage generator 400 is as shown in Table 1. When the source voltage Vs output from the adjustable voltage source 410 is 8 V, the relationship between the duty cycle D of the modulation signal Sm and the output V _{OUT_OL} of the voltage generator 400 is as shown in Table 2. When the source voltage Vs output from the adjustable voltage source 410 is 16 V, the relationship between the duty cycle D of the modulation signal Sm and the output V _{OUT_OL} of the voltage generator 400 is as shown in Table 3.

It can be verified from the calculation results of Table 1, Table 2 and Table 3. Under the open circuit, if the DC voltage VDC1 is 2 V, the dynamic range of the output V _{OUT_OL} of the voltage generator 400 is 80 V to 720 V. If the DC voltage VDC2 is 8 V, the dynamic range of the output V _{OUT_OL} of the voltage generator 400 is 320 V to 2880 V. If the DC voltage VDC3 is 16 V, the dynamic range of the output V _{OUT_OL} of the voltage generator 400 is 640 V to 5760 V. These three output dynamic ranges partially overlap each other.

Next, the closed loop output voltage values are each selected for each of the above three output dynamic ranges. The dynamic range of the closed loop output voltage value needs to be a subset of the dynamic range of the open loop output voltage value. According to the design requirements of the actual product, for example, for the dynamic range of the above-mentioned open loop output voltage V _{OUT_OL} of 80 V to 720 V, the lower limit of the dynamic range of the closed loop output target voltage value Vout ₍ Vout _(MIN) and the upper limit Vout _(MAX) are respectively selected. It is 87.5 V and 625 V, as shown in Table 4. By analogy, for the dynamic range of the open loop output voltage V _{OUT_OL} of 320 V to 2880 V, the lower limit Vout _(MIN) and the upper limit Vout _(MAX) are selected to be 350 V and 2500 V, respectively. _For the dynamic range of the above open loop output voltage V _{OUT_OL} 320 V to 2880 V, the lower limit Vout _(MIN) and the upper limit Vout _(MAX) are selected to be 700 V and 5000 V, respectively.

Next, according to the lower limit Vout _(MIN) and the upper limit Vout _(MAX) of the dynamic range of the closed loop output voltage value of each group, the resistance ratio of the upper and lower resistances of the adjustable voltage dividing circuit 140 is set to Ru: Rd. The calculation equation for the voltage divider circuit is:

Vout=Vref×(Ru+Rd)/Rd

The calculation results of the above equations are shown in Tables 5, 6, and 7. Table 5 shows that when the adjustment range of the reference voltage Vref is about 0.7~5 V, if the target voltage value Vout dynamic range is 87.5~625 V, the resistance of the upper resistor Ru is 1M Ω, and the resistance of the lower resistor Rd is The value is 8K Ω. Table 6 shows that when the adjustment range of the reference voltage Vref is about 0.7~5 V, if the target voltage value Vout dynamic range is 350~2500 V, the resistance of the upper resistor Ru is 1M Ω, and the resistance of the lower resistor Rd is The value is 2K Ω. Table 7 shows that when the adjustment range of the reference voltage Vref is about 0.7~5 V, if the target voltage value Vout dynamic range is 700~5000 V, the resistance of the upper resistor Ru is 1M Ω, and the resistance of the lower resistor Rd is The value is 1K Ω.

Table 6

Through the above design method, the voltage levels of the DC voltages VDC1, VDC2, and VDC3 in the voltage generator 400 can be determined, and the resistance ratio of the upper and lower resistances of the adjustable voltage dividing circuit 140 to Ru: Rd can also be determined.

The implementation of the rectifier circuit 130 shown in FIG. 2 is merely an example. In other embodiments, the rectifier circuit 130 can be implemented in other ways. For example, the rectifier circuit 130 can be a full bridge rectifier circuit and/or a voltage doubling circuit. The voltage doubler circuit includes a charge pump or other boost circuit. For example, FIG. 3 is a schematic diagram showing another example circuit of the rectifier circuit 130 shown in FIG. 1. Referring to FIG. 3, the rectifier circuit 130 includes an input capacitor Ci, an output capacitor Co, a first diode D1, and a second diode D2. The first end of the input capacitor Ci is coupled to the first end of the secondary side coil 122 of the transformer 120. The cathode of the first diode D1 is coupled to the second end of the input capacitor Ci. The anode of the first diode D1 is coupled to the second end of the secondary side coil 122 of the transformer 120. The anode of the second diode D2 is coupled to the second end of the input capacitor Ci. The cathode of the second diode D2 serves as an output terminal of the rectifier circuit 130. The first end of the output capacitor Co is coupled to the cathode of the second diode D2. The second end of the output capacitor Co is coupled to the second end of the secondary side coil 122 of the transformer 120.

When the AC signal of the secondary side coil 122 is a negative half cycle, it is assumed that the maximum amplitude of the AC signal is Am, since the first diode D1 is biased and the second diode D2 is reverse biased, so the input The capacitor Ci stores a voltage of approximately Am. When the AC signal of the secondary side coil 122 is a positive half cycle, the first diode D1 is reverse biased, and thus the AC signal and the storage voltage of the capacitor Ci are superimposed on each other. Since the second diode D2 is forward biased, the superimposed voltage (ie, Am+Am) is stored to the output capacitor Co via the second diode D2. Therefore, the DC target voltage Vout supplied from the output terminal of the rectifier circuit 130 (i.e., the cathode of the second diode D2) is approximately 2 Am.

FIG. 4 is a functional block diagram illustrating a large dynamic range voltage generator 500 in accordance with yet another embodiment of the present disclosure. The voltage generator 500 includes an adjustable voltage source 410, a switching crystal circuit 110, a transformer 120, a rectifier circuit 130, and a feedback circuit 510. The output of the adjustable voltage source 410 is coupled to the switching crystal circuit 110 to provide a source voltage Vs. The adjustable voltage source 410 adjusts the source voltage Vs in accordance with the control signal Sc2. The switching crystal circuit 110 is coupled to the primary side coil 121 of the transformer 120. The switching crystal circuit 110 drives the primary side coil 121 using the source voltage Vs in accordance with the modulation signal Sm. The input end of the rectifier circuit 130 is coupled to the secondary side coil 122 of the transformer 120. The output of the rectifier circuit 130 provides the target voltage Vout as the output of the voltage generator 500. The input end of the feedback circuit 510 is coupled to the output of the rectifier circuit 130. The output of the feedback circuit 510 provides a modulated signal Sm to the switching crystal circuit 110. The feedback circuit 510 adjusts the modulation signal Sm according to the target voltage Vout.

In the present embodiment, the feedback circuit 510 includes a voltage dividing circuit 511, an error amplifier 151, and a pulse width modulation module 152. The input end of the voltage dividing circuit 511 is coupled to the output end of the rectifying circuit 130. The output terminal of the voltage dividing circuit 511 provides a feedback voltage Vfb. The first input end of the error amplifier 151 is coupled to the output of the voltage dividing circuit 511 to receive the feedback voltage Vfb. The second input of the error amplifier 151 is coupled to the reference voltage Vref. The input end of the pulse width modulation module 152 is coupled to the output of the error amplifier 151. The output of the pulse width modulation module 152 is coupled to the switching crystal circuit 110 to provide a modulation signal Sm. The pulse width modulation module 152 adjusts the pulse width of the modulation signal Sm according to the output of the error amplifier 151.

For the embodiment shown in FIG. 4, reference may be made to the related description of FIG. 1 and FIG. Different from the embodiment shown in Fig. 2, in the embodiment shown in Fig. 4, the upper resistor Ru and the lower resistor Rd have a fixed resistance value. The first end of the upper resistor Ru is coupled to the output of the rectifier circuit 130. The second end of the upper resistor Ru serves as an output terminal of the voltage dividing circuit 511. The first end of the lower resistor Rd is coupled to the second end of the upper resistor Ru. The second end of the lower resistor Rd is coupled to the second end of the secondary side coil 122 of the transformer 120. That is to say, the resistance ratio of the voltage dividing circuit 511 of the present embodiment is Ru: Rd is a fixed resistance value.

In summary, the above embodiments enable the voltage generator to increase the dynamic range of the target voltage by adjusting the voltage division ratio of the voltage dividing circuit and/or adjusting the voltage amplitude of the voltage source.

The present disclosure has been disclosed in the above embodiments, but it is not intended to limit the disclosure, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the disclosure. The scope of protection of this disclosure is subject to the definition of the scope of the patent application.

100, 400, 500. . . Voltage generator

110. . . Switching crystal circuit

111. . . wire

112. . . Switching crystal

141~143, 411~413. . . switch

120. . . transformer

121. . . Primary side coil

122. . . Secondary side coil

130. . . Rectifier circuit

140. . . Adjustable voltage dividing circuit

150, 510. . . Feedback circuit

151. . . Error amplifier

152. . . Pulse width modulation module

410. . . Adjustable voltage source

511. . . Voltage dividing circuit

C1, Ci, Co. . . capacitance

D1, D2. . . Dipole

Ru, Rd, Rd1, Rd2, Rd3. . . resistance

S1~S6. . . Switching signal

Sc1, Sc2. . . control signal

Sm. . . Modulated signal

VDC1~VDC3. . . DC voltage

Vfb. . . Feedback voltage

Vout. . . Target voltage

Vref. . . Reference voltage

Vs. . . Source voltage

1 is a functional block diagram illustrating a large dynamic range voltage generator in accordance with an embodiment of the present disclosure.

2 is a functional block diagram illustrating a large dynamic range voltage generator in accordance with another embodiment of the present disclosure.

FIG. 3 is a schematic diagram showing another example circuit of the rectifier circuit shown in FIG. 1. FIG.

4 is a functional block diagram illustrating a large dynamic range voltage generator in accordance with yet another embodiment of the present disclosure.

400. . . Voltage generator

110. . . Switching crystal circuit

111. . . wire

112. . . Switching crystal

141~143, 411~413. . . switch

120. . . transformer

121. . . Primary side coil

122. . . Secondary side coil

130. . . Rectifier circuit

140. . . Adjustable voltage dividing circuit

150. . . Feedback circuit

151. . . Error amplifier

152. . . Pulse width modulation module

410. . . Adjustable voltage source

C1. . . capacitance

D1. . . Dipole

Ru, Rd1, Rd2, Rd3. . . resistance

S1~S6. . . Switching signal

Sc1, Sc2. . . control signal

Sm. . . Modulated signal

VDC1~VDC3. . . DC voltage

Vfb. . . Feedback voltage

Vout. . . Target voltage

Vref. . . Reference voltage

Vs. . . Source voltage

Claims (23)

A large dynamic range voltage generator includes: a transformer having at least a primary side coil and a secondary side coil; a switching crystal circuit coupled to the primary side coil of the transformer, the switching crystal circuit being used according to a modulation signal a source voltage drives the primary side coil; a rectifier circuit having an input end coupled to the secondary side coil of the transformer, the output end of the rectifier circuit providing a target voltage as an output of the voltage generator; a voltage circuit having an input end coupled to the output end of the rectifier circuit, the output end of the adjustable voltage dividing circuit providing a feedback voltage, wherein the voltage dividing ratio of the adjustable voltage dividing circuit is controlled by a first a control signal; a feedback circuit having an input coupled to the output of the adjustable voltage divider circuit, the output of the feedback circuit providing the modulated signal to the switching crystal circuit, wherein the feedback circuit is compared The feedback voltage and a reference voltage, and adjusting the modulation signal according to the comparison result; and an adjustable voltage source, the output end of which is coupled to the switching crystal circuit to provide the source voltage, wherein the Adjusting the voltage source voltage source in accordance with a second control signal. The voltage generator of the large dynamic range as described in claim 1 , wherein the switching crystal circuit is a flyback power conversion circuit, a push-pull power conversion circuit, a forward power conversion circuit, and a half bridge power conversion circuit. Or full bridge power conversion circuit. The voltage generator of the large dynamic range of claim 1, wherein the switching crystal circuit comprises: a wire, the first end of which receives the source voltage, and the second end of the wire is coupled to the primary side of the transformer a first end of the coil; and a switching crystal, the first end of which is coupled to the second end of the primary side coil of the transformer, the second end of the switching crystal is grounded, and the control end of the switching crystal is coupled to the feedback A circuit to receive the modulated signal. The voltage generator of the large dynamic range of claim 1, wherein the rectifier circuit comprises: a diode having an anode coupled to the first end of the secondary side coil of the transformer, the diode a cathode is used as an output end of the rectifier circuit; and a capacitor has a first end coupled to the cathode of the diode, and a second end of the capacitor coupled to the second end of the secondary side coil of the transformer. A large dynamic range voltage generator as claimed in claim 1, wherein the rectifier circuit rectifies and doubles the output of the secondary side coil of the transformer to provide the target voltage. The voltage generator of the large dynamic range of claim 1, wherein the first control signal comprises a first switching signal and a second switching signal, and the adjustable voltage dividing circuit comprises: an upper resistor, The first end is coupled to the output end of the rectifying circuit, and the second end of the upper resistor is used as an output end of the adjustable voltage dividing circuit; a first switch having a first end coupled to the second end of the upper resistor The first end of the first switch is coupled to the second end of the first switch, and the second end of the first lower resistor is coupled to the first end a second end of the secondary side coil of the transformer; a second switch having a first end coupled to the second end of the upper resistor, a control end of the second switch receiving the second switch signal; and a second a second end of the second lower resistor is coupled to the second end of the secondary side coil of the transformer; wherein the first lower resistor is coupled to the second end of the second switch The resistance is different from the resistance of the second lower resistor. The voltage generator of the large dynamic range of claim 1, wherein the feedback circuit comprises: an error amplifier, the first input end of which is coupled to the output end of the adjustable voltage dividing circuit to receive the back a voltage input, the second input end of the error amplifier is coupled to the reference voltage; and a pulse width modulation module, the input end of which is coupled to the output end of the error amplifier, and the pulse width modulation module The output end is coupled to the switching crystal circuit to provide the modulated signal, wherein the pulse width modulation module adjusts the pulse width of the modulated signal correspondingly according to the output of the error amplifier. The voltage generator of the large dynamic range of claim 1, wherein the second control signal comprises a first switch signal and a second switch signal, the adjustable voltage source comprises: a first switch, the first Receiving a first DC voltage at one end, a second end of the first switch is coupled to an output end of the adjustable voltage source, a control end of the first switch receives the first switch signal, and a second switch The first end receives a second DC voltage, the second end of the second switch is coupled to the output of the adjustable voltage source, and the control end of the second switch receives the second switch signal; wherein the first DC voltage Different from the second DC voltage. A large dynamic range voltage generating method includes: providing a transformer having at least a primary side coil and a secondary side coil; providing a switching crystal circuit coupled to the primary side coil of the transformer; The switching crystal circuit drives the primary side coil using a source voltage according to a modulation signal; providing a rectifier circuit, the input end of the rectifier circuit is coupled to the secondary side coil of the transformer; and the target is provided by the output end of the rectifier circuit The voltage is used as the output of the voltage generator; an adjustable voltage dividing circuit is provided, the input end of the adjustable voltage dividing circuit is coupled to the output end of the rectifier circuit; and the output end of the adjustable voltage dividing circuit Providing a feedback voltage, wherein the voltage division ratio of the adjustable voltage dividing circuit is controlled by a first control signal; providing a feedback circuit, the input end of the feedback circuit being coupled to the adjustable voltage dividing circuit The output terminal compares the feedback voltage with a reference voltage by the feedback circuit, and adjusts the modulation signal according to the comparison result to provide the modulation signal to the switching crystal circuit; Regulated voltage source, the adjustable voltage source output terminal is coupled to the switching circuit crystal; and adjusting the source voltage in accordance with a second control signal generated by the adjustable voltage source to provide the voltage to the source of the switching transistor circuit. The method for generating a large dynamic range voltage according to claim 9 , wherein the switching crystal circuit is a flyback power conversion circuit, a push-pull power conversion circuit, a forward power conversion circuit, and a half bridge power conversion circuit. Or full bridge power conversion circuit. The method for generating a large dynamic range according to claim 9 further includes: rectifying and doubling the output of the secondary side coil of the transformer by the rectifier circuit to provide the target voltage. The method for generating a large dynamic range voltage according to claim 9 , wherein the step of providing a feedback voltage by the output end of the adjustable voltage dividing circuit comprises: adjusting the adjustable according to the first control signal The resistance of a first lower resistor of the voltage dividing circuit and the resistance of a second lower resistor determine a voltage dividing ratio of the adjustable voltage dividing circuit. A large dynamic range voltage generator includes: a transformer having at least a primary side coil and a secondary side coil; a switching crystal circuit coupled to the primary side coil of the transformer, the switching crystal circuit being used according to a modulation signal a source voltage driving the primary side coil; an adjustable voltage source having an output coupled to the switching crystal circuit to provide the source voltage, wherein the adjustable voltage source adjusts the source voltage according to a control signal; a rectifier circuit, The input end is coupled to the secondary side coil of the transformer, the output end of the rectifier circuit provides a target voltage as an output of the voltage generator, and a feedback circuit having an input coupled to the output of the rectifier circuit The output end of the feedback circuit provides the modulation signal to the switching crystal circuit, wherein the feedback circuit adjusts the modulation signal according to the target voltage. The voltage generator of the large dynamic range according to claim 13 , wherein the switching crystal circuit is a flyback power conversion circuit, a push-pull power conversion circuit, a forward power conversion circuit, and a half bridge power conversion circuit. Or full bridge power conversion circuit. The voltage generator of the large dynamic range according to claim 13 , wherein the switching crystal circuit comprises: a wire having a first end coupled to the output end of the adjustable voltage source to receive the source voltage, the wire The second end is coupled to the first end of the primary side coil of the transformer; and a switching crystal having a first end coupled to the second end of the primary side coil of the transformer, the second end of the switching crystal being grounded, The control end of the switching crystal is coupled to the feedback circuit to receive the modulation signal. The voltage generator of the large dynamic range according to claim 13 , wherein the rectifier circuit comprises: a diode having an anode coupled to the first end of the secondary side coil of the transformer, the diode a cathode is used as an output end of the rectifier circuit; and a capacitor has a first end coupled to the cathode of the diode, and a second end of the capacitor coupled to the second end of the secondary side coil of the transformer. A voltage generator of a large dynamic range as described in claim 13 wherein the rectifier circuit rectifies and doubles the output of the secondary side coil of the transformer to provide the target voltage. The voltage generator of the large dynamic range according to claim 13 , wherein the feedback circuit comprises: a voltage dividing circuit, the input end of which is coupled to the output end of the rectifier circuit, and the output of the voltage dividing circuit Providing a feedback voltage; an error amplifier having a first input coupled to the output of the voltage divider circuit for receiving the feedback voltage, the second input of the error amplifier being coupled to the reference voltage; a pulse width modulation module, the input end of which is coupled to the output end of the error amplifier, and the output end of the pulse width modulation module is coupled to the switching crystal circuit to provide the modulated signal, wherein the pulse The wave width modulation module adjusts the pulse width of the modulation signal correspondingly according to the output of the error amplifier. The voltage generator of the large dynamic range according to claim 18, wherein the voltage dividing circuit comprises: an upper resistor, the first end of which is coupled to the output end of the rectifier circuit, and the second end of the upper resistor serves as An output end of the voltage dividing circuit; and a lower resistor, the first end of which is coupled to the second end of the upper resistor, and the second end of the lower resistor is coupled to the second end of the secondary side coil of the transformer. The voltage generator of the large dynamic range according to claim 13 , wherein the control signal comprises a first switch signal and a second switch signal, the adjustable voltage source comprises: a first switch, the first end thereof Receiving a first DC voltage, the second end of the first switch is coupled to the output end of the adjustable voltage source, the control end of the first switch receives the first switch signal; and a second switch is first Receiving a second DC voltage, the second end of the second switch is coupled to the output end of the adjustable voltage source, and the control end of the second switch receives the second switch signal; wherein the first DC voltage is different from The second DC voltage. A large dynamic range voltage generating method includes: providing a transformer having at least a primary side coil and a secondary side coil; providing a switching crystal circuit coupled to the primary side coil of the transformer; The switching crystal circuit drives the primary side coil according to a modulation signal by using a source voltage; providing an adjustable voltage source, the output end of the adjustable voltage source is coupled to the switching crystal circuit; and the adjustable voltage source is controlled according to a control The signal is adjusted to provide the source voltage to the switching crystal circuit; a rectifying circuit is provided, the input end of the rectifying circuit is coupled to the secondary side coil of the transformer; and a target voltage is provided by the output end of the rectifying circuit Providing an output of the voltage generator; providing a feedback circuit, an input end of the feedback circuit coupled to an output end of the rectifier circuit; and providing the modulation signal to the switching crystal by an output end of the feedback circuit a circuit, wherein the feedback circuit adjusts the modulation signal according to the target voltage. The method for generating a large dynamic range voltage according to claim 21, wherein the switching crystal circuit is a flyback power conversion circuit, a push-pull power conversion circuit, a forward power conversion circuit, and a half bridge power conversion circuit. Or full bridge power conversion circuit. The method for generating a large dynamic range according to claim 21, further comprising: rectifying and doubling the output of the secondary side coil of the transformer by the rectifier circuit to provide the target voltage.