CN203788151U - Fly-back switching power supply with adjustable maximal output current - Google Patents
Fly-back switching power supply with adjustable maximal output current Download PDFInfo
- Publication number
- CN203788151U CN203788151U CN201420063419.7U CN201420063419U CN203788151U CN 203788151 U CN203788151 U CN 203788151U CN 201420063419 U CN201420063419 U CN 201420063419U CN 203788151 U CN203788151 U CN 203788151U
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- Prior art keywords
- power supply
- switching power
- circuit
- resistance
- operational amplifier
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Abstract
The utility model relates to a fly-back switching power supply with adjustable maximal output current, which comprises a switching power supply input end, a switching power supply output end, a switching power supply main circuit, a voltage sampling circuit, an integrated control circuit, and a current sampling circuit, wherein an integrated operational amplifier circuit is connected between the current sampling circuit and the integrated control circuit. According to the fly-back switching power supply with adjustable maximal output current, the current sampling circuit amplifies sampling signals via the integrated operational amplifier circuit and then sends the signals to the current sampling end of the integrated control circuit; as the amplification times of the integrated operational amplifier circuit can be adjustable in a large range, allowable maximal output current adjustment can be well carried out on the switching power supply, the output current can be adjusted to the upper limit when the output voltage of the switching power supply is stable, and generality of single end flyback switching power supply products can be improved to a certain degree.
Description
Technical field
The utility model relates to a kind of inverse-excitation type switch power-supply, particularly the adjustable inverse-excitation type switch power-supply of a kind of maximum output current.
Background technology
Single-end flyback switching power supply, because it is simple in structure, needs the element of use few, and cost is low, and volume is little, can realize easily isolation and be easy to realize the many merits such as multichannel output, under the occasion below 200 watts, is widely used, and market is huge; Single-ended flyback power supply constant voltage output at present, the sampling of electric current obtains from the resistance of connecting with power switch pipe, because current sampling resistor resistance is fixed and can not be too little, generally be 1 ohm of left and right, less and the deficiency that can not set of this maximum output current that has just caused power supply to allow, has reduced the versatility of single-end flyback switching power supply product to a certain extent.
Utility model content
The utility model object is the inverse-excitation type switch power-supply that provides a kind of maximum output current adjustable in order to overcome the deficiencies in the prior art.
For achieving the above object, the technical solution adopted in the utility model is: the inverse-excitation type switch power-supply that a kind of maximum output current is adjustable, comprises Switching Power Supply input, Switching Power Supply output, Switching Power Supply main circuit, voltage sample circuit, integral control circuit and current sampling circuit; Described Switching Power Supply input and Switching Power Supply output are arranged on Switching Power Supply main circuit; Described voltage sample circuit and current sampling circuit are electrically connected to integral control circuit respectively, are provided with current sense resistor in current sampling circuit; Described integral control circuit is electrically connected to Switching Power Supply main circuit; Between described current sampling circuit and integral control circuit, be connected with integrated operational amplifier circuit.
Preferably, in described current sampling circuit, current sense resistor is selected the resistance of resistance size between 0.2 milliohm to 6 milliohm.
Preferably, by integrated operational amplifier, the first integrated transporting discharging resistance, the second integrated transporting discharging resistance, integrated transporting discharging, input resistance and integrated transporting discharging regulating resistance form described integrated operational amplifier circuit in the same way; Described the first integrated transporting discharging resistance one end is connected on the reverse input end of integrated operational amplifier, other end ground connection; After described the second integrated transporting discharging resistance and the series connection of integrated transporting discharging regulating resistance, be connected across on the reverse input end and output of integrated operational amplifier; Described integrated transporting discharging in the same way input resistance is connected to the input in the same way of integrated operational amplifier.
Preferably, one end ground connection of described current sense resistor, the other end by integrated transporting discharging in the same way input resistance be connected to the input in the same way of integrated operational amplifier.
Due to the utilization of technique scheme, the utility model compared with prior art has following advantages:
The adjustable inverse-excitation type switch power-supply of maximum output current of the utility model scheme, the resistance of current sense resistor is milliohm level, and after sampled signal is amplified by integrated operational amplifier circuit, delivers to the current sampling end of integral control circuit again; Because the multiplication factor of integrated operational amplifier circuit is adjustable within a large range, therefore, can realize preferably the adjustability of the maximum output current that Switching Power Supply is allowed, during the output voltage stabilization of Switching Power Supply, output current is adjustable to the upper limit, simultaneously integrated manipulator also can normal response, has improved to a certain extent the versatility of single-end flyback switching power supply product.
Accompanying drawing explanation
Below in conjunction with accompanying drawing, technical solutions of the utility model are described further:
Accompanying drawing 1 is the block diagram of the adjustable inverse-excitation type switch power-supply of a kind of maximum output current described in the utility model;
Accompanying drawing 2 is the circuit diagram of the adjustable inverse-excitation type switch power-supply of a kind of maximum output current described in the utility model.
Embodiment
Below in conjunction with drawings and the specific embodiments, the utility model is described in further detail.
As shown in Figure 1-2, the adjustable inverse-excitation type switch power-supply of a kind of maximum output current described in the utility model, comprises Switching Power Supply input, Switching Power Supply output, Switching Power Supply main circuit, voltage sample circuit, integral control circuit and current sampling circuit; Described Switching Power Supply input IN+ and IN-and Switching Power Supply output OUT+ and OUT-are all arranged on Switching Power Supply main circuit, and Switching Power Supply main circuit comprises high frequency transformer T1, power switch pipe Q1, diode D1 and capacitor C 2; Described voltage sample circuit and current sampling circuit are electrically connected to integral control circuit respectively; Described voltage sample circuit comprises the first voltage sampling resistor R1, second voltage sample resistance R6 and voltage sampling regulating resistance RV; Described current sampling circuit comprises current sense resistor RS, and the resistance of current sense resistor RS is 2 milliohms, the primary edge series connection of current sense resistor RS and power switch pipe Q1 and high frequency transformer T1; Described integral control circuit is electrically connected to Switching Power Supply main circuit, and integral control circuit adopts the integrated manipulator that model is UC3843, or has the integrated manipulator of other model of similar functions; Between described current sampling circuit and integral control circuit, be connected with integrated operational amplifier circuit; By integrated operational amplifier, the first integrated transporting discharging resistance R 8, the second integrated transporting discharging resistance R 9, integrated transporting discharging, input resistance R7 and integrated transporting discharging regulating resistance RA form described integrated operational amplifier circuit in the same way; Described the first integrated transporting discharging resistance R 8 one ends are connected on the reverse input end of integrated operational amplifier, other end ground connection; After described the second integrated transporting discharging resistance R 9 and integrated transporting discharging regulating resistance RA series connection, be connected across on the reverse input end and output of integrated operational amplifier; One end ground connection of described current sense resistor RS, the other end by integrated transporting discharging in the same way input resistance R7 be connected to the input in the same way of integrated operational amplifier, wherein integrated operational amplifier employing model is LM358, or has the integrated operational amplifier of other model of similar functions; In other condition all under identical condition, in Fig. 2, single-ended flyback source current sample resistance RS is less, and power switch pipe Q1 ON time is just longer, in the power bracket allowing in main circuit design, during output voltage stabilization, the maximum output current allowing is just larger; Because current sampling resistor RS resistance is milliohm level, and integrated transporting discharging regulating resistance RA adopts be can fine tuning in a big way in resistance potentiometer, the multiplication factor of integrated operational amplifier circuit is in very large range adjustable, the maximum output current that single-end flyback switching power supply is allowed is adjustable, and electric power output voltage is stablized its output current can be adjusted to its upper limit, for example, when single-end flyback switching power supply output voltage is designed to 36V, output current can reach the maximum current 3A of permission.
Due to the utilization of technique scheme, the utility model compared with prior art has following advantages:
The adjustable inverse-excitation type switch power-supply of maximum output current of the utility model scheme, the resistance of current sense resistor is milliohm level, and after sampled signal is amplified by integrated operational amplifier circuit, delivers to the current sampling end of integral control circuit again; Because the multiplication factor of integrated operational amplifier circuit is adjustable within a large range, therefore, can realize preferably the adjustability of the maximum output current that Switching Power Supply is allowed, during the output voltage stabilization of Switching Power Supply, output current is adjustable to the upper limit, simultaneously integrated manipulator also can normal response, has improved to a certain extent the versatility of single-end flyback switching power supply product.
Below be only concrete exemplary applications of the present utility model, protection range of the present utility model is not constituted any limitation.All employing equivalents or equivalence are replaced and the technical scheme of formation, within all dropping on the utility model rights protection scope.
Claims (4)
1. the adjustable inverse-excitation type switch power-supply of maximum output current, comprises Switching Power Supply input, Switching Power Supply output, Switching Power Supply main circuit, voltage sample circuit, integral control circuit and current sampling circuit; Described Switching Power Supply input and Switching Power Supply output are arranged on Switching Power Supply main circuit; Described voltage sample circuit and current sampling circuit are electrically connected to integral control circuit respectively, are provided with current sense resistor in current sampling circuit; Described integral control circuit is electrically connected to Switching Power Supply main circuit; It is characterized in that: between described current sampling circuit and integral control circuit, be connected with integrated operational amplifier circuit.
2. the adjustable inverse-excitation type switch power-supply of maximum output current according to claim 1, is characterized in that: in described current sampling circuit, current sense resistor is selected the resistance of resistance size between 0.2 milliohm to 6 milliohm.
3. the adjustable inverse-excitation type switch power-supply of maximum output current according to claim 1, is characterized in that: by integrated operational amplifier, the first integrated transporting discharging resistance, the second integrated transporting discharging resistance, integrated transporting discharging, input resistance and integrated transporting discharging regulating resistance form described integrated operational amplifier circuit in the same way; Described the first integrated transporting discharging resistance one end is connected on the reverse input end of integrated operational amplifier, other end ground connection; After described the second integrated transporting discharging resistance and the series connection of integrated transporting discharging regulating resistance, be connected across on the reverse input end and output of integrated operational amplifier; Described integrated transporting discharging in the same way input resistance is connected to the input in the same way of integrated operational amplifier.
4. the adjustable inverse-excitation type switch power-supply of maximum output current according to claim 3, is characterized in that: one end ground connection of described current sense resistor, the other end by integrated transporting discharging in the same way input resistance be connected to the input in the same way of integrated operational amplifier.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420063419.7U CN203788151U (en) | 2014-02-13 | 2014-02-13 | Fly-back switching power supply with adjustable maximal output current |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420063419.7U CN203788151U (en) | 2014-02-13 | 2014-02-13 | Fly-back switching power supply with adjustable maximal output current |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203788151U true CN203788151U (en) | 2014-08-20 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420063419.7U Expired - Fee Related CN203788151U (en) | 2014-02-13 | 2014-02-13 | Fly-back switching power supply with adjustable maximal output current |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203788151U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103856060A (en) * | 2014-02-13 | 2014-06-11 | 苏州市职业大学 | Flyback switching power supply with adjustable maximum output current |
| CN110752753A (en) * | 2019-11-04 | 2020-02-04 | 苏州大学 | Inverter booster circuit and booster |
| CN111509979A (en) * | 2019-01-31 | 2020-08-07 | 宏碁股份有限公司 | Voltage converter |
-
2014
- 2014-02-13 CN CN201420063419.7U patent/CN203788151U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103856060A (en) * | 2014-02-13 | 2014-06-11 | 苏州市职业大学 | Flyback switching power supply with adjustable maximum output current |
| CN111509979A (en) * | 2019-01-31 | 2020-08-07 | 宏碁股份有限公司 | Voltage converter |
| CN111509979B (en) * | 2019-01-31 | 2021-07-30 | 宏碁股份有限公司 | Voltage converter |
| CN110752753A (en) * | 2019-11-04 | 2020-02-04 | 苏州大学 | Inverter booster circuit and booster |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140820 Termination date: 20150213 |
|
| EXPY | Termination of patent right or utility model |