Non-isolated power supply circuit and non-isolated power supply

Abstract

The utility model embodiment discloses a non-isolated power supply circuit and a non-isolated power supply, the circuit comprising: a conversion module including an isolated power supply, the input end of the conversion module is connected to a first voltage source, and the second output end of the conversion module is connected to a negative voltage reference ground; the conversion module converts a first voltage output by the first voltage source into a second voltage through the isolated power supply; a control module, the input end of the control module is connected to the first output end of the conversion module, and the control module outputs a driving signal in response to the second voltage; a conversion module, the power input end of the conversion module is connected to a third voltage source, and the signal input end of the conversion module is connected to the output end of the control module; the conversion module converts a third voltage output by the third voltage source into a first negative voltage in response to the driving signal. The utility model embodiment avoids the problem of high power consumption of the control module due to internal power supply by setting the conversion module to power the control module, improves power supply efficiency, and reduces the temperature rise of the power supply.

Description

Technical Field

[0001] The embodiments of the utility model relate to the field of non-isolated power supplies, and in particular to a non-isolated power supply circuit and a non-isolated power supply. Background Art

[0002] In the current negative voltage output non-isolated power supply technology, the system power supply of the control chip and the power supply of the power circuit are generated inside the control chip. A low voltage dropout voltage regulator circuit is set inside the control chip to reduce the input voltage to the power supply voltage required by the control chip to meet its own power supply needs, thereby maintaining the normal operation of the power supply system.

[0003] However, when the input voltage is high, since the control chip requires a low power supply voltage, there is a large voltage difference between the input voltage and the output voltage of the low-voltage difference voltage regulator circuit, which will cause the control chip to consume more power and generate more heat, thereby reducing the efficiency of the power supply and increasing the temperature rise of the power supply. Utility Model Content

[0004] The main technical problem solved by the embodiments of the utility model is to provide a non-isolated power supply circuit and a non-isolated power supply, which can solve the problem caused by the high power consumption of the control chip.

[0005] In order to solve the above technical problems, a technical solution adopted by the utility model is: to provide a non-isolated power supply circuit, including: a conversion module including an isolated power supply, the input end of the conversion module is connected to a first voltage source, and the second output end of the conversion module is connected to a negative voltage reference ground; the conversion module converts a first voltage output by the first voltage source into a second voltage through the isolated power supply, and the reference ground of the second voltage is the negative voltage reference ground; a control module, the input end of the control module is connected to the first output end of the conversion module, and the control module outputs a driving signal in response to the second voltage; a conversion module, the power input end of the conversion module is connected to a third voltage source, and the signal input end of the conversion module is connected to the output end of the control module; the conversion module converts a third voltage output by the third voltage source into a first negative voltage in response to the driving signal.

[0006] In some embodiments, the conversion module includes an isolated power supply U1 and a voltage regulator U2, wherein the first input terminal of the isolated power supply U1 is connected to the positive output terminal of the first voltage source, and the second input terminal of the isolated power supply U1 is connected to the negative output terminal of the first voltage source; the first output terminal of the isolated power supply U1 is connected to the input terminal of the voltage regulator U2, the second output terminal of the isolated power supply U1 is connected to the negative voltage reference ground, and the output terminal of the voltage regulator U2 is connected to the input terminal of the control module.

[0007] In some embodiments, the conversion module also includes a capacitor C1 and a capacitor C2, the first end of the capacitor C1 is connected to the first output end of the isolated power supply, and the second end of the capacitor C1 is connected to the second output end of the isolated power supply U1; the first end of the capacitor C2 is connected to the output end of the regulator U2, and the second end of the capacitor C2 is connected to the second output end of the isolated power supply U1.

[0008] In some embodiments, the conversion module includes a switch tube M1, an inductor L1, a diode D1 and a capacitor C3, the first end of the switch tube M1 is connected to the positive output end of the third voltage source, the second end of the switch tube M1 is connected to the first end of the inductor L1 and the cathode of the diode D1, and the controlled end of the switch tube M1 is connected to the output end of the control module; the negative output end of the third voltage source, the second end of the inductor L1 and the second end of the capacitor C3 are connected to the zero potential reference ground GND, and the anode of the diode D1 is connected to the first end of the capacitor C3 as the output end of the first negative voltage.

[0009] In some embodiments, the isolated power supply is an isolated DC-DC power supply.

[0010] In some embodiments, the control module includes a control chip.

[0011] In some embodiments, the regulator U2 is a low dropout linear regulator.

[0012] In some embodiments, types of the switch transistor M1 include bipolar transistors, metal-oxide semiconductor field effect transistors and insulated gate bipolar transistors.

[0013] In some embodiments, a level of the first negative voltage is equal to a level of the negative voltage reference ground.

[0014] In order to solve the above technical problems, another technical solution adopted by the present invention is: to provide a non-isolated power supply, including: a non-isolated power supply circuit as described above.

[0015] The beneficial effects of the embodiment of the utility model are: different from the prior art, the embodiment of the utility model avoids the problem of high power consumption of the control module due to internal power supply by setting a conversion module to power the control module, improves power supply efficiency, and reduces the temperature rise of the power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of an existing non-isolated power supply circuit;

[0017] Figure 2 It is a structural schematic diagram of a non-isolated power supply circuit provided by an embodiment of the utility model;

[0018] Figure 3 This is a circuit structure diagram of a conversion module provided by an embodiment of the utility model;

[0019] Figure 4 It is a circuit structure diagram of a conversion module provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0020] In order to facilitate the understanding of the utility model, the utility model is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on the other element, or there can be one or more centered elements therebetween. When an element is described as "connected to" another element, it can be directly connected to the other element, or there can be one or more centered elements therebetween. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this specification are for illustrative purposes only.

[0021] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by technicians in the technical field of the present invention. The terms used in this specification are only for the purpose of describing specific embodiments and are not used to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more related listed items.

[0022] Figure 1 A non-isolated power supply circuit is shown, which includes a control module 120 and a conversion module 130, the output end of the third voltage source 30 is connected to the power input end of the conversion module 130 and the input end of the control module 120, the output end of the control module 120 is connected to the signal input end of the conversion module 130, and the reference ground AGND of the control module 120 is a negative voltage reference ground.

[0023] The control module 120 includes a low-dropout regulator (LDO) circuit. The control module 120 converts the third voltage input by the third voltage source 30 into a second voltage through the low-dropout regulator circuit to power itself, and then outputs a driving signal to the conversion module 130 to drive the power device in the conversion module 130.

[0024] When the third voltage input by the third voltage source 30 is relatively large, since the power supply voltage required by the control module 120 itself is relatively low, there is a large voltage difference between the second voltage and the third voltage, resulting in greater power loss and increased heat generation of the control module 120, which in turn leads to reduced efficiency of the non-isolated power supply and increased temperature rise.

[0025] To solve the above problems, the present application provides a non-isolated power supply circuit, the structural diagram of which is shown in FIG. Figure 2 As shown, the non-isolated power supply circuit includes a conversion module 110 , a control module 120 and a transformation module 130 .

[0026] The specific connection relationship is: the input end of the conversion module 110 is connected to the first voltage source 20, the second output end of the conversion module 110 is connected to the negative voltage reference ground AGND, the input end of the control module 120 is connected to the first output end of the conversion module 110, the power input end of the conversion module 130 is connected to the third voltage source 30, and the signal input end of the conversion module 130 is connected to the output end of the control module 120.

[0027] In the embodiment of the present application, the conversion module 110 includes an isolated power supply, and the conversion module converts the first voltage output by the first voltage source into a second voltage through the isolated power supply. It should be noted that the reference ground of the second voltage is the negative voltage reference ground AGND.

[0028] The control module 120 outputs a driving signal in response to the second voltage; the conversion module 130 converts the third voltage output by the third voltage source 30 into a first negative voltage in response to the driving signal, and the first negative voltage is equal to the level of the negative voltage reference ground AGND.

[0029] In the embodiment of the present application, the control module 120 includes a control chip.

[0030] In some embodiments of the present application, a conversion module is provided, whose circuit structure is as follows: Figure 3 As shown, the device includes an isolated power supply U1, a voltage regulator U2, a capacitor C1 and a capacitor C2.

[0031] Among them, the first input end of the isolated power supply U1 is connected to the positive output end of the first voltage source 20, and the second input end of the isolated power supply U1 is connected to the negative output end of the first voltage source 20; the first output end of the isolated power supply U1 is connected to the input end of the voltage regulator U2, the second output end of the isolated power supply U1 is connected to the negative voltage reference ground, and the output end of the voltage regulator U2 is connected to the input end of the control module.

[0032] The first end of capacitor C1 is connected to the first output end of the isolated power supply, and the second end of capacitor C1 is connected to the second output end of the isolated power supply U1; the first end of capacitor C2 is connected to the output end of regulator U2, and the second end of capacitor C2 is connected to the second output end of the isolated power supply U1.

[0033] In the embodiment of the present application, the voltage regulator U2 is a low voltage dropout linear regulator, and the isolated power supply U1 is an isolated DC-DC power supply.

[0034] The isolated power supply U1 includes an isolation element, such as a transformer, an optical coupler, or a capacitive coupler, which converts the input voltage into an isolated output voltage. Specifically, the second output terminal of the isolated power supply U1 is connected to a negative voltage reference ground AGND. The negative voltage reference ground AGND is the reference point of the output voltage of the isolated power supply U1, which is isolated from the reference ground of the input terminal.

[0035] The input end of the isolated power supply U1 receives an input voltage, namely, a first voltage, and the reference ground of the first voltage is a zero voltage reference ground. Therefore, the isolated power supply U1 converts the input first voltage with the zero voltage reference ground as the reference ground into a second voltage VCC with the negative voltage reference ground AGND as the reference ground through the isolation element to power the control module 120.

[0036] In some embodiments of the present application, a conversion module is provided, whose circuit structure is as follows: Figure 4 As shown, the conversion module includes a switch tube M1, an inductor L1, a diode D1 and a capacitor C3.

[0037] The first end of the switch tube M1 is connected to the positive output end of the third voltage source 30 , the second end of the switch tube M1 is connected to the first end of the inductor L1 and the cathode of the diode D1 , and the controlled end of the switch tube M1 is connected to the output end of the control module 120 .

[0038] The negative output terminal of the third voltage source 30, the second terminal of the inductor L1 and the second terminal of the capacitor C3 are connected to the zero potential reference ground GND, and the anode of the diode D1 is connected to the first terminal of the capacitor C3 as the output terminal of the first negative voltage -Vo.

[0039] In the embodiment of the present application, types of the switch tube M1 include bipolar junction transistor (BJT), metal-oxide semiconductor field effect transistor (MOS-FET) and insulated-gate bipolar transistor (IGBT).

[0040] When the switch tube M1 is turned on, the third voltage is applied to the inductor L1, and the inductor L1 stores energy. The energy of the output load comes from the capacitor C3, because the capacitor C3 can store charge and provide energy to the load when the switch tube M1 is turned on.

[0041] When the switch tube M1 is turned off, the current of the inductor L1 continues to flow through the diode D1 and continues to flow through the load. At the same time, the inductor current also charges the capacitor C3 to store energy and provide energy for the next switching cycle.

[0042] Specifically, when the switch tube M1 is turned on, the third voltage is added to the inductor L1, and the current flows from the positive electrode of the third voltage source 30 into the inductor L1 to store energy in the inductor L1. When the switch tube M1 is turned off, since the current in the inductor L1 cannot immediately become zero, the reverse electromotive force generated by the inductor L1 continues to drive the current to flow, and the inductor current flows through the diode D1 to provide energy to the load and charge the capacitor C3. As the voltage of the capacitor C3 rises, the current in the inductor L1 gradually decreases. At this time, the voltage at the first terminal of the capacitor C3 is lower than the zero potential reference ground GND of the third voltage, forming a negative voltage output. When the switch tube M1 is turned on again, the third voltage is added to the inductor L1, and the current flows into the inductor L1 to store energy in the inductor, and the above process is repeated.

[0043] Different from the prior art, the embodiment of the utility model provides a conversion module to power the control module, thereby avoiding the problem of high power consumption of the control module due to internal power supply, improving power supply efficiency, and reducing the temperature rise of the power supply.

[0044] Based on the non-isolated power supply circuit provided in the above embodiment, the embodiment of the present application further provides a non-isolated power supply, which includes the non-isolated power supply circuit provided in the above embodiment.

[0045] It should be noted that the preferred embodiments of the utility model are given in the specification and drawings of the utility model, but the utility model can be implemented in many different forms and is not limited to the embodiments described in the specification. These embodiments are not used as additional restrictions on the content of the utility model. The purpose of providing these embodiments is to make the understanding of the disclosure of the utility model more thorough and comprehensive. In addition, the above-mentioned technical features continue to be combined with each other to form various embodiments not listed above, which are all regarded as the scope of the description of the utility model; further, for ordinary technicians in this field, they can be improved or transformed according to the above description, and all these improvements and transformations should belong to the scope of protection of the claims attached to the utility model.

Claims

1. A non-isolated power supply circuit, characterized in that: include: A conversion module comprising an isolated power supply, wherein an input end of the conversion module is connected to a first voltage source, and a second output end of the conversion module is connected to a negative voltage reference ground; The conversion module converts the first voltage output by the first voltage source into a second voltage through the isolated power supply, and the reference ground of the second voltage is the negative voltage reference ground; a control module, wherein an input end of the control module is connected to a first output end of the conversion module, and the control module outputs a driving signal in response to the second voltage; A conversion module, wherein the power input terminal of the conversion module is connected to a third voltage source, and the signal input terminal of the conversion module is connected to the output terminal of the control module; The conversion module converts the third voltage output by the third voltage source into a first negative voltage in response to the driving signal.

2. The circuit according to claim 1, characterized in that The conversion module includes an isolated power supply U1 and a voltage regulator U2. The first input terminal of the isolated power supply U1 is connected to the positive output terminal of the first voltage source, and the second input terminal of the isolated power supply U1 is connected to the negative output terminal of the first voltage source; The first output end of the isolated power supply U1 is connected to the input end of the voltage regulator U2, the second output end of the isolated power supply U1 is connected to the negative voltage reference ground, and the output end of the voltage regulator U2 is connected to the input end of the control module.

3. The circuit according to claim 2, characterized in that The conversion module also includes capacitor C1 and capacitor C2. The first end of the capacitor C1 is connected to the first output end of the isolated power supply, and the second end of the capacitor C1 is connected to the second output end of the isolated power supply U1; A first end of the capacitor C2 is connected to an output end of the voltage regulator U2 , and a second end of the capacitor C2 is connected to a second output end of the isolated power supply U1 .

4. The circuit according to claim 1, characterized in that The conversion module includes a switch tube M1, an inductor L1, a diode D1 and a capacitor C3. The first end of the switch tube M1 is connected to the positive output end of the third voltage source, the second end of the switch tube M1 is connected to the first end of the inductor L1 and the cathode of the diode D1, and the controlled end of the switch tube M1 is connected to the output end of the control module; The negative output end of the third voltage source, the second end of the inductor L1 and the second end of the capacitor C3 are connected to the zero potential reference ground GND, and the anode of the diode D1 is connected to the first end of the capacitor C3 as the output end of the first negative voltage.

5. The circuit according to claim 1, characterized in that The isolated power supply is an isolated DC-DC power supply.

6. The circuit according to claim 1, characterized in that The control module includes a control chip.

7. The circuit according to claim 2, characterized in that The voltage regulator U2 is a low voltage dropout linear regulator.

8. The circuit according to claim 4, characterized in that The types of the switch tube M1 include bipolar transistors, metal-oxide semiconductor field effect transistors and insulated gate bipolar transistors.

9. The circuit according to any one of claims 1 to 8, characterized in that: The level of the first negative voltage is equal to the level of the negative voltage reference ground.

10. A non-isolated power supply, characterized in that: include: A non-isolated power supply circuit as claimed in any one of claims 1 to 9.

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