CN207098941U - Self coupling type switching power supply - Google Patents

Abstract

The utility model discloses a kind of self coupling type Switching Power Supply, including switching pulse control chip, change voltage inductance and rectification unit；The input access input voltage of switching pulse control chip, output end are in series with becoming voltage inductance；Become voltage inductance to be connected with rectification unit, the output end output conversion voltage of rectification unit.By the technical solution of the utility model, while the conversion that high efficiency, output stabilization are carried out to voltage is realized, cost is reduced, reduces the volume of self coupling type Switching Power Supply, so as to improve the scope of application of self coupling type Switching Power Supply.

Description

Self-coupling switching power supply

technical field

The utility model relates to the technical field of power transformation devices, in particular to an auto-coupling switching power supply.

Background technique

In the prior art, as shown in Figure 1, the switching power supply needs to use a transformer to realize energy coupling and step-down conversion, and the feedback circuit also needs the transformer to add a separate winding to provide auxiliary power supply. However, the transformer occupies A larger device space is obtained, and the production cost is increased.

Utility model content

Aiming at at least one of the above-mentioned problems, the utility model provides an auto-coupling switching power supply. By replacing the high-frequency transformer with high price and large size with an inductor with low price and small size, the high voltage is realized. While improving the conversion efficiency and stable output, the cost is reduced and the volume of the switching power supply is reduced.

In order to achieve the above purpose, the utility model provides a self-coupling switching power supply, including a switching pulse control chip, a transformer inductor and a rectifier unit; the input terminal of the switching pulse control chip is connected to the input voltage, and the output terminal is connected to the transformer inductor connected in series; the transformer inductor is connected with the rectifier unit, and the output terminal of the rectifier unit outputs the converted voltage.

In the above technical solution, preferably, the above-mentioned self-coupling switching power supply further includes a feedback unit, the input end of the feedback unit is connected to the output end of the rectification unit, and the output end of the feedback unit is connected to the switching pulse control chip and the transformer after being connected in series. inductors in parallel.

In the above technical solution, preferably, the rectification unit includes a capacitor and a diode, and the capacitor and the diode are connected in parallel with the transformer inductor after being connected in series.

In the above technical solution, preferably, the feedback unit includes an optocoupler, a Zener diode and a resistor, and the Zener diode and the resistor are connected in series between the optocoupler and the output terminal of the transformer inductor, and the emitter of the optocoupler output terminal is controlled by the switch pulse chip connected.

In the above technical solution, preferably, the above-mentioned self-coupling switching power supply also includes an auxiliary power rectification unit, the auxiliary power rectification unit includes an auxiliary capacitor and an auxiliary diode, and the auxiliary capacitor and the auxiliary diode are connected in parallel with the transformer inductor after being connected in series. The negative pole is connected to the collector of the output terminal of the optocoupler.

Compared with the prior art, the beneficial effects of the utility model are:

1. By replacing the high-frequency transformer with high price and large size with an inductor with low price and small size, while realizing high-efficiency and stable output conversion of voltage, the cost is reduced and the number of auto-coupling switches is reduced. The size of the power supply increases the scope of application of the self-coupling switching power supply.

2. The feedback unit detects the fluctuation of the conversion voltage and transmits it to the switch pulse control chip, so that the switch pulse control chip adjusts the switch on and off according to the fluctuation of the conversion voltage, thereby controlling the time interval or frequency of charging and discharging of the transformer inductor, thereby improving Accuracy and stability of converted voltage. At the same time, since some feedback units need to provide auxiliary power supply, the output terminal of the feedback unit is connected to the transformer inductor to provide auxiliary power for the feedback unit without affecting the power supply of the main power supply, which further improves the existing technology. It is necessary to add a separate winding to the transformer to provide auxiliary power, which brings problems of high cost and large volume.

3. The rectifier unit includes capacitors and diodes. Using the characteristics of capacitors to block DC and AC, as well as the forward and reverse properties of diodes, the AC power formed by the charge and discharge intervals of the transformer inductor is rectified and converted into DC output.

4. The input end of the optocoupler in the feedback unit is connected to the output end of the rectifier unit through a resistor and a Zener diode. The light emitter in the optocoupler emits light of corresponding intensity according to the detected voltage, and the light receiver in the optocoupler receives it. After the optical signal, a photocurrent is generated to realize the conversion process of "electricity-optical-electricity". The input and output electrical signals are well isolated with light as the medium, and the electrical insulation and anti-interference ability of the feedback circuit is improved, so that the feedback circuit The feedback signal of the unit retains the fluctuation of the conversion voltage, so that the switch pulse control chip can adjust the time interval or frequency of switching on and off according to the feedback fluctuation of the conversion voltage, and improve the accuracy and stability of the conversion voltage.

5. The auxiliary capacitor and the auxiliary diode form a rectification circuit, and are connected to the collector of the output terminal of the optocoupler to provide auxiliary power supply for the circuit of the feedback unit without affecting the power supply of the main power supply. Adding a separate winding to provide auxiliary power brings about higher cost and larger volume.

Description of drawings

Fig. 1 is a schematic circuit connection diagram of an auto-coupling switching power supply disclosed in an embodiment of the prior art;

Fig. 2 is a schematic block diagram of the circuit connection of the self-coupling switching power supply disclosed by an embodiment of the utility model;

Fig. 3 is a schematic diagram of the circuit connection of the self-coupling switching power supply disclosed in an embodiment of the present invention;

Fig. 4 is a schematic diagram of the charging principle of the transformer inductor in the self-coupling switching power supply disclosed in the embodiment shown in Fig. 3;

FIG. 5 is a schematic diagram of the discharge principle of the transformer inductor in the self-coupling switching power supply disclosed in the embodiment shown in FIG. 3 .

In the figure, the corresponding relationship between each component and the reference numerals is:

10. Self-coupling switching power supply, 11. Rectification unit, 12. Feedback unit, 13. Auxiliary power supply rectification unit, U1. Switch pulse control chip, U2. Optocoupler, T1. Transformer, L1. Transformer inductor, C1. Capacitor , D1. Diode, C2. Auxiliary capacitor, D2. Auxiliary diode, D5. Zener diode, R1. Resistor, V1. Input voltage, V2. Conversion voltage.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the utility model more clear, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the utility model. Obviously, the described The embodiments are some embodiments of the present utility model, but not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

Below in conjunction with accompanying drawing, the utility model is described in further detail:

As shown in Figures 2 and 3, a self-coupling switching power supply 10 provided according to the utility model includes a switching pulse control chip U1, a transformer inductor L1 and a rectifier unit 11; the input terminal of the switching pulse control chip U1 is connected to The input voltage V1 is connected in series with the output terminal of the transformer inductor L1; the transformer inductor L1 is connected with the rectifier unit 11, and the output terminal of the rectifier unit 11 outputs the converted voltage V2.

In this embodiment, by replacing the transformer used for energy coupling and step-down conversion in the prior art with a transformer inductor L1, the voltage conversion is realized through the self-coupling charge and discharge of the transformer inductor L1, which reduces the cost , reducing the volume of the self-coupling switching power supply 10 device.

Specifically, the switch pulse control chip U1 is used to convert the input DC power into a pulse current. After the auto-charge and discharge step-down of the transformer inductor L1, the rectifier unit 11 filters and rectifies it into a DC output to realize the conversion of high DC voltage. for DC low voltage.

In the above embodiment, preferably, the above-mentioned self-coupling switching power supply 10 further includes a feedback unit 12, the input end of the feedback unit 12 is connected to the output end of the rectification unit 11, and the output end is connected to the switching pulse control chip U1 and Transformer inductor L1 is connected in parallel.

In this embodiment, the feedback unit 12 detects the fluctuation of the conversion voltage V2, and transmits it to the switch pulse control chip U1, so that the switch pulse control chip U1 adjusts the on-off of the switch according to the fluctuation of the conversion voltage V2, thereby controlling the charging of the transformer inductor L1. The time interval or frequency of the discharge, thereby improving the accuracy and stability of the converted voltage V2. At the same time, since part of the feedback unit 12 needs to provide an auxiliary power supply, the output end of the feedback unit 12 is connected to the transformer inductor L1 to provide the auxiliary power supply for the feedback unit 12 without affecting the power supply of the main power supply, further solving the problem of In the prior art, a separate winding needs to be added to the transformer to provide the auxiliary power supply, which brings problems of high cost and large volume.

In the above embodiment, preferably, the rectification unit 11 includes a capacitor C1 and a diode D1, and the capacitor C1 and the diode D1 are connected in series and then connected in parallel with the transformer inductor L1.

In this embodiment, the rectifier unit 11 includes a capacitor C1 and a diode D1. Using the characteristics of the capacitor C1 to block DC and AC, and the forward and reverse properties of the diode D1, the alternating current formed by charging and discharging the transformer inductor L1 is Perform rectification and convert to DC output.

In the above embodiment, preferably, the feedback unit 12 includes an optocoupler U2, a Zener diode D5 and a resistor R1, the resistor R1 and the Zener diode D5 are connected in series between the optocoupler U2 and the output end of the transformer inductor L1, and the optocoupler The emitter at the output end of U2 is connected with the switching pulse control chip U1.

In this embodiment, the input end of the optocoupler U2 in the feedback unit 12 is connected to the output end of the rectifier unit 11 through the resistor R1 and the Zener diode D5, and the light emitter in the optocoupler U2 emits a light of corresponding intensity according to the detected voltage. Light, the light receiver in the optocoupler U2 generates photocurrent after receiving the light signal, realizing the conversion process of "electricity-optical-electricity", using light as a medium to isolate the input and output electrical signals well, and improving the feedback circuit electrical insulation and anti-interference ability, so that the feedback signal of the feedback unit 12 retains the fluctuation of the conversion voltage V2, so that the switch pulse control chip U1 adjusts the time interval or frequency of the switch on and off according to the fluctuation of the feedback conversion voltage V2, improving The accuracy and stability of the converted voltage V2.

In the above embodiment, preferably, the self-coupling switching power supply 10 further includes an auxiliary power rectification unit 13, and the auxiliary power rectification unit 13 includes an auxiliary capacitor C2 and an auxiliary diode D2, and the auxiliary capacitor C2 and the auxiliary diode D2 are connected in series with the transformer The piezoelectric inductor L1 is connected in parallel, and the cathode of the auxiliary diode D2 is connected to the collector of the output terminal of the optocoupler U2.

In this embodiment, the auxiliary capacitor C2 and the auxiliary diode D2 form a rectifier circuit and are connected to the collector of the output terminal of the optocoupler U2 to provide auxiliary power supply for the circuit of the feedback unit 12 without affecting the power supply of the main power supply, improving the In the prior art, a separate winding needs to be added to the transformer to provide the auxiliary power supply, which brings problems of high cost and large volume.

Wherein, the feedback unit 12 in the above-mentioned self-coupling switching power supply 10 can also use other circuits that do not require auxiliary power, and for the feedback unit 12 that does not require auxiliary power, the auxiliary power sorting unit can also be eliminated.

As shown in FIG. 4 , during the charging process of the transformer inductor L1 in the above embodiment, when the output state of the switching pulse control chip U1 is turned on, the input voltage V1 charges the inductor and the capacitor C1 . The direction indicated by the dotted arrow in the figure is the direction of the charging current.

As shown in Figure 5, during the charging process of the transformer inductor L1 in the above embodiment, when the output state of the switch pulse control chip U1 is off, the electric energy stored in the inductor is discharged through two parallel circuits, and one is filtered by the capacitor C1 The converted main power supply voltage V2 is the auxiliary power supply rectified and filtered by the auxiliary diode D2 and the auxiliary capacitor C2 , which supplies power to the optocoupler U2 in the feedback unit 12 . Through the charging and discharging process described above, the input voltage V1 is converted into a converted voltage V2. The direction indicated by the dotted arrow in the figure is the direction of the discharge current.

It is worth mentioning that the above-mentioned self-coupling switching power supply 10 is suitable for applications where the input voltage and the conversion voltage are not isolated.

The above is the embodiment of the utility model. Considering the technical problems of high cost and large volume of the transformer in the switching power supply in the prior art, the utility model proposes a self-coupling switching power supply, which is high in price and large in size. The high-frequency transformer is replaced by an inductance with low price and small size. The pulse current is used to convert the voltage through the charging and discharging process of the transformer inductance. While realizing the high-efficiency and stable output conversion of the voltage, the cost is reduced and the The volume of the self-coupling switching power supply is reduced, thereby improving the application range of the self-coupling switching power supply.

The above are only preferred embodiments of the utility model, and are not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (6)

1. A self-coupling switching power supply, characterized in that, comprising: a switching pulse control chip, a transformer inductor and a rectifying unit; The input terminal of the switching pulse control chip is connected to the input voltage, and the output terminal is connected in series with the transformer inductor; The transformer inductor is connected to the rectification unit, and the output end of the rectification unit outputs a converted voltage. 2. The self-coupling switching power supply according to claim 1, further comprising a feedback unit, the input end of the feedback unit is connected to the output end of the rectification unit, and the output ends of the feedback unit are respectively It is connected with the switch pulse control chip and the transformer inductor. 3 . The self-coupling switching power supply according to claim 1 , wherein the rectification unit includes a capacitor and a diode, and the capacitor and the diode are connected in parallel with the transformer inductor after being connected in series. 4 . 4 . The self-coupling switching power supply according to claim 2 , wherein the rectification unit includes a capacitor and a diode, and the capacitor and the diode are connected in parallel with the transformer inductor after being connected in series. 5. The self-coupling switching power supply according to claim 2 or 4, wherein the feedback unit includes an optocoupler, a Zener diode and a resistor, and the Zener diode and the resistor are connected in series to the optocoupler Between the output end of the transformer inductor and the output end of the optocoupler, the emitter of the output end of the optocoupler is connected to the switching pulse control chip. 6. The self-coupling switching power supply according to claim 5, further comprising an auxiliary power rectification unit, the auxiliary power rectification unit comprising an auxiliary capacitor and an auxiliary diode, and the auxiliary capacitor and the auxiliary diode are connected in series Afterwards, it is connected in parallel with the transformer inductor, and the cathode of the auxiliary diode is connected with the collector of the output terminal of the optocoupler.