Low-input and wide-range two-path auxiliary power supply circuit

Abstract

The utility model provides a low-input and wide-range two-path auxiliary power supply circuit which comprises a buck converter U1 and a boost voltage stabilizer U2. An input power supply voltage pin VIN and a grounding pin GND of the step-down converter U1 serve as power supply input ports of the auxiliary power supply circuit, and a regulator switch output pin SW of the step-down converter U1 is connected with an inductor L1 in series and then serves as a power supply output port of a first path and a power supply input port of a second path. An input power supply pin IN and a grounding pin GND of the boost voltage stabilizer U2 are used as a power supply input port of a second path; and a power supply switch output pin SW of the boost voltage stabilizer U2 is connected in series with an inductor L2 and then is connected with the power supply input port of the second path. According to the utility model, the problem that the auxiliary power supply part is unstable or does not work during overvoltage and undervoltage can be effectively solved, and the operation stability and reliability of the whole circuit are improved; and two paths of output can better provide auxiliary power supply for adaptive products.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply, in particular to a low-input, wide-range two-way auxiliary power supply circuit. Background Art

[0002] With the advancement of technology, power modules have higher requirements for internal auxiliary power supply circuits, such as small size and lightweight, low input current, wide operating range, and low no-load power consumption. Small size and lightweight can reduce the overall weight of the power supply and adapter products. Combined with low no-load input current, this reduces the power consumption of the product itself and the adapter during operation. Low input current and wide operating range can adapt to complex power supply conditions, ensuring stable auxiliary power supply output when overvoltage, undervoltage, surges, or unstable power supply occurs in the circuit. Two different auxiliary power supply voltages can also be provided simultaneously. Utility Model Content

[0003] The purpose of this utility model is to provide a low-input, wide-range two-way auxiliary power supply circuit, which can effectively solve the problem of instability or non-operation of the auxiliary power supply part during overvoltage or undervoltage, and improve the stability and reliability of the overall circuit operation; the two-way output can better provide auxiliary power supply for the adapted products.

[0004] In order to achieve the above-mentioned objectives, the technical solution adopted by the present invention is: a low-input, wide-range two-way auxiliary power supply circuit, including a buck converter U1 and a boost regulator U2; the input power supply voltage pin VIN and the ground pin GND of the buck converter U1 serve as the power input port of the auxiliary power supply circuit, a capacitor C1 is connected in series between the input power supply voltage pin VIN and the ground pin GND of the buck converter U1, the feedback input pin FB of the buck converter U1 is connected in series with a resistor R2 and then to ground, the power bias pin BST of the MOS driver of the buck converter U1 is connected in series with a capacitor C2 and a diode V1 and then to ground, the regulator switch output pin SW of the buck converter U1 is connected in series with an inductor L1 and serves as the first power output port and the second power input port; the regulator switch output pin SW of the buck converter U1 is connected in series with the output end of the capacitor C2, and the output end of the inductor L1 is connected in series with a resistor R1 and then to a resistor R2;

[0005] The input power pin IN and the ground pin GND of the boost regulator U2 serve as the power input port of the second path. The input power pin IN of the boost regulator U2 is connected in series with resistors R3 and R4 in sequence and then grounded. The regulator switch control pin EN of the boost regulator U2 is connected in series with resistor R4 and then grounded. The feedback input pin FB of the boost regulator U2 is connected in series with resistor R6 and then grounded. The power switch output pin SW of the boost regulator U2 is connected in series with inductor L2 and then connected to the power input port of the second path. The power switch output pin SW of the boost regulator U2 is connected in series with diode V2 and serves as the power output port of the second path. The feedback input pin FB of the boost regulator U2 is connected in series with resistor R5 and then connected to the power input port of the second path. The power output port of the second path is connected in series with capacitor C4 and then grounded.

[0006] Preferably, the buck converter U1 is an asynchronous buck converter with a wide input voltage range from 5.5V to 100V.

[0007] Preferably, the boost regulator U2 is a boost converter that takes an input voltage of 2.3V to 5.5V and outputs an output voltage of 18V.

[0008] The beneficial effects of the utility model are:

[0009] This solution can effectively solve the problem of instability or non-operation of the auxiliary power supply part during over-voltage or under-voltage conditions, and improve the stability and reliability of the overall circuit operation; the two-way output can better provide auxiliary power supply for the adapted products, reduce the no-load input current, reduce the no-load loss, and improve the overall efficiency of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0011] Figure 1 This is the external circuit principle diagram of the utility model. DETAILED DESCRIPTION

[0012] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0013] The structures, proportions, sizes, etc. depicted in the drawings of this specification are only used to match the contents disclosed in this specification so as to facilitate understanding and reading by those familiar with this technology. They are not intended to limit the conditions under which the present invention can be implemented and therefore have no substantive technical significance. Any structural modifications, changes in proportions, or adjustments in sizes shall still fall within the scope of the technical contents disclosed in this utility model without affecting the efficacy and objectives that can be achieved by the present utility model.

[0014] At the same time, it should be noted that: unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with ordinary skills in the technical field to which the utility model belongs. The meaning of "multiple" used in the patent application specification and claims of this utility model is two or more; the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "front end", "rear end", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the utility model. Changes or adjustments to their relative relationships, without substantial changes in the technical content, should also be regarded as the scope of implementation of the utility model.

[0015] The present invention will be described in further detail below in conjunction with the embodiments and with reference to the accompanying drawings.

[0016] The utility model discloses a low-input, wide-range two-way auxiliary power supply circuit. Figure 1 As shown, the embodiment includes a buck converter U1 and a boost regulator U2. The specific model of the buck converter U1 is SCT2A26STER, and the specific model of the boost regulator U2 is RM3716ED6.

[0017] The buck converter U1 is an asynchronous buck converter with a wide input voltage range from 5.5V to 100V. The buck converter U1 includes eight pins, namely a ground pin GND, an input power supply voltage pin VIN, an enable pull-up pin EN, a reset pin RT, an output pin FB of an inverting comparator, a test analog pin TM, a power supply bias pin BST of a MOS driver, and a regulator switch output pin SW.

[0018] The boost regulator U2 is a step-up converter that accepts an input voltage between 2.3V and 5.5V and outputs an 18V output voltage. The boost regulator U2 includes six pins: a NC pin, an input power pin, an EN pin for regulator switching, a FB pin for feedback input, a GND pin, and a SW pin for power switch output.

[0019] The input power supply voltage pin VIN and the ground pin GND of the buck converter U1 serve as the power input ports of the auxiliary power supply circuit. A capacitor C1 is connected in series between the input power supply voltage pin VIN and the ground pin GND of the buck converter U1. The feedback input pin FB of the buck converter U1 is connected in series with a resistor R2 and then to ground. The power bias pin BST of the MOS driver of the buck converter U1 is connected in series with a capacitor C2 and a diode V1 and then to ground. The regulator switch output pin SW of the buck converter U1 is connected in series with an inductor L1 and serves as the first power output port and the second power input port. The regulator switch output pin SW of the buck converter U1 is connected in series with the output end of the capacitor C2, and the output end of the inductor L1 is connected in series with a resistor R1 and then with a resistor R2.

[0020] The input power pin IN and the ground pin GND of the boost regulator U2 serve as the power input port of the second path. The input power pin IN of the boost regulator U2 is connected in series with resistors R3 and R4 in sequence and then grounded. The regulator switch control pin EN of the boost regulator U2 is connected in series with resistor R4 and then grounded. The feedback input pin FB of the boost regulator U2 is connected in series with resistor R6 and then grounded. The power switch output pin SW of the boost regulator U2 is connected in series with inductor L2 and then connected to the power input port of the second path. The power switch output pin SW of the boost regulator U2 is connected in series with diode V2 and serves as the power output port of the second path. The feedback input pin FB of the boost regulator U2 is connected in series with resistor R5 and then connected to the power input port of the second path. The power output port of the second path is connected in series with capacitor C4 and then grounded.

[0021] After the circuit is powered on, the buck converter U1 steps down the output DC auxiliary voltage Vout1, which supplies power to U2, and the boost regulator U2 steps up the output DC auxiliary voltage Vout2.

[0022] It should be noted that the parts not described in detail in the above embodiments are all prior art.

[0023] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment, it is not intended to limit the present invention. Any technician familiar with the present invention can make slight changes or modifications to equivalent embodiments using the technical content disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention should be included in the scope of protection of the present invention.

Claims

1. A low-input, wide-range two-way auxiliary power supply circuit, characterized by: The invention comprises a buck converter U1 and a boost regulator U2; the input power supply voltage pin VIN and the ground pin GND of the buck converter U1 serve as power input ports of the auxiliary power supply circuit; a capacitor C1 is connected in series between the input power supply voltage pin VIN and the ground pin GND of the buck converter U1; a feedback input pin FB of the buck converter U1 is connected in series with a resistor R2 and then to ground; a power bias pin BST of the MOS driver of the buck converter U1 is connected in series with a capacitor C2 and a diode V1 and then to ground; a regulator switch output pin SW of the buck converter U1 is connected in series with an inductor L1 and serves as a first power output port and a second power input port; the regulator switch output pin SW of the buck converter U1 is connected in series with the output end of the capacitor C2; the output end of the inductor L1 is connected in series with a resistor R1 and then to a resistor R2; The input power pin IN and the ground pin GND of the boost regulator U2 serve as the power input port of the second path. The input power pin IN of the boost regulator U2 is connected in series with resistors R3 and R4 in sequence and then grounded. The regulator switch control pin EN of the boost regulator U2 is connected in series with resistor R4 and then grounded. The feedback input pin FB of the boost regulator U2 is connected in series with resistor R6 and then grounded. The power switch output pin SW of the boost regulator U2 is connected in series with inductor L2 and then connected to the power input port of the second path. The power switch output pin SW of the boost regulator U2 is connected in series with diode V2 and serves as the power output port of the second path. The feedback input pin FB of the boost regulator U2 is connected in series with resistor R5 and then connected to the power input port of the second path. The power output port of the second path is connected in series with capacitor C4 and then grounded.

2. The low-input, wide-range two-way auxiliary power supply circuit according to claim 1, characterized in that: The buck converter U1 is an asynchronous buck converter with a wide input voltage range from 5.5V to 100V.

3. The low-input, wide-range two-way auxiliary power supply circuit according to claim 1, characterized in that: The boost regulator U2 is a boost converter that takes in an input voltage of 2.3V to 5.5V and outputs an 18V output voltage.

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