CN207884509U - A kind of AC-DC translation circuits based on DC-DC chips - Google Patents

Abstract

The utility model is related to translation circuit field, AC DC translation circuit of the utility model based on DC DC chips is simple in structure, does not use transformer, output voltage is more more stable than traditional switch power supply, effect higher, electromagnetic interference smaller, and also cost is lower, volume smaller.Wherein, the alternating current of AC power input carries out rectification and is filtered to become high-voltage direct current by current rectifying and wave filtering circuit, then the output end output control signal control drive circuit of DC DC chip circuits, pass through the on or off of the triode of driving circuit driving switch control circuit, to control the break-make of high-voltage direct current, last filtered output DC electric current.In addition, feedback circuit feeds back output voltage, DC DC chip circuits are detected, if output voltage is excessively high, is controlled ON-OFF control circuit in advance and are closed output voltage.

Description

A kind of AC-DC translation circuits based on DC-DC chips

Technical field

The utility model is related to translation circuit field, espespecially a kind of AC-DC translation circuits based on DC-DC chips.

Background technology

In current AC-DC Switching Power Supplies, special chip is generally used, of high cost, volume is big, and is generally isolated Formula, using transformer so that circuit structure is complicated, working efficiency is low and big by electromagnetic interference, is not sufficiently stable so that single fire switch There is flicker problem when closing in power supply.

In addition, generally in the electric current of 80uA to 120uA when single fiery Switching Power Supply static state currently on the market, and when with load, When taking the load of 3.5mA control panels, electric current can will appear the case where LED light flickers at this time in 120uA or more.

Invention content

To solve the above problems, the utility model provide it is a kind of be applied to single fiery Switching Power Supply, it is at low cost, work efficiency is high And the operation is stable, the non-isolated AC-DC translation circuits based on DC-DC chips.

To achieve the above object, the technical solution adopted in the utility model is：A kind of AC-DC changes based on DC-DC chips Change circuit, including AC power input, current rectifying and wave filtering circuit, DC-DC chip circuits, driving circuit, ON-OFF control circuit, feedback Circuit, the AC power input are connect with current rectifying and wave filtering circuit input terminal, the rectification filter circuit output end respectively with open Control circuit input terminal, the connection of DC-DC chip circuit input terminals are closed, the ON-OFF control circuit output end is inputted with feedback circuit End connection, the feedback circuit output connect with DC-DC chip circuit input terminals, the DC-DC chip circuits output end and Driving circuit input terminal connects, and the driving circuit output end is connect with ON-OFF control circuit input terminal, the switch control electricity Road output end is as DC output ends.

Specifically, the DC-DC chip circuits include second resistance R2,3rd resistor R3, the DC-DC chip for sampling U5, third capacitance C3, the 4th capacitance C4, the one end the second resistance R2 are connect with rectification filter circuit output end, and described second The resistance R2 other ends are connect with DC-DC chip U5 input terminals, and also pass through third capacitance C3,3rd resistor R3 ground connection, institute respectively The ends SW for stating DC-DC chips U5 are connect with driving circuit input terminal, the ends SW of the DC-DC chips U5 by the 4th capacitance C4 with Its end BS connects, and the feedback circuit is connect with the ends FB of DC-DC chips U5.

Specifically, the driving circuit includes the 5th resistance R5, the first triode Q1, first resistor R1, the 4th resistance R4, Described 5th one end resistance R5 is connect with DC-DC chip circuit output ends, and the other end is connect with the base stage of the first triode Q1, institute The collector for stating the first triode Q1 is connect with ON-OFF control circuit input terminal respectively by first resistor R1, the 4th resistance R4, Emitter is grounded.

Specifically, the ON-OFF control circuit includes the second triode Q2, inductance L1, the base stage of the second triode Q2 It is connect respectively with driving circuit output end with emitter, the second triode Q2 collectors are connect with the one end inductance L1, described The inductance L1 other ends are as DC output ends.

Specifically, the current input terminal of the inductance L1 is grounded by diode D1, and the current output terminal of the other end passes through 5th capacitance C5 ground connection.

Specifically, the feedback circuit includes the 7th resistance R7 for sampling, the tenth resistance R10, the 7th resistance The one end R7 is connect with ON-OFF control circuit output end, the 7th resistance R7 other ends and DC-DC chip circuit feedback input ends Connection, and pass through the tenth resistance R10 ground connection simultaneously.

Specifically, filter capacitor C1, the filter capacitor C1 are additionally provided between the ON-OFF control circuit and DC output ends One end is connect with ON-OFF control circuit output end, other end ground connection.

The beneficial effects of the utility model are：AC-DC translation circuit structure letter of the utility model based on DC-DC chips It is single, transformer is not used, output voltage is more more stable than traditional switch power supply, effect higher, electromagnetic interference smaller, and cost Lower, volume smaller.Wherein, the alternating current of AC power input carries out rectification by current rectifying and wave filtering circuit and is filtered change For high-voltage direct current, then the output end output control signal control drive circuit of DC-DC chip circuits, passes through driving circuit The on or off of the triode of driving switch control circuit, it is last filtered to control the break-make of high-voltage direct current Export DC electric current.In addition, feedback circuit feeds back output voltage, DC-DC chip circuits are detected, if output voltage It is excessively high, ON-OFF control circuit is controlled in advance closes output voltage.

Description of the drawings

Fig. 1 is the structure diagram of the utility model.

Fig. 2 is the circuit diagram of the utility model.

Drawing reference numeral explanation：1. AC power input；2. current rectifying and wave filtering circuit；3.DC-DC chip circuits, 4. driving electricity Road；5. ON-OFF control circuit；6. feedback circuit；7.DC output ends.

Specific implementation mode

Refering to Figure 1, the utility model is about a kind of AC-DC translation circuits based on DC-DC chips, including AC electricity Source input terminal 1, current rectifying and wave filtering circuit 2, DC-DC chip circuits 3, driving circuit 4, ON-OFF control circuit 5, feedback circuit 6, it is described AC power input 1 is connect with 2 input terminal of current rectifying and wave filtering circuit, and 2 output end of the current rectifying and wave filtering circuit is controlled with switch respectively 5 input terminal of circuit, the connection of 3 input terminal of DC-DC chip circuits, 5 output end of the ON-OFF control circuit and 6 input terminal of feedback circuit Connection, 6 output end of the feedback circuit connect with 3 input terminal of DC-DC chip circuits, 3 output end of DC-DC chip circuits and 4 input terminal of driving circuit connects, and 4 output end of the driving circuit is connect with 5 input terminal of ON-OFF control circuit, the switch control 5 output end of circuit is as DC output ends 7.

Specifically, it please refers to shown in Fig. 2, the DC-DC chip circuits 3 include for the second resistance R2 of sampling, third Resistance R3, DC-DC chip U5, third capacitance C3, the 4th capacitance C4, the one end the second resistance R2 and current rectifying and wave filtering circuit 2 are defeated Outlet connects, and the second resistance R2 other ends connect with DC-DC chip U5 input terminals, and also respectively by third capacitance C3, 3rd resistor R3 ground connection, the ends SW of the DC-DC chips U5 are connect with 4 input terminal of driving circuit, the SW of the DC-DC chips U5 End is connect by the 4th capacitance C4 with its end BS, and the feedback circuit 6 is connect with the ends FB of DC-DC chips U5.

Specifically, the driving circuit 4 includes the 5th resistance R5, the first triode Q1, first resistor R1, the 4th resistance R4, described 5th one end resistance R5 are connect with 3 output end of DC-DC chip circuits, and the base stage of the other end and the first triode Q1 connect Connect, the collector of the first triode Q1 by first resistor R1, the 4th resistance R4 respectively with ON-OFF control circuit 5 the two or three The emitter of pole pipe Q2, base stage connection, the first triode Q1 emitters ground connection.

Specifically, the ON-OFF control circuit 5 includes the second triode Q2, inductance L1, the base of the second triode Q2 Pole and emitter are connect with 4 output end of driving circuit respectively, and the second triode Q2 collectors are connect with the one end inductance L1, institute The inductance L1 other ends are stated as DC output ends 7.

Specifically, the current input terminal of the inductance L1 is grounded by diode D1, and the current output terminal of the other end passes through 5th capacitance C5 ground connection.

Specifically, the feedback circuit 6 includes the 7th resistance R7 for sampling, the tenth resistance R10, the 7th resistance The one end R7 is connect with 5 output end of ON-OFF control circuit, the 7th resistance R7 other ends and 3 feed back input of DC-DC chip circuits The connection of the ends FB is held, and passes through the tenth resistance R10 ground connection simultaneously.

Specifically, filter capacitor C1, the filter capacitor are additionally provided between the ON-OFF control circuit 5 and DC output ends 7 The one end C1 is connect with 5 output end of ON-OFF control circuit, other end ground connection.

Compared with prior art, AC-DC translation circuit of the utility model based on DC-DC chips is simple in structure, does not make With transformer, output voltage is more more stable than traditional switch power supply, effect higher, electromagnetic interference smaller, and cost is lower, volume Smaller.Wherein, the alternating current of AC power input 1 carries out rectification and is filtered to become high pressure by current rectifying and wave filtering circuit 2 DC current, then the output end output control signal control drive circuit 4 of DC-DC chip circuits 3, is driven by driving circuit 4 The on or off of second triode Q2 of dynamic ON-OFF control circuit 5 finally carries out to control the break-make of high-voltage direct current Filtering output DC electric current.In addition, feedback circuit 6 feeds back output voltage, DC-DC chip circuits 3 are detected, if defeated Go out overtension, controls ON-OFF control circuit 5 in advance and close output voltage.This specific embodiment is applied to be designed in single ignition source In, it can be less than 20uA electric currents when static, and with there was only 80uA electric currents when carrying, the flicker of LED light can be inhibited to ask significantly Topic.

Embodiment of above is only that preferred embodiments of the present invention are described, not to the utility model Range be defined, under the premise of not departing from the spirit of the design of the utility model, this field ordinary engineering and technical personnel to this The various modifications and improvement that the technical solution of utility model is made should all fall into the guarantor that claims of the utility model determine It protects in range.

Claims (7)

1. a kind of AC-DC translation circuits based on DC-DC chips, it is characterised in that：Including AC power input, rectifying and wave-filtering electricity Road, DC-DC chip circuits, driving circuit, ON-OFF control circuit, feedback circuit, the AC power input and rectifying and wave-filtering electricity Road input terminal connection, the rectification filter circuit output end are inputted with ON-OFF control circuit input terminal, DC-DC chip circuits respectively End connection, the ON-OFF control circuit output end are connect with feedback circuit input terminal, the feedback circuit output and DC-DC cores Piece circuit input end connects, and the DC-DC chip circuits output end is connect with driving circuit input terminal, the driving circuit output End is connect with ON-OFF control circuit input terminal, and the ON-OFF control circuit output end is as DC output ends.

2. a kind of AC-DC translation circuits based on DC-DC chips according to claim 1, it is characterised in that：The DC- DC chip circuits include the second resistance for sampling（R2）, 3rd resistor（R3）, DC-DC chips（U5）, third capacitance（C3）、 4th capacitance（C4）, the second resistance（R2）One end is connect with rectification filter circuit output end, the second resistance（R2）Separately One end and DC-DC chips（U5）Input terminal connects, and also passes through third capacitance respectively（C3）, 3rd resistor（R3）Ground connection is described DC-DC chips（U5）The ends SW connect with driving circuit input terminal, the DC-DC chips（U5）The ends SW pass through the 4th capacitance （C4）It is connect with its end BS, the feedback circuit and DC-DC chips（U5）The ends FB connection.

3. a kind of AC-DC translation circuits based on DC-DC chips according to claim 1, it is characterised in that：The driving Circuit includes the 5th resistance（R5）, the first triode（Q1）, first resistor（R1）, the 4th resistance（R4）, the 5th resistance （R5）One end is connect with DC-DC chip circuit output ends, the other end and the first triode（Q1）Base stage connection, the described 1st Pole pipe（Q1）Collector pass through first resistor（R1）, the 4th resistance（R4）It connect, sends out with ON-OFF control circuit input terminal respectively Emitter grounding.

4. a kind of AC-DC translation circuits based on DC-DC chips according to claim 1, it is characterised in that：The switch Control circuit includes the second triode（Q2）, inductance（L1）, second triode（Q2）Base stage and emitter respectively with drive Dynamic circuit output end connection, second triode（Q2）Collector and inductance（L1）One end connects, the inductance（L1）It is another End is used as DC output ends.

5. a kind of AC-DC translation circuits based on DC-DC chips according to claim 4, it is characterised in that：The inductance （L1）Current input terminal pass through diode（D1）Ground connection, the current output terminal of the other end pass through the 5th capacitance（C5）Ground connection.

6. a kind of AC-DC translation circuits based on DC-DC chips according to claim 1, it is characterised in that：The feedback Circuit includes the 7th resistance for sampling（R7）, the tenth resistance（R10）, the 7th resistance（R7）One end and switch control electricity Road output end connection, the 7th resistance（R7）The other end is connect with DC-DC chip circuit feedback input ends, and passes through simultaneously Ten resistance（R10）Ground connection.

7. a kind of AC-DC translation circuits based on DC-DC chips according to claim 1, it is characterised in that：The switch It is additionally provided with filter capacitor between control circuit and DC output ends（C1）, the filter capacitor（C1）One end is defeated with ON-OFF control circuit Outlet connects, other end ground connection.