LC series-parallel composite boost circuit

Abstract

The utility model discloses an LC series-parallel composite booster circuit, which comprises a direct-current power supply, a first parallel resonance circuit, a second series resonance circuit, a switch control circuit, a driving end, a voltage output end and a detection end, according to the utility model, the LC parallel resonance and LC series resonance of the inductor and the capacitor are combined for use, the coupled voltage is subjected to secondary resonance composite boosting, the output voltage is improved by geometric multiples, and the standby current of the product can be effectively reduced because the LC parallel resonance can generate enough inductive reactance, so that the boosting efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of boost circuits, in particular to an LC series-parallel composite boost circuit. Background Art

[0002] With the rapid development of electronic technology, a large number of electronic products have higher voltage requirements for the working conditions of the products. Also subject to the limitations of the general electromagnetic induction boosting technology, the transformer has a primary coil and a secondary coil, and the two are inseparable. Or there are problems such as low voltage and efficiency of single-channel inductance boosting technology. As a result, the boosting part of the product is large in size and will also cause a lot of heat. In addition, the existing boosting technology is prone to generate harmonics and other resonant waveforms that are very likely to cause circuit interference, and it is difficult to eliminate. This affects the quality and service life of the product. Usually in circuit design, when it is necessary to achieve extremely high voltage and the volume is limited, the wire diameter of the transformer is easily limited, making the heating phenomenon of the coil internal resistance particularly obvious and difficult to dissipate heat. The ultra-high requirements of traditional transformers for the insulation performance of the primary and secondary coils will also lead to high overall costs. In the traditional high-power transformer boosting coil, silicon steel sheets are usually added to increase the magnetic flux, and the resulting eddy current effect will inevitably reduce the boosting efficiency. Utility Model Content

[0003] In view of this, the main purpose of the utility model is to provide an LC series-parallel composite boost circuit.

[0004] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0005] The embodiment of the utility model provides an LC series-parallel composite boost circuit, including a DC power supply, a first parallel resonant circuit, a second series resonant circuit, a switch control circuit, a driving end, a voltage output end, and a detection end;

[0006] The DC power supply is connected to the first end of the first parallel resonant circuit and is used to provide DC power;

[0007] The first end of the second series resonant circuit is respectively connected to the second end of the first parallel resonant circuit, the first end of the switch control circuit and the detection end, and the second end of the second series resonant circuit is connected to the voltage output end;

[0008] The control end of the switch control circuit is connected to the driving end.

[0009] In the above solution, the first parallel resonant circuit includes a first capacitor and a first inductor, and the first end of the first capacitor is connected to the DC power supply and the first end of the first inductor respectively.

[0010] In the above solution, the switch control circuit includes an N-channel MOS transistor, and the drain of the N-channel MOS transistor is respectively connected to the second end of the first capacitor, the second end of the first inductor and the detection end.

[0011] In the above scheme, the second series resonant circuit includes a second capacitor and a second inductor, the first end of the second inductor is connected to the drain of the N-channel MOS tube, the second end of the second inductor is respectively connected to the first end of the second capacitor and the voltage output end, and the second end of the second capacitor is connected to the source of the N-channel MOS tube and then grounded.

[0012] In the above solution, the gate of the N-channel MOS tube is connected to the driving end.

[0013] In the above solution, the driving end can input a rectangular wave, a sawtooth wave, a sine wave or a PWM modulated wave.

[0014] Compared with the prior art, the utility model has the following beneficial effects:

[0015] The utility model utilizes the method of combining the LC parallel resonance of the inductor and the capacitor with the LC series resonance, and performs secondary resonance composite boosting on the coupled voltage, so that the output voltage is increased geometrically, and because the LC parallel resonance can generate sufficient inductive reactance, the standby current of the product can be effectively reduced, thereby improving the boosting efficiency. This circuit also utilizes the LC resonance method, which can amplify the amplitude of the operating frequency signal while suppressing all frequency bands other than the operating frequency, so that parasitic noise can be perfectly eliminated to achieve a complete and clean boosting frequency, so that the boosted voltage has no surge and noise, so as to ensure that the product can extend its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to disclose a further understanding of the present invention and constitute a part of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0017] Figure 1 It is a structural schematic diagram of an LC series-parallel composite boost circuit described in an embodiment of the utility model. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0019] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of the present utility model, it should be understood that the terms "first", "second", "third", etc. are only for the convenience of distinguishing and describing the same components, rather than indicating or implying the number of the referred elements, and cannot be understood as a limitation of this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0020] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, article or device. In the absence of more restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, article or device including the element.

[0021] The first embodiment of the utility model provides an LC series-parallel composite boost circuit, such as Figure 1 As shown, it includes a DC power supply VDD, a first parallel resonant circuit, a second series resonant circuit, a switch control circuit, a driving terminal IN, a voltage output terminal OUT, and a detection terminal TEST;

[0022] The DC power supply VDD is connected to the first end of the first parallel resonant circuit to provide DC power;

[0023] The first end of the second series resonant circuit is respectively connected to the second end of the first parallel resonant circuit and the first end of the switch control circuit, the second end of the switch control circuit and the detection end TEST, and the second end of the second series resonant circuit is connected to the voltage output end OUT;

[0024] The control end of the switch control circuit is connected to the driving end IN.

[0025] In the above solution, the first parallel resonant circuit includes a first capacitor C1 and a first inductor L1 , and a first end of the first capacitor C1 is connected to a DC power source VDD and a first end of the first inductor L1 , respectively.

[0026] In the above solution, the switch control circuit includes an N-channel MOS transistor M1, and the drain of the N-channel MOS transistor M1 is respectively connected to the second end of the first capacitor C1, the second end of the first inductor L1 and the detection end TEST.

[0027] In the above scheme, the second series resonant circuit includes a second capacitor C2 and a second inductor L2, a first end of the second inductor L2 is connected to the drain of the N-channel MOS transistor M1, a second end of the second inductor L2 is respectively connected to the first end of the second capacitor C2 and the voltage output end OUT, and a second end of the second capacitor C2 is connected to the source of the N-channel MOS transistor M1 and then grounded.

[0028] In the above solution, the gate of the N-channel MOS transistor M1 is connected to the driving terminal IN.

[0029] In the above solution, the driving end IN can input a rectangular wave, a sawtooth wave, a sine wave or a PWM modulated wave.

[0030] Embodiment 2:

[0031] A voltage boosting method of the LC series-parallel composite boosting circuit as described above comprises the following steps:

[0032] S1: First, the parallel resonance of the first capacitor C1 and the first inductor L1 is used to generate an inductive reactance in coordination with the frequency of the input of the driving terminal IN to reduce the standby current of the circuit, so that an AC voltage higher than the DC power supply VDD is generated at the detection terminal TEST;

[0033] S2: using the high voltage AC generated at the detection terminal TEST to drive the LC series resonant circuit composed of the second inductor L2 and the second capacitor C2, so that a high voltage AC level higher than the detection terminal TEST is obtained at the voltage output terminal OUT;

[0034] S3: When the input frequency of the driving end IN is fixed, the ratio of the first capacitor C1 to the first inductor L1 is adjusted to adjust the voltage value at the detection end TEST, and the ratio of the first inductor L1 to the second inductor L2 is adjusted at the same time, so as to adjust the output voltage of the voltage output end OUT. When the values ​​of the first capacitor, the first inductor, the second capacitor, and the second inductor remain unchanged, the output voltage of the output end can also be adjusted by adjusting the input frequency of the driving end.

[0035] The working principle of the utility model is as follows:

[0036] like Figure 1As shown, the circuit of the utility model is divided into two independent working parts, the first part is a first parallel resonant circuit formed by a first capacitor C1 and a first inductor L1; the second part is a second series resonant circuit formed by a second capacitor C2 and a second inductor L2, the switch state of the circuit is controlled by an N-channel MOS tube M1, the circuit is provided with direct current by a direct current power supply VDD, and the driving end IN provides an operating frequency, and the operating frequency can be driven by various frequencies such as rectangular wave, sawtooth wave, sine wave, PWM modulation waveform, etc. to drive the entire circuit to work, and the driving end IN provides different driving waveforms to arbitrarily adjust the output voltage of the voltage output end OUT.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention.

Claims

1. An LC series-parallel composite boost circuit, characterized in that: It includes a DC power supply, a first parallel resonant circuit, a second series resonant circuit, a switch control circuit, a driving end, a voltage output end, and a detection end; The DC power supply is connected to the first end of the first parallel resonant circuit and is used to provide DC power; The first end of the second series resonant circuit is respectively connected to the second end of the first parallel resonant circuit and the first end of the switch control circuit, the second end of the switch control circuit and the detection end, and the second end of the second series resonant circuit is connected to the voltage output end; The control end of the switch control circuit is connected to the driving end.

2. The LC series-parallel composite boost circuit according to claim 1, characterized in that: The first parallel resonant circuit includes a first capacitor and a first inductor, and a first end of the first capacitor is connected to a DC power supply and a first end of the first inductor respectively.

3. The LC series-parallel composite boost circuit according to claim 2, characterized in that: The switch control circuit comprises an N-channel MOS transistor, the drain of which is respectively connected to the second end of the first capacitor, the second end of the first inductor and the detection end.

4. The LC series-parallel composite boost circuit according to claim 3, characterized in that: The second series resonant circuit includes a second capacitor and a second inductor, wherein a first end of the second inductor is connected to the drain of the N-channel MOS tube, a second end of the second inductor is respectively connected to the first end and the voltage output end of the second capacitor, and a second end of the second capacitor is connected to the source of the N-channel MOS tube and then grounded.

5. The LC series-parallel composite boost circuit according to claim 4, characterized in that: The gate of the N-channel MOS tube is connected to the driving end.

6. The LC series-parallel composite boost circuit according to claim 5, characterized in that: The driving end can input a rectangular wave, a sawtooth wave, a sine wave or a PWM modulation wave.

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