A novel isolation-free conversion circuit
By using a simplified component configuration with a non-isolated conversion circuit, the high cost of traditional electronic equipment grounding technology is solved, achieving efficient and low-cost power conversion. It is suitable for high-frequency switching scenarios and cost-sensitive industrial control and new energy equipment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- XIAMEN COSTCO ELECTRONIC IND CO LTD
- Filing Date
- 2025-06-19
- Publication Date
- 2026-06-26
AI Technical Summary
Traditional electronic devices have high grounding technology costs, and their complex circuit structures significantly increase product costs, making it difficult to balance conversion efficiency and cost while ensuring safety performance.
It adopts a non-isolation conversion circuit, including a first inductor, a second inductor, a capacitor, a diode group and a MOSFET, and achieves high-efficiency power conversion through a simplified component configuration, eliminating the need for isolation devices such as transformers or optocouplers, and supporting offline operation mode without filtered DC input.
Significantly reduces hardware costs, improves conversion efficiency, reduces noise characteristics, adapts to high-frequency switching scenarios, and is suitable for cost- and reliability-sensitive industrial control and new energy equipment.
Smart Images
Figure CN224418692U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electronic equipment technology, and in particular to a novel non-isolated switching circuit. Background Technology
[0002] With the rapid development of the economy and society, market competition is intensifying, and the application scenarios of various electronic devices are constantly expanding. To ensure the safety of electronic devices, their grounding technology is also continuously iterating and upgrading. At the same time, customers' functional requirements for electronic devices are increasing, forcing circuit design to develop towards higher efficiency and precision. While complex circuit structures can optimize performance, they often lead to a significant increase in product costs.
[0003] Therefore, there is an urgent need in related technologies for a new type of non-isolated conversion circuit that can balance conversion efficiency and product cost while ensuring safety performance, thus providing a more competitive power solution for modern electronic devices. Utility Model Content
[0004] This application provides a novel non-isolation switching circuit to solve the problem of high cost in traditional electronic device grounding technology.
[0005] Therefore, in a first aspect, embodiments of this application provide a novel non-isolated switching circuit, characterized in that it includes: a first inductor, a second inductor, a first capacitor, a second capacitor, a diode group, a first MOSFET and a second MOSFET, wherein the diode group includes a first diode, a second diode, a third diode and a fourth diode;
[0006] One end of the first inductor is connected to the positive input terminal, and the other end is connected to the drain of the first MOSFET, the positive terminal of the first diode, and the negative terminal of the third diode. The source of the first MOSFET is connected to the positive terminal of the second diode and one end of the first capacitor. The other end of the first capacitor is connected to the drain of the second MOSFET. The source of the second MOSFET is connected to the negative input terminal. The positive terminal of the third diode is connected to one end of the second inductor and the negative terminal of the fourth diode. The other end of the second inductor is connected to the positive output terminal and the positive terminal of the second capacitor. The other end of the second capacitor C2 is connected to the negative output terminal.
[0007] According to an embodiment of this application, a novel non-isolated switching circuit is provided. The circuit includes: a first inductor, a second inductor, a first capacitor, a second capacitor, a diode group, a first MOSFET and a second MOSFET. The diode group includes a first diode, a second diode, a third diode, and a fourth diode. One end of the first inductor is connected to the positive input terminal, and the other end is connected to the drain of the first MOSFET, the positive terminal of the first diode, and the negative terminal of the third diode. The source of the first MOSFET is connected to the positive terminal of the second diode and one end of the first capacitor. The other end of the first capacitor is connected to the drain of the second MOSFET. The source of the second MOSFET is connected to the negative input terminal. The positive terminal of the third diode is connected to one end of the second inductor and the negative terminal of the fourth diode. The other end of the second inductor is connected to the positive output terminal and the positive terminal of the second capacitor. The other end of the second capacitor C2 is connected to the negative output terminal. The non-isolation conversion circuit provided in this application embodiment does not use isolation devices (such as transformers, optocouplers, etc.) in its circuit structure. This circuit is applied to DC-DC power supplies. The advantage of this circuit is that it drives the circuit with the fewest components, thereby improving the efficiency of the entire product and reducing the cost. Attached Figure Description
[0008] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without creative effort. In addition, in the drawings, the same parts use the same reference numerals, and the drawings are not drawn to scale.
[0009] Figure 1 This is a schematic diagram of a novel non-isolation switching circuit provided in a specific embodiment of this application. Detailed Implementation
[0010] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0011] Figure 1 A schematic diagram of a novel non-isolation switching circuit provided in a specific embodiment of this application; see reference. Figure 1As shown, this embodiment provides a novel non-isolated switching circuit, including: a first inductor L1, a second inductor L2, a first capacitor C1, a second capacitor C2, a diode group, a first MOSFET Q1 and a second MOSFET Q2, wherein the diode group includes: a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4.
[0012] One end of the first inductor L1 is connected to the positive voltage input terminal Vin+, and the other end is connected to the drain of the first MOSFET Q1, the anode of the first diode D1, and the cathode of the third diode D3. The source terminal of the first MOSFET Q1 is connected to the anode of the second diode D2 and one end of the first capacitor C1. The other end of the first capacitor C1 is connected to the drain of the second MOSFET Q2. The source terminal of the second MOSFET Q2 is connected to the negative input terminal Vin-. The anode of the third diode D3 is connected to one end of the second inductor L2 and the cathode of the fourth diode D4. The other end of the second inductor L2 is connected to the positive output terminal Vout+ and the positive terminal of the second capacitor C2. The other end of the second capacitor C2 is connected to the negative output terminal Vout-.
[0013] As a high-efficiency power conversion solution, the non-isolated conversion circuit has the core advantage of achieving driving function through extremely simple component configuration. While improving the overall product efficiency, it significantly reduces hardware costs and provides a new path for high-performance power solutions. The novel non-isolated conversion circuit provided in this solution has the advantages of high conversion efficiency and low cost.
[0014] Refer to the following again Figure 1 The working principle of a novel non-isolated line switching circuit provided in this application embodiment will be described in detail below:
[0015] The specific circuit operation principle of the first and second inductors L1 and L2, the first and second MOSFETs Q1 and Q2, the first to third diodes D1, D2 and D3, and the first and second capacitors C1 and C2 is as follows: When the first MOSFET Q1 and the second MOSFET Q2 are in the off state, the input current Iin flows through L1, D1, and C1 to the negative terminal. Therefore, the current charges the first capacitor C1. Since the first diode D1 and the second diode D2 are both in the conducting state, the potential across the first capacitor C1 is approximately Vin. Since the third diode D3 is in the reverse bias state, no current flows to the output terminal of the converter. When the first capacitor C1 continues to charge, the current flowing through the first inductor L1 will decrease linearly. When the first MOSFET Q1 and the second MOSFET Q2 are in the conducting state, the first diode D1 and the second diode D2 will be in the reverse bias state, thus suppressing any current flowing to the input terminal. In this state, the first capacitor C1 acts as if it's connected to the converter's output. Due to its charging principle, the third diode D3 will be forward biased, so the output current flows through L2, D3, Q1, C1, and Q2. When Q1 and Q2 are both off, the voltage across the first inductor L1 is equivalent to the sum of Vin and Vc. When Q1 and Q2 turn on, the current that was previously decreasing through the first inductor L1 will now increase linearly, storing new energy in the first inductor L1. In the next cycle, when Q1 and Q2 are turned off, the energy stored in L1 will begin charging capacitor C1 through diodes D1 and D2. The inductor L1 will cause a change in the voltage across capacitor C1, which is inversely proportional to the conduction period of Q1 and Q2. Simultaneously, diode D3 will become reverse biased, and the output current continues to flow from diode D4 to the output terminal, filtered by C2, and then to Vout.
[0016] This solution provides a novel non-isolated switching circuit that employs a non-drive current design at both the input and output terminals, significantly reducing conducted and radiated noise, making it particularly suitable for high-frequency switching scenarios. In practical applications, this circuit supports offline operation with unfiltered DC input, eliminating the need for capacitors used in traditional circuits to store input energy, thus optimizing development costs. Furthermore, it offers the following technical advantages:
[0017] Low noise characteristics: The non-drive current architecture suppresses conducted and radiated interference generated during high-frequency switching in principle, providing a solution for scenarios with high electromagnetic compatibility requirements.
[0018] High-frequency adaptability: It breaks through the noise bottleneck of traditional circuits at high frequencies and can operate stably at higher switching frequencies, adapting to the miniaturization and high efficiency requirements of modern power electronic devices.
[0019] Cost-optimized design: Eliminating the input energy storage capacitor not only reduces the number of components and procurement costs, but also saves circuit board space, simplifies assembly processes, and improves the economics of mass production.
[0020] Offline application expansion: Supports offline working mode with unfiltered DC input, broadening the circuit's applicability in scenarios such as industrial control and new energy equipment, and is especially suitable for end applications that are sensitive to cost and reliability.
[0021] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0022] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.
Claims
1. A novel non-isolation switching circuit, characterized in that, include: The system comprises a first inductor, a second inductor, a first capacitor, a second capacitor, a diode group, a first MOSFET and a second MOSFET, wherein the diode group includes a first diode, a second diode, a third diode and a fourth diode; One end of the first inductor is connected to the positive input terminal, and the other end is connected to the drain of the first MOSFET, the positive terminal of the first diode, and the negative terminal of the third diode. The source of the first MOSFET is connected to the positive terminal of the second diode and one end of the first capacitor. The other end of the first capacitor is connected to the drain of the second MOSFET. The source of the second MOSFET is connected to the negative input terminal. The positive terminal of the third diode is connected to one end of the second inductor and the negative terminal of the fourth diode. The other end of the second inductor is connected to the positive output terminal and the positive terminal of the second capacitor. The other end of the second capacitor C2 is connected to the negative output terminal.