Direct current converter, power amplifier system and battery system

Abstract

The invention discloses a direct-current converter, a power amplifier system and a battery system, the direct-current converter comprises a power supply module and N bridge arms, each bridge arm comprises a first controllable switch and a second controllable switch which are alternately conducted, and the first end of the first controllable switch is connected with the first end of the power supply module; m inductance units and N dynamic voltage stabilizing points, when N is equal to 1, the direct-current converter further comprises a first capacitor and a second capacitor, the first end of the first capacitor is connected with the first end of the power supply module, the second end of the first capacitor and the first end of the second capacitor are connected to a dynamic voltage stabilization point, and the second end of the second capacitor is connected with the second end of the power supply module, so that two output voltages connected in series are formed; or when N is greater than or equal to 2, the direct-current converter comprises a plurality of third capacitors, and the third capacitors are respectively arranged between adjacent N dynamic voltage stabilizing points so as to form at most N-1 series output voltages. The direct-current converter can generate positive voltage and negative voltage, so that the cost and the power consumption are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of basic electronic circuits, and in particular to a DC converter, a power amplifier system, and a battery system. Background Art

[0002] In modern electronic devices, the components involved are becoming more and more complex and precise. Many components require the electronic devices to provide them with a stable power supply, such as the operational amplifier, which is a basic component constituting basic circuits such as a sampling circuit and a conditioning circuit. Since these components have relatively high requirements for the stability of the power supply, a certain DC converter must be used to provide them with a reliable power supply. A DC (DC-DC) converter is a commonly used DC converter in electronic devices.

[0003] DC converters generally adopt isolated switched DC converters, such as boost (step-up) circuits, buck (step-down) circuits, and buck-boost (step-up / step-down) circuits. Among them, the boost circuit is used to boost the input voltage and then stably output it, the buck circuit is used to step down the input voltage and then stably output it, and the buck-boost circuit is used to invert the polarity of the input voltage and then step up / step down the output.

[0004] Currently, a DC converter can only provide one voltage, either only output a positive voltage or only output a negative voltage, and it cannot output both a positive voltage and a negative voltage. Summary of the Invention

[0005] The present invention provides a DC converter, a power amplifier system, and a battery system, which can output both positive voltage and negative voltage.

[0006] In a first aspect, an embodiment of the present invention provides a DC converter, including: a power supply module for providing a first DC voltage; N bridge arms, each bridge arm including a first controllable switch and a second controllable switch that conduct alternately. A first end of the first controllable switch is connected to a first end of the power supply module, a second end of the first controllable switch and a first end of the second controllable switch are connected to a first node, a second end of the second controllable switch is connected to a second end of the power supply module, and control ends of the first controllable switch and the second controllable switch are both connected to a PWM control signal; N is a positive integer; M inductance units and N dynamic voltage stabilizing points, the dynamic voltage stabilizing points are arranged in one-to-one correspondence with the first node, a first end of the inductance unit is correspondingly connected to the first node, and a second end of the inductance unit is correspondingly connected to the dynamic voltage stabilizing point; M is a positive integer less than or equal to N; when N = 1, the DC converter further includes a first capacitor and a second capacitor, a first end of the first capacitor is connected to a first end of the power supply module, a second end of the first capacitor and a first end of the second capacitor are connected to the dynamic voltage stabilizing point, and a second end of the second capacitor is connected to a second end of the power supply module to form two series-connected output voltages; or, when N is greater than or equal to 2, the DC converter includes a plurality of third capacitors, and the third capacitors are respectively arranged between adjacent N dynamic voltage stabilizing points to form at most N - 1 series-connected output voltages; wherein the output voltage includes at least one positive voltage and at least one negative voltage output simultaneously, or includes at least one voltage with adjustable positive and negative polarities.

[0007] Optionally, when N is greater than or equal to 2, the DC converter further includes a fourth capacitor and / or a fifth capacitor; a first end of the fourth capacitor is connected to a first end of the power supply module, and a second end of the fourth capacitor is connected to a dynamic voltage stabilizing point adjacent to the first end of the power supply module; a first end of the fifth capacitor is connected to a second end of the power supply module, and a second end of the fifth capacitor is connected to a dynamic voltage stabilizing point adjacent to the second end of the power supply module.

[0008] Optionally, the DC converter further includes N PWM control signal generation modules, an input end of the PWM control signal generation module is connected to the corresponding dynamic voltage stabilizing point, a first output end of the PWM control signal generation module is connected to the corresponding first controllable switch, and a second output end of the PWM control signal generation module is connected to a control end of the corresponding second controllable switch for generating a PWM control signal.

[0009] Optionally, the duty cycles of the PWM control signals generated by different PWM control signal generation modules are different.

[0010] Optionally, the PWM control signal generation module includes an operational amplifier, a comparator, an inverter, a sixth capacitor, a first resistor, a second resistor, a third resistor, and a fourth resistor; the first end of the first resistor serves as the input end of the PWM control signal generation module, the second end of the first resistor is connected to the inverting input end of the operational amplifier, the first end of the second resistor, and the first end of the third resistor, the non-inverting input end of the operational amplifier is connected to a reference voltage, the second end of the second resistor is grounded, and the second end of the third resistor is connected to a voltage regulation control signal; the first end of the fourth resistor is connected to the inverting input end of the operational amplifier, the second end of the fourth resistor is connected to the first end of the sixth capacitor, the second end of the sixth capacitor is connected to the non-inverting input end of the comparator, the inverting input end of the comparator is connected to a triangular wave signal, the output end of the comparator is connected to the first end of the inverter and serves as the first output end of the PWM control generation module, and the second end of the inverter serves as the second output end of the PWM control generation module.

[0011] Optionally, the power supply module includes one or more of a boost module, a buck module, a buck-boost module, and a floating voltage current source.

[0012] Optionally, the power supply module includes a voltage conversion unit, an isolation unit, and a rectification unit; the voltage conversion unit is connected to a second DC voltage and is configured to convert the second DC voltage into an AC voltage; the isolation unit is respectively connected to the voltage conversion unit and the rectification unit and is configured to isolate the voltage conversion unit and the rectification unit; the rectification unit is configured to convert the AC voltage into a first DC voltage.

[0013] Optionally, the voltage values of the positive voltage and the negative voltage are associated with the duty cycles of the PWM control signals applied to the control terminals of the first controllable switch and the second controllable switch on the corresponding bridge arm.

[0014] In a second aspect, an embodiment of the present invention provides a power amplifier system, including the DC converter provided in any embodiment of the present invention, and further including a CLASS D type power amplifier or a CLASS G type power amplifier; when the DC converter outputs at least one positive and negative adjustable voltage, the DC converter is configured to supply power to the CLASS D type power amplifier; when the number N of bridge arms in the DC converter is greater than or equal to 3, the number M of inductor units is greater than or equal to 3, and the DC converter includes a fourth capacitor and a fifth capacitor, the DC converter is configured to simultaneously output at least two positive voltages and at least two negative voltages to supply power to the Class G type power amplifier.

[0015] In a third aspect, an embodiment of the present invention provides a battery system, which includes the DC converter provided in any embodiment of the present invention, and further includes a plurality of batteries connected in series. When the number N of bridge arms in the DC converter is greater than or equal to 3, the number M of inductor units is greater than or equal to 3, and the DC converter includes a fourth capacitor and a fifth capacitor, the DC converter includes multiple sets of output terminals, and each set of output terminals is connected to a battery to charge the battery.

[0016] The DC converter provided by the embodiment of the present invention includes a power supply module, N bridge arms, M inductor units, and N dynamic voltage stabilizing points. The control terminals of the first controllable switch and the second controllable switch on the bridge arm are connected to a PWM control signal. By adjusting the duty cycle of the PWM control signal of each bridge arm, the voltage of each dynamic voltage stabilizing point can be flexibly controlled. When the duty cycle of the PWM control signal changes between 0% and 100%, the voltage of the dynamic voltage stabilizing point can be continuously adjusted between 0V and the voltage of the power supply module. Multiple dynamic voltage stabilizing points formed by multiple bridge arms and the fixed voltage points at both ends of the power supply module, as well as between adjacent dynamic voltage stabilizing points, are connected by capacitors to form a series output voltage rail, so as to realize the simultaneous output of at least one positive voltage and at least one negative voltage, or the output of a voltage that can be positive or negative in a period. For example, when there are three bridge arms, three dynamic voltage stabilizing points Va, Vb, and Vc can be formed. By reasonably setting the duty cycle of the PWM control signal, different series output voltage combinations such as Va - Vb and Vc - Vb can be obtained. These voltage combinations can meet the requirements of different circuits for positive and negative voltages and different voltage values, and thus are widely used in devices that require multiple voltage power supplies such as power amplifier systems and battery systems.

[0017] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0019] Figure 1 is a schematic structural diagram of a DC converter provided by an embodiment of the present invention;

[0020] Figure 2 is a schematic structural diagram of a second optional DC converter provided by an embodiment of the present invention;

[0021] Figure 3It is a schematic structural diagram of the third optional DC converter provided by an embodiment of the present invention;

[0022] Figure 4 It is a schematic structural diagram of the fourth optional DC converter provided by an embodiment of the present invention;

[0023] Figure 5 It is a schematic structural diagram of the fifth optional DC converter provided by an embodiment of the present invention;

[0024] Figure 6 It is a schematic structural diagram of the sixth optional DC converter provided by an embodiment of the present invention;

[0025] Figure 7 It is a schematic structural diagram of the seventh optional DC converter provided by an embodiment of the present invention;

[0026] Figure 8 It is a schematic structural diagram of the eighth optional DC converter provided by an embodiment of the present invention;

[0027] Figure 9 It is a schematic structural diagram of the ninth optional DC converter provided by an embodiment of the present invention;

[0028] Figure 10 It is a schematic structural diagram of the tenth optional DC converter provided by an embodiment of the present invention;

[0029] Figure 11 It is a schematic structural diagram of the eleventh optional DC converter provided by an embodiment of the present invention;

[0030] Figure 12 It is a schematic structural diagram of the twelfth optional DC converter provided by an embodiment of the present invention;

[0031] Figure 13 It is a schematic structural diagram of a power amplifier system provided by an embodiment of the present invention;

[0032] Figure 14 It is a schematic structural diagram of another power amplifier system provided by an embodiment of the present invention;

[0033] Figure 15 It is a schematic structural diagram of a battery system provided by an embodiment of the present invention;

[0034] Figure 16 It is a schematic structural diagram of a battery system provided by the related art. Detailed implementation manners

[0035] To enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the technical solution in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0036] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion.

[0037] Figure 1 is a schematic structural diagram of a DC converter provided by an embodiment of the present invention. Figure 2 is a schematic structural diagram of a second optional DC converter provided by an embodiment of the present invention. Figure 3 is a schematic structural diagram of a third optional DC converter provided by an embodiment of the present invention. Figure 4 is a schematic structural diagram of a fourth optional DC converter provided by an embodiment of the present invention. Refer to Figures 1 to 4 , the DC converter includes:

[0038] A power supply module 11 for providing a first DC voltage Vin1.

[0039] N bridge arms 12, the bridge arm 12 includes a first controllable switch and a second controllable switch that conduct alternately. The first end of the first controllable switch is connected to the first end of the power supply module 11, the second end of the first controllable switch and the first end of the second controllable switch are connected to a first node N1, the second end of the second controllable switch is connected to the second end of the power supply module 11, and the control ends of the first controllable switch and the second controllable switch are both connected to a PWM control signal; N is a positive integer.

[0040] M inductance units and N dynamic voltage stabilizing points N2, the first end of the inductance unit is correspondingly connected to the first node N1, and the second end of the inductance unit is correspondingly connected to the dynamic voltage stabilizing point N2; M is a positive integer greater than or equal to N.

[0041] Continue to refer to Figure 1, when N = 1, the DC converter further includes a first capacitor C1 and a second capacitor C2. The first end of the first capacitor C1 is connected to the first end of the power supply module 11. The second end of the first capacitor C1 and the first end of the second capacitor C2 are connected to the dynamic voltage stabilization point N2. The second end of the second capacitor C2 is connected to the second end of the power supply module 11. Through a dynamic voltage stabilization point N2 and two fixed voltage points at both ends of the power supply module, two series output voltages are formed.

[0042] Continue to refer to Figures 2 to 4 , when N is greater than or equal to 2, the DC converter further includes a plurality of third capacitors C3. The third capacitors C3 are respectively arranged between adjacent N dynamic voltage stabilization points N2 to form at most N - 1 series output voltages; wherein the output voltages include at least one positive voltage and at least one negative voltage output simultaneously, or include at least one voltage with adjustable positive and negative polarities.

[0043] Through the above embodiments, the present application proposes a new DC converter. Compared with the conventional unipolar or single - path DC converter, and the method with relatively high requirements for input isolation characteristics when multiple DC converters are connected in series, the DC converter proposed in the present application can achieve compatibility of positive - negative voltage topologies and reduce the requirements for input isolation. Through one or more bridge - type switching tubes, combined with an LC filter circuit to form one or more voltage stabilization points, and using the voltage difference between one or more formed dynamic voltage stabilization points and the first or second end of the power supply module to form a differential output voltage, this differential output voltage can be either positive or negative, and at the same time, it can also conveniently form multiple series output voltage rails.

[0044] Specifically, the duty cycles of the PWM control signals applied to the control terminals of the first controllable switch and the second controllable switch on the same bridge arm 12 are complementary. Refer to Figure 1 , the control terminal of the first controllable switch T11 on the first bridge arm 121 is connected to the first PWM control signal PWM1, and the control terminal of the second controllable switch T21 on the first bridge arm 121 is connected to the second PWM control signal PWM2. Refer to Figure 2 And Figure 3 , the control terminal of the first controllable switch T11 on the first bridge arm 121 is connected to the first PWM control signal PWM1, and the control terminal of the second controllable switch T21 is connected to the second PWM control signal PWM2. The control terminal of the first controllable switch T12 on the second bridge arm 122 is connected to the third PWM control signal PWM3, and the control terminal of the second controllable switch T22 is connected to the fourth PWM control signal PWM4. Refer to Figure 4, the control terminal of the first controllable switch T11 on the first bridge arm 121 is connected to the first PWM control signal PWM1, and the control terminal of the second controllable switch T21 on the first bridge arm 121 is connected to the second PWM control signal PWM2. The control terminal of the first controllable switch T12 on the second bridge arm 122 is connected to the third PWM control signal PWM3, and the control terminal of the second controllable switch T22 on the second bridge arm 122 is connected to the fourth PWM control signal PWM4. The control terminal of the first controllable switch T13 on the third bridge arm 123 is connected to the fifth PWM control signal PWM5, and the control terminal of the second controllable switch T23 on the third bridge arm 123 is connected to the sixth PWM control signal PWM6. Among them, the first PWM control signal PWM1 and the second PWM control signal PWM2 are complementary signals. The third PWM control signal PWM3 and the fourth PWM control signal PWM4 are complementary signals. The fifth PWM control signal PWM5 and the sixth PWM control signal PWM6 are complementary signals. Such signals with alternating high and low levels ensure that the first controllable switch and the second controllable switch conduct alternately.

[0045] It should be noted that the types of the first controllable switch and the second controllable switch on different bridge arms can be the same or different. Correspondingly, the voltages of the common nodes (i.e., the first node N1) of the first controllable switch and the second controllable switch are also different.

[0046] To distinguish the situations of the first node N1 of different bridge arms, in the embodiments of the present invention and the following embodiments, the first node N1 on the first bridge arm 121 is referred to as the first sub-node N11, the first node N1 on the second bridge arm 122 is referred to as the second sub-node N12, and the first node N1 on the third bridge arm 123 is referred to as the third sub-node N13.

[0047] The duty cycle refers to the ratio of the duration of the conduction level to the entire cycle time within a pulse cycle. It is expressed by the formula: duty cycle where t on is the duration of the conduction level, T is the pulse cycle, T = t on + t off , t off is the duration of the turn-off level.

[0048] In the embodiments of the present invention, the duty cycle is calculated based on the proportion of the duration of the conduction level of the first controllable switch relative to the entire cycle time. For example, if the cycle of a PWM control signal is 10 ms and the duration of the conduction level of the first controllable switch is 4 ms, then the duty cycle D of this PWM control signal is 40%.

[0049] The voltage values of the positive voltage and the negative voltage are associated with the duty cycles of the PWM control signals applied to the control terminals of the first controllable switch and the second controllable switch on the corresponding leg. Exemplarily, referring to Figure 1 , when the DC converter includes only the first leg 121, the voltage values of the positive voltage and the negative voltage are associated with the duty cycles of the first PWM control signal PWM1 and the second PWM control signal PWM2, wherein the duty cycles of the first PWM control signal PWM1 and the second PWM control signal PWM2 are complementary. Exemplarily, if the first DC voltage Vin1 is 10V, when the duty cycle of the first PWM control signal PWM1 is 0%, the voltage at the dynamic voltage regulation point N2 is 0V. When the duty cycle of the first PWM control signal PWM1 is 100%, the voltage at the dynamic voltage regulation point N2 is 10V. That is, the voltage range of the dynamic voltage regulation point is between 0 volts and 10 volts. Through the above embodiments, on the basis of a fixed bias voltage of +10V and -10V respectively, by adjusting the distribution of the intermediate voltage, the maximum positive and negative voltage spans can be achieved.

[0050] When the duty cycle of the first PWM control signal PWM1 is 50%, the voltage at the dynamic voltage regulation point N2 is 5V. At this time, the dynamic voltage regulation point N2 can be set as the reference ground. Then, the voltage difference between the voltage at the first end of the power supply module 11 and the voltage at the dynamic voltage regulation point N2 is 5V, and the voltage difference between the voltage at the second end of the power supply module 11 and the voltage at the dynamic voltage regulation point N2 is -5V. That is, the voltage value of the positive voltage output by the DC converter at this time is 5V, and the voltage value of the negative voltage output is -5V.

[0051] When the duty cycle of the first PWM control signal PWM1 is 80%, the voltage at the dynamic voltage regulation point N2 is 8V. Let the dynamic voltage regulation point N2 be the reference ground. Then, the voltage difference between the voltage at the first end of the power supply module 11 and the voltage at the dynamic voltage regulation point N2 is 2V, and the voltage difference between the voltage at the second end of the power supply module 11 and the voltage at the dynamic voltage regulation point N2 is -8V. That is, the voltage value of the positive voltage output by the DC converter at this time is 2V, and the voltage value of the negative voltage output is -8V. That is, the positive voltage output by the DC converter is adjustable, and the negative voltage output is also adjustable.

[0052] Referring to Figure 2 and Figure 3 , similar to the Figure 1 principle, when the DC converter includes the first leg 121 and the second leg 122, the voltage values of the positive voltage and the negative voltage are associated with the duty cycles of the first PWM control signal PWM1 and the third PWM control signal PWM3. Among them, the control terminal of the first controllable switch T11 on the first leg 121 is connected to the first PWM control signal PWM1, and the control terminal of the first controllable switch T12 on the second leg 122 is connected to the third PWM control signal PWM3.

[0053] Exemplarily, if the first DC voltage Vin1 is 10V, when the duty cycle of the first PWM control signal PWM1 is 20%, the voltage of the first dynamic voltage stabilizing point Va is 2V. When the duty cycle of the third PWM control signal PWM3 is 60%, the voltage of the second dynamic voltage stabilizing point Vb is 6V. Then, the voltage difference across the third capacitor C3 is -4V. When the duty cycle of the first PWM control signal PWM1 is 60%, the voltage of the first dynamic voltage stabilizing point Va is 6V. When the duty cycle of the third PWM control signal PWM3 is 20%, the voltage of the second dynamic voltage stabilizing point Vb is 2V. Then, the voltage difference across the third capacitor C3 is 4V. That is to say, this DC converter can output both positive and negative voltages. At the same time, by adjusting the duty cycles of the first PWM control signal PWM1 and the third PWM control signal PWM3, adjustable positive and negative voltages can be output.

[0054] When M is equal to N, the first end of the inductor unit is correspondingly connected to the first node N1 one by one, and the second end of the inductor unit is correspondingly connected to the dynamic voltage stabilizing point N2 one by one. When M = 1, the first end of the inductor unit is connected to any one of the first nodes N1, and the second end of the inductor unit is connected to any one of the dynamic voltage stabilizing points N2.

[0055] As an alternative embodiment provided by the embodiment of the present invention, the inductor unit includes a first inductor L1. The first end of the first inductor L1 serves as the first end of the inductor unit, and the second end of the first inductor L1 serves as the second end of the inductor unit.

[0056] It should be noted that the types of the first inductors L1 corresponding to different bridge arms can be the same or different. Referring to Figures 1 to 4 , in the embodiment of the present invention, the first inductor L1 corresponding to the first bridge arm 121 is referred to as the first sub-inductor L11, the first inductor L1 corresponding to the second bridge arm 122 is referred to as the second sub-inductor L12, and the first inductor L1 corresponding to the third bridge arm 123 is referred to as the third sub-inductor L13.

[0057] Optionally, the inductance unit further includes K second inductors. The first end of the first second inductor is connected to the first end of the first inductor L1. The second end of the j-th second inductor is connected to the first end of the (j + 1)-th second inductor. The second end of the last second inductor serves as the second end of the inductance unit, where K is an integer greater than or equal to 1, and j is an integer greater than or equal to 1 and less than K. It should be noted that each embodiment of the present invention is described by taking the inductance unit including only the first inductor L1 as an example. That is to say, each output loop includes at least one filter inductor and one filter capacitor. Multiple filter inductors can be combined. The DC converter provided in this embodiment can provide positive voltage and positive current, or negative voltage and negative current. One application scenario is to charge the energy storage capacitor to complete the circuit task, and then quickly supply power in the reverse direction to quickly discharge the capacitor and safely cut off the power of the circuit.

[0058] Reference Figure 4 , and Figure 1 Based on the same principle, when the DC converter includes the first bridge arm 121, the second bridge arm 122, and the third bridge arm 123, the voltage values of the positive voltage and the negative voltage are associated with the duty cycles of the first PWM control signal PWM1, the third PWM control signal PWM3, and the fifth PWM control signal PWM5. Among them, the control terminal of the first controllable switch T11 on the first bridge arm 121 is connected to the first PWM control signal PWM1. The control terminal of the first controllable switch T12 on the second bridge arm 122 is connected to the third PWM control signal PWM3. The control terminal of the first controllable switch T13 on the third bridge arm 123 is connected to the fifth PWM control signal PWM5.

[0059] Exemplarily, if the first DC voltage Vin1 is 10V, when the duty cycle of the first PWM control signal PWM1 is 20%, the voltage of the first dynamic voltage stabilization point Va is 2V. When the duty cycle of the third PWM control signal PWM3 is 60%, the voltage of the second dynamic voltage stabilization point Vb is 6V. When the duty cycle of the fifth PWM control signal PWM5 is 20%, the voltage of the third dynamic voltage stabilization point Vc is 2V. At this time, the voltage difference across the first third capacitor C31 is -4V, and the voltage difference across the second third capacitor C32 is 4V.

[0060] When the duty cycle of the first PWM control signal PWM1 is 60%, the voltage of the first dynamic voltage stabilization point Va is 6V. When the duty cycle of the third PWM control signal PWM3 is 20%, the voltage of the second dynamic voltage stabilization point Vb is 2V. When the duty cycle of the fifth PWM control signal PWM5 is 60%, the voltage of the third dynamic voltage stabilization point Vc is 6V. At this time, the voltage difference across the first third capacitor C31 is 4V, and the voltage difference across the second third capacitor C32 is -4V. That is to say, this DC converter can output both positive and negative voltages simultaneously, and the output positive and negative voltages are adjustable.

[0061] The DC converter provided by the embodiment of the present invention includes a power supply module, N bridge arms, M inductor units, and N dynamic voltage stabilization points. The control terminals of the first controllable switch and the second controllable switch on the bridge arm are connected to the PWM control signal. By adjusting the duty cycle of the PWM control signal of each bridge arm, the voltage of each dynamic voltage stabilization point can be flexibly controlled. When the duty cycle of the PWM control signal changes between 0% and 100%, the voltage of the dynamic voltage stabilization point can be continuously adjusted between 0V and the voltage of the power supply module. Between the multiple dynamic voltage stabilization points formed by multiple bridge arms and the fixed voltage points at both ends of the power supply module, and between adjacent dynamic voltage stabilization points, capacitors are connected to form a series output voltage rail, so as to realize at least one positive voltage and at least one negative voltage output simultaneously, or a voltage that can be positive or negative in a period. For example, when there are three bridge arms, three dynamic voltage stabilization points Va, Vb, and Vc can be formed. By reasonably setting the duty cycle of the PWM control signal, different series output voltage combinations such as Va - Vb and Vc - Vb can be obtained. These voltage combinations can meet the requirements of different circuits for positive and negative voltages and different voltage values, and thus are widely used in devices that require multiple voltage power supplies such as power amplifier systems and battery systems.

[0062] Figure 5 It is a schematic structural diagram of the fifth optional DC converter provided by the embodiment of the present invention.

[0063] Figure 6 It is a schematic structural diagram of the sixth optional DC converter provided by the embodiment of the present invention. Refer to Figure 5 and Figure 6 Optionally, when N is greater than or equal to 2, the DC converter further includes a fourth capacitor C4 and / or a fifth capacitor C5.

[0064] The first end of the fourth capacitor C4 is connected to the first end of the power supply module 11, and the second end of the fourth capacitor C4 is connected to the dynamic voltage stabilization point N2 adjacent to the first end of the power supply module 11. The first end of the fifth capacitor C5 is connected to the second end of the power supply module 11, and the second end of the fifth capacitor C5 is connected to the dynamic voltage stabilization point N2 adjacent to the second end of the power supply module 11.

[0065] Through the above embodiments, by using N groups of bridge arms, N dynamic voltage regulation points can be formed. Together with the fixed voltage points at both ends of the power supply module (i.e., the input power supply rail), there are a total of N + 2 potentials, and at most N + 1 series output voltage rails can be formed. There are two types of forms that the output voltage can form: The output voltage is formed by LC filtering between two dynamic voltage regulation points. The output voltage is formed by LC filtering between a dynamic voltage regulation point and a fixed voltage point (one end of the input power supply rail).

[0066] Figure 7 is the structural schematic diagram of the seventh optional DC converter provided by the embodiment of the present invention. Refer to Figure 7 , optionally, the DC converter further includes N PWM control signal generation modules 13. The input end of the PWM control signal generation module 13 is connected to the corresponding dynamic voltage regulation point N2. The first output end of the PWM control signal generation module 13 is connected to the corresponding first controllable switch, and the second output end of the PWM control signal generation module 13 is connected to the control end of the corresponding second controllable switch, for generating PWM control signals. The duty cycles of the PWM control signals generated by different PWM control signal generation modules are different.

[0067] As a preferred implementation manner provided by the embodiment of the present invention, Figure 8 is the structural schematic diagram of the eighth optional DC converter provided by the embodiment of the present invention. Refer to Figure 8 , optionally, the PWM control signal generation module includes an operational amplifier U1, a comparator U2, an inverter U3, a sixth capacitor C6, a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4.

[0068] The first end of the first resistor R1 serves as the input end of the PWM control signal generation module 13. The second end of the first resistor R1 is connected to the inverting input end of the operational amplifier U1, the first end of the second resistor R2, and the first end of the third resistor R3. The non-inverting input end of the operational amplifier U1 is connected to the reference voltage Vref. The first end of the second resistor R2 is grounded. The second end of the third resistor R3 is connected to the voltage regulation control signal TV1.

[0069] The first end of the fourth resistor R4 is connected to the inverting input end of the operational amplifier U1. The second end of the fourth resistor R4 is connected to the first end of the sixth capacitor C6. The second end of the sixth capacitor C6 is connected to the non-inverting input end of the comparator U2. The inverting input end of the comparator U2 is connected to the triangular wave signal SV1. The output end of the comparator U2 is connected to the first end of the inverter U3 and serves as the first output end of the PWM control generation module 13. The second end of the inverter U3 serves as the second output end of the PWM control generation module 13.

[0070] Specifically, the reference voltage Vref provides a stable reference level for the entire control process. It is a fixed voltage value that represents a certain proportional relationship with the desired output voltage or current, depending on the circuit design and control strategy. In different application scenarios, the reference voltage Vref can be set according to the required output voltage characteristics.

[0071] The first end of the first resistor R1 serves as the input terminal to receive the feedback signal from the dynamic voltage stabilization point N2. This feedback signal is processed by a voltage division circuit composed of the second resistor R2 and the first resistor R1. The second resistor R2 is grounded, and the third resistor R3 is connected to the voltage regulation control signal TV1. By adjusting the magnitude of the voltage regulation control signal TV1, the voltage division value of the feedback signal at the inverting input terminal of the operational amplifier U1 can be changed. When the voltage division value of the feedback signal is higher than the reference voltage Vref, the operational amplifier U1 outputs a low level; when the voltage division value of the feedback signal is lower than the reference voltage Vref, the operational amplifier U1 outputs a high level. In this way, the operational amplifier U1 outputs a level signal reflecting the output state according to the comparison result between the feedback signal and the reference voltage Vref.

[0072] The triangular wave signal SV1 is a periodically varying signal, and its voltage value rises and falls linearly with time. The triangular wave signal SV1 provides a time reference and a modulation carrier for the generation of the PWM control signal. In a DC converter, the frequency of the triangular wave signal SV1 may be between several tens of kilohertz and several hundreds of kilohertz, and its amplitude is determined according to factors such as the withstand voltage of the controllable switch and the control requirements in the circuit. For example, if the withstand voltage of the controllable switch is 100V, the amplitude of the triangular wave signal SV1 may be set slightly lower than 100V to ensure that the switch tube does not bear excessive voltage stress during the modulation process.

[0073] The output signal of the operational amplifier U1 is processed by the circuit composed of the fourth resistor R4 and the sixth capacitor C6 and then input to the non-inverting input terminal of the comparator U2. At the same time, the triangular wave signal SV1 is input to the inverting input terminal of the comparator U2. When the operational amplifier U1 outputs a high level, the circuit composed of the fourth resistor R4 and the sixth capacitor C6 will perform a certain delay and filtering process on this high-level signal and then compare it with the triangular wave signal SV1. In the rising edge stage of the triangular wave signal SV1, when the voltage value of the triangular wave signal SV1 is lower than the voltage value of the processed output signal of the operational amplifier U1, the comparator U2 outputs a high level; when the voltage value of the triangular wave signal SV1 is higher than this value, the comparator U2 outputs a low level. In the falling edge stage of the triangular wave signal SV1, the situation is opposite. In this way, the comparator U2 outputs a PWM control signal with a pulse width varying with the feedback signal according to the relative magnitudes of the triangular wave signal SV and the output signal of the operational amplifier U1. By adjusting the voltage regulation control signal TV1, the duty cycle of the PWM control signal can be changed, thereby realizing the regulation of the output voltage of the DC converter. The voltage regulation control signal TV1 can be a constant voltage signal or a constant current signal.

[0074] The duty cycle of the PWM control signal directly determines the proportional relationship between the conduction time and the turn-off time of the controllable switch on the bridge arm in the DC converter. When the duty cycle increases, the conduction time of the controllable switch becomes longer, the charging time of the inductor unit increases, the stored energy increases, and the energy released to the load during the discharging stage also increases correspondingly, thus increasing the output voltage; conversely, when the duty cycle decreases, the conduction time of the controllable switch becomes shorter, the charging time of the inductor unit decreases, the stored energy decreases, and the output voltage decreases.

[0075] The entire PWM control signal generation module 13 continuously monitors the voltage of the dynamic voltage stabilization point N2 through a feedback mechanism and adjusts the duty cycle of the PWM control signal according to the comparison result with the reference voltage Vref. If the voltage of the dynamic voltage stabilization point N2 is higher than the reference voltage Vref, the feedback signal will make the output low level time of the operational amplifier U1 longer. After modulation, the duty cycle of the PWM control signal decreases, thereby reducing the voltage of the dynamic voltage stabilization point N2; if the voltage of the dynamic voltage stabilization point N2 is lower than the reference voltage Vref, the feedback signal will make the output high level time of the operational amplifier U1 longer, and the duty cycle of the PWM control signal increases, raising the voltage of the dynamic voltage stabilization point N2. In this way, the closed-loop control of the output voltage is realized, enabling the DC converter to always maintain the stability of the voltage of the dynamic voltage stabilization point N2 under different load conditions and input voltage fluctuations.

[0076] Figure 9 It is a schematic structural diagram of the ninth optional DC converter provided by the embodiment of the present invention. Figure 10It is a schematic structural diagram of the tenth optional DC converter provided by an embodiment of the present invention. Figure 11 It is a schematic structural diagram of the eleventh optional DC converter provided by an embodiment of the present invention. Refer to Figures 9 to 11 , optionally, the power supply module 11 includes one or more of a boost module 110, a buck module 120, a buck-boost module 130, and a floating voltage current source. Among them, Figure 9 The case where the power supply module 11 includes the boost module 110 is schematically shown. Figure 10 The case where the power supply module 11 includes the buck module 120 is schematically shown. Figure 11 The case where the power supply module 11 includes the buck-boost module 130 is schematically shown.

[0077] Exemplarily, refer to Figure 9 , the boost module 110 includes a first DC power supply V1, a tenth inductor L10, a third transistor T3, and a fourth transistor T4. The first end of the first DC power supply V1 is connected to the first end of the tenth inductor L10. The first pole of the third transistor T3 is connected to the first pole of the first controllable switch T11. The second pole of the third transistor T3 is connected to the first pole of the fourth transistor T4 and the second end of the tenth inductor L10. The second pole of the fourth transistor T4 is connected to the second pole of the second controllable switch T21 and the second end of the first DC power supply V1.

[0078] Exemplarily, refer to Figure 10 , the buck module 120 includes a second DC power supply V2, a fifth transistor T5, and a sixth transistor T6, and further includes an LC filter circuit composed of a third inductor L3 and a first capacitor C1. The first end of the second DC power supply V2 is connected to the first pole of the fifth transistor T5 and the first pole of the first controllable switch T11. The second pole of the fifth transistor T5 is connected to the first pole of the sixth transistor T6 at a second node. The second node is connected to the first end of the third inductor L3. The second end of the third inductor L3 is connected to the first end of the first capacitor C1. The second pole of the sixth transistor T6 is connected to the second pole of the second controllable switch T21 and the second end of the second DC power supply V2. The above buck module 120 can provide a stable output voltage. The output point of the output voltage is located between the third inductor L3 and the first capacitor C1. As can be seen from the above, the above output point is used as the first end of the power supply module 11, satisfying that the first end of the first capacitor C1 is connected to the first end of the power supply module. At the same time, the magnitude of the output voltage can be adjusted within the output voltage range of the second DC power supply V2.

[0079] Exemplarily, refer to Figure 11, the buck-boost module 130 includes a third DC power supply V3, a fourth inductor L4, a seventh transistor T7, an eighth transistor T8, a ninth transistor T9, and a tenth transistor T10. The first pole of the seventh transistor T7 is connected to the first end of the third DC power supply V3. The second pole of the seventh transistor T7 is connected to the first end of the fourth inductor L4 and the first pole of the eighth transistor T8. The second pole of the eighth transistor T8 is connected to the second end of the third DC power supply V3. The first pole of the ninth transistor T9 is connected to the first pole of the first controllable switch T11. The second pole of the ninth transistor T9 is connected to the first pole of the tenth transistor T10 and the second end of the fourth inductor L4. The second pole of the tenth transistor T10 is connected to the second pole of the second controllable switch T21 and the second end of the third DC power supply V3.

[0080] After combining the boost, buck, or buck-boost topology in the front stage, the sum of the above-mentioned multiple series voltages can also achieve step-up or step-down, rather than being fixed at the power supply voltage.

[0081] Figure 12 It is a schematic structural diagram of the twelfth optional DC converter provided by the embodiments of the present invention. Refer to Figure 12 , the power supply module 11 includes a voltage conversion unit 111, an isolation unit 112, and a rectification unit 113.

[0082] The voltage conversion unit 111 accesses the second DC voltage Vin2 and is used to convert the second DC voltage Vin2 into an AC voltage. The isolation unit 112 is respectively connected to the voltage conversion unit 111 and the rectification unit 113 and is used to isolate the voltage conversion unit 111 and the rectification unit 113. The rectification unit 113 is used to convert the AC voltage into the first DC voltage Vin1. Connecting an isolated and regulated power supply at the input end of the DC converter can ensure the isolation and regulation of multiple outputs; it can also be bidirectionally isolated.

[0083] Based on the same inventive concept, the present invention provides a power amplifier system, Figure 13 It is a schematic structural diagram of a power amplifier system provided by the embodiments of the present invention. Figure 14 It is a schematic structural diagram of another power amplifier system provided by the embodiments of the present invention. As Figure 13 and Figure 14 shown, the power amplifier system includes the DC converter 1 provided by any embodiment of the present invention, and also includes a CLASS D type power amplifier 21 or a CLASS G type power amplifier 22.

[0084] When the DC converter outputs at least one positive and negative adjustable voltage, the DC converter 1 is used to supply power to the Class D type power amplifier 21; when the number N of bridge arms in the DC converter 1 is greater than or equal to 3, the number M of inductor units is greater than or equal to 3, and the DC converter 1 includes a fourth capacitor C4 and a fifth capacitor C5, the DC converter 1 is used to simultaneously output at least two positive voltages and at least two negative voltages to supply power to the Class G type power amplifier 22.

[0085] Exemplarily, Figure 13 When the DC converter 1 is used as a power supply for the Class D type power amplifier 21, the positive and negative dual power supply also has the ability of bidirectional power transmission. When the Class D outputs positive power, the positive power rail discharges the load through the blue current path. However, at the same time, the negative power rail absorbs power through the red current path. When the negative power rail outputs negative power, due to the bidirectional ability of the DC converter of the present invention, the negative power will be transmitted to the input side. At the same time, the power output by the first capacitor C1 is greater than the power fed back by the second capacitor C2. Therefore, the power supply module 11 cannot sense the fed-back energy, preventing the negative rail power supply voltage from rebounding too much and causing faults or error reports. The power rail is switched by switch gating or automatic gating through circuit competition. The existing method is to provide multi-rail power by connecting multiple DC-DCs in series, and the existing method requires multiple isolations and is relatively complex.

[0086] For example Figure 14 The DC converter 1 shown can supply power to the Class G type power amplifier 22 and provide a series of multi-rail power supplies. The input terminal Vin of the Class G type power amplifier 22 is used to connect to an audio signal source, and the output terminal Vout is used to connect to a load such as a speaker. Specifically, the input terminal Vin of the Class G type power amplifier 22 is responsible for receiving weak electrical signals from various audio signal sources, which can be a CD player, a computer, a mobile phone, a mixer, a microphone, etc. The input signals are usually voltage signals containing audio information, such as analog audio signals or analog signals after digital-to-analog conversion of digital audio signals, providing the original data for the subsequent amplification process of the power amplifier. The output terminal Vout of the Class G type power amplifier 22 outputs the audio signal processed and amplified by the internal amplification circuit of the power amplifier, providing sufficient power drive for loads such as speakers, causing the diaphragm of the speaker to vibrate, thereby converting the electrical signal into a sound signal so that people can hear the amplified sound.

[0087] Through the above embodiments, the application of the voltage-current source in an Automatic Test Equipment (ATE) can be simplified. In the application of ATE, a power supply that is floating, multi-channel, and adjustable in both positive and negative directions needs to be provided. Specifically, the "multi-channel" mentioned above is because test chips generally have high requirements for test efficiency, and multiple chips often need to be tested simultaneously, so multiple channels are required. The "floating" mentioned above is because, in addition to multiple channels, the circuits also need to be independently wired without affecting each other and be isolated from each other, so floating is required. In summary, parallel testing requires both multiple channels and floating. In addition, "multi-channel" is generally applied to situations where complex testing is required, such as testing complex chips. The number of pins and chip testing are relatively complex, and multiple-channel sources need to be tested together. "Floating" is generally applied to situations where series and parallel connections are required inside the output source (voltage source or current source), which can improve the voltage or current capacity and the output power coverage ability to meet greater power test requirements. Through the above embodiments, multi-channel parallel testing can be achieved, improving the test efficiency. For example, for the testing of complex chips such as analog-to-digital converters (ADCs) or digital-to-analog converters (DACs), it is also possible to test complex chips or large-scale integrated circuits, which have complex functions and require parallel testing, or include mixed-signal testing, such as the testing of system-on-chip (SOC), microcontroller unit (MCU), and field-programmable gate array (FPGA).

[0088] Figure 15 is a schematic structural diagram of a battery system provided by an embodiment of the present invention. As Figure 15 shown, the battery system includes the DC converter 1 provided by any embodiment of the present invention, and further includes a plurality of serially connected batteries 3. When the number N of bridge arms in the DC converter 1 is greater than or equal to 3, the number M of inductor units is greater than or equal to 3, and the DC converter 1 includes a fourth capacitor C4 and a fifth capacitor C5, the DC converter 1 includes multiple sets of output terminals, and each set of output terminals is connected to a battery 3 to charge the battery 3.

[0089] Now, with the popularization of new energy vehicles, the application of large-scale series and parallel connections of batteries is increasing. In a circuit that forms a high-voltage output voltage source by serially connecting multiple low-voltage large batteries, battery charging is involved. Figure 16 is a schematic structural diagram of a battery system provided by the related art. As Figure 16 shown, the existing battery system requires a battery management system 4 (Battery Management System, BMS) to control the charging voltage of each battery 3 to prevent overcharging and over-discharging of the battery 3. And if Figure 6This series multi-channel voltage output structure can significantly reduce the pressure on BMS management. Since each series voltage source has a closed-loop voltage feedback, there will be no voltage division problem caused by inconsistent battery internal resistances. Because it directly uses multi-channel voltage sources for charging instead of a total voltage for charging, the balance problem of series voltage division can be solved.

[0090] The above specific embodiments do not constitute a limitation to the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A DC converter, characterized in that: include: A power supply module, used for providing a first DC voltage; N bridge arms, each bridge arm comprising a first controllable switch and a second controllable switch that are alternately turned on, a first end of the first controllable switch being connected to a first end of the power supply module, a second end of the first controllable switch and a first end of the second controllable switch being connected to a first node, a second end of the second controllable switch being connected to a second end of the power supply module, and control ends of the first controllable switch and the second controllable switch being both connected to a PWM control signal; N is a positive integer; M inductance units and N dynamic voltage stabilization points, the dynamic voltage stabilization points are arranged in one-to-one correspondence with the first nodes, the first ends of the inductance units are connected to the first nodes in correspondence, and the second ends of the inductance units are connected to the dynamic voltage stabilization points in correspondence; M is a positive integer less than or equal to N; When N=1, the DC converter further includes a first capacitor and a second capacitor, the first end of the first capacitor is connected to the first end of the power supply module, the second end of the first capacitor and the first end of the second capacitor are connected to the dynamic voltage stabilization point, and the second end of the second capacitor is connected to the second end of the power supply module to form two output voltages connected in series; or, When N is greater than or equal to 2, the DC converter includes a plurality of third capacitors, and the third capacitors are respectively arranged between adjacent N dynamic voltage stabilization points to form at most N-1 series output voltages; wherein the output voltage includes at least one positive voltage and at least one negative voltage output simultaneously, or includes at least one positive and negative adjustable voltage.

2. The DC converter according to claim 1, characterized in that: When N is greater than or equal to 2, the DC converter further includes a fourth capacitor and / or a fifth capacitor; The first end of the fourth capacitor is connected to the first end of the power supply module, and the second end of the fourth capacitor is connected to the dynamic voltage stabilization point adjacent to the first end of the power supply module; The first end of the fifth capacitor is connected to the second end of the power supply module, and the second end of the fifth capacitor is connected to the dynamic voltage stabilization point adjacent to the second end of the power supply module.

3. The DC converter according to claim 1, characterized in that: It also includes N PWM control signal generating modules, the input end of the PWM control signal generating module is connected to the corresponding dynamic voltage stabilization point, the first output end of the PWM control signal generating module is connected to the corresponding first controllable switch, and the second output end of the PWM control signal generating module is connected to the control end of the corresponding second controllable switch, for generating the PWM control signal.

4. The DC converter according to claim 3, characterized in that: The duty cycles of the PWM control signals generated by different PWM control signal generating modules are different.

5. The DC converter according to claim 3, characterized in that: The PWM control signal generating module includes an operational amplifier, a comparator, an inverter, a sixth capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor; The first end of the first resistor is used as the input end of the PWM control signal generating module, the second end of the first resistor is connected to the inverting input end of the operational amplifier, the first end of the second resistor and the first end of the third resistor, the non-inverting input end of the operational amplifier is connected to the reference voltage, the second end of the second resistor is grounded, and the second end of the third resistor is connected to the voltage regulation control signal; The first end of the fourth resistor is connected to the inverting input end of the operational amplifier, the second end of the fourth resistor is connected to the first end of the sixth capacitor, the second end of the sixth capacitor is connected to the non-inverting input end of the comparator, the inverting input end of the comparator is connected to a triangular wave signal, the output end of the comparator is connected to the first end of the inverter and serves as the first output end of the PWM control generation module, and the second end of the inverter serves as the second output end of the PWM control generation module.

6. The DC converter according to claim 1, characterized in that: The power supply module includes one or more of a boost module, a buck module, a buck-boost module and a floating voltage and current source.

7. The DC converter according to claim 1, characterized in that: The power supply module includes a voltage conversion unit, an isolation unit and a rectification unit; The voltage conversion unit is connected to a second DC voltage and is used to convert the second DC voltage into an AC voltage; The isolation unit is connected to the voltage conversion unit and the rectification unit respectively, and is used to isolate the voltage conversion unit from the rectification unit; The rectifying unit is used for converting the AC voltage into the first DC voltage.

8. The DC converter according to claim 1, characterized in that: The voltage values ​​of the positive voltage and the negative voltage are associated with the duty cycle of the PWM control signal connected to the control ends of the first controllable switch and the second controllable switch on the corresponding bridge arm.

9. A power amplifier system, characterized in that: A DC converter according to any one of claims 1 to 8, further comprising a CLASSD type power amplifier or a CLASS G type power amplifier; When the DC converter outputs at least one positive and negative adjustable voltage, the DC converter is used to power the CLASSD type power amplifier; When the number N of bridge arms in the DC converter is greater than or equal to 3, the number M of the inductance units is greater than or equal to 3, and the DC converter includes a fourth capacitor and a fifth capacitor, the DC converter is used to simultaneously output at least two positive voltages and at least two negative voltages to power the Class G power amplifier.

10. A battery system, characterized in that: A DC converter according to any one of claims 1 to 8, further comprising a plurality of batteries connected in series; When the number N of bridge arms in the DC converter is greater than or equal to 3, the number M of the inductor units is greater than or equal to 3, and the DC converter includes a fourth capacitor and a fifth capacitor, the DC converter includes multiple groups of output terminals, each group of output terminals is connected to one of the batteries to charge the battery.

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