CN219761785U - Switching power supply and driver - Google Patents

Abstract

The utility model discloses a switching power supply and a driver, and relates to the technical field of electromechanics. The switching power supply comprises a circuit board and a switching power supply module, wherein the switching power supply module comprises a primary side unit and a secondary side unit; the primary side unit comprises a control chip, a first switching device and a primary side coil, wherein the first switching device is connected with the primary side coil in series so as to control the on-off of the input voltage of the primary side coil through the on-off of the first switching device; the control chip is used for outputting a driving signal to a controlled end of the first switching device so as to control the on-off of the first switching device; the first switching device is fixed on the circuit board by adopting a surface mounting technology. The first switching device is fixed on the circuit board by adopting a surface mounting technology, so that the distance from the first switching device to the circuit board is closer, the first switching device can more conveniently dissipate heat by utilizing the circuit board, and the heat dissipation efficiency of the first switching device and the switching power supply is improved.

Description

Switching power supply and driver

Technical Field

The utility model relates to the technical field of electromechanics, in particular to a switching power supply and a driver.

Background

With the intelligent and digital transformation of manufacturing industry, the requirements on small volume and high power density of the driver are increasing. Wherein the driver is typically provided with a switching power supply, such as a flyback switching power supply or a forward switching power supply; the switching power supply includes a primary unit and a secondary unit, and a coil of the primary unit (primary coil) and a coil of the secondary unit (secondary coil) are generally formed using a coil of a transformer. Typically, the primary side unit of a flyback switching power supply does not provide a power output to a load when energized; and only after the excitation voltage of the primary cell is turned off is the power output provided to the load. The excitation and output of the forward switching power supply are opposite to those of the flyback switching power supply.

As the requirement for small size of the driver is increasing, the heat dissipation efficiency of the switching power supply needs to be further improved.

Disclosure of Invention

The utility model mainly aims to provide a switching power supply, which aims to improve heat dissipation efficiency.

In order to achieve the above object, the present utility model provides a switching power supply applied to a driver; the switching power supply comprises a circuit board and a switching power supply module, wherein the switching power supply module comprises a primary side unit and a secondary side unit; the primary unit comprises a control chip, a first switching device and a primary coil, wherein the first switching device is connected in series with the primary coil so as to control the on-off of the input voltage of the primary coil through the on-off of the first switching device; the control chip is used for outputting a driving signal to a controlled end of the first switching device so as to control the on-off of the first switching device; the first switching device is fixed on the circuit board by adopting a surface mounting technology.

Optionally, the switching power supply further includes a second switching device, where the second switching device is used to control on-off of a line where the primary coil is located, and the second switching device is fixed on the circuit board by using a patch technology.

Optionally, the second switching device is connected in series with the first switching device, and an output end of the control chip is electrically connected with the controlled ends of the first switching device and the second switching device respectively.

Optionally, the circuit board includes a metal layer, a pin of the first switching device is fixedly connected with the metal layer, and a pin of the second switching device is fixedly connected with the metal layer.

Optionally, the metal layer is made of copper foil.

Optionally, the switching power supply further includes a heat sink, and a side of the first switching device facing away from the circuit board abuts against the heat sink.

Optionally, in the case that the switching power supply further includes the second switching device, a side of the second switching device facing away from the circuit board abuts against the heat sink.

Optionally, the switching power supply further comprises a first resistor and a chip power supply circuit, wherein the first resistor is connected with the primary coil in parallel, and the first resistor and the chip power supply circuit are both connected to a power supply pin of the control chip; the chip power supply circuit comprises a power supply coil, wherein the power supply coil is arranged opposite to the secondary side unit, and the power supply coil is used for supplying power to a control pin of the control chip through the formation of reverse electromotive force by the secondary side unit; the chip power supply circuit further comprises a second resistor, a unidirectional conduction element, a power supply coil and a capacitor, wherein the second resistor, the negative electrode of the unidirectional conduction element, the positive electrode of the unidirectional conduction element, the power supply coil and the capacitor are connected end to end in sequence, and a common contact point between the second resistor and the capacitor is connected with a power supply pin of the control chip.

Optionally, the control chip comprises a PWM signal generating circuit, and an output end of the PWM signal generating circuit is connected with a controlled end of the first switching device and/or the second switching device.

The utility model also provides a driver, and the driver is provided with the switching power supply.

According to the technical scheme, the switching power supply comprises a circuit board and a switching power supply module, wherein the switching power supply module comprises a primary side unit and a secondary side unit; the primary unit comprises a control chip, a first switching device and a primary coil, wherein the first switching device is connected with the primary coil in series so as to control the on-off of the input voltage of the primary coil through the on-off of the first switching device; the control chip is used for outputting a driving signal to a controlled end of the first switching device so as to control the on-off of the first switching device; the first switching device is fixed on the circuit board by adopting a surface mounting technology, so that the distance from the first switching device to the circuit board is closer, the first switching device can more conveniently dissipate heat by utilizing the circuit board, and the heat dissipation efficiency of the first switching device and the switching power supply is improved.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic circuit diagram of an embodiment of a switching power supply of the present utility model.

Fig. 2 is a schematic diagram of a partial structure of an embodiment of a switching power supply according to the present utility model.

Fig. 3 is a schematic diagram of a partial structure of another embodiment of the switching power supply of the present utility model.

Fig. 4 is a schematic cross-sectional view of another embodiment of the switching power supply of the present utility model.

Fig. 5 is a schematic circuit diagram of a switching power supply according to another embodiment of the utility model.

Reference numerals illustrate:

reference numerals	Name of the name	Reference numerals	Name of the name
				100	Circuit board	200	Switch power supply module
201	Primary side unit	202	Secondary side unit
				203	Chip power supply circuit	300	Radiator

The achievement of the objects, functional features and advantages of the present utility model will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that, if a directional indication (such as up, down, left, right, front, and rear … …) is involved in the embodiment of the present utility model, the directional indication is merely used to explain the relative positional relationship, movement condition, etc. between the components in a specific posture, and if the specific posture is changed, the directional indication is correspondingly changed.

In addition, if there is a description of "first", "second", etc. in the embodiments of the present utility model, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, if "and/or" and/or "are used throughout, the meaning includes three parallel schemes, for example," a and/or B "including a scheme, or B scheme, or a scheme where a and B are satisfied simultaneously. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.

In the course of research to improve the heat dissipation efficiency of switching power supplies, the applicant found that: in the early technical stage of the switching power supply, the withstand voltage of the MOS tube (Metal Oxide Semiconductor, metal oxide semiconductor field effect end) in the form of the patch at the time is lower than that of the MOS tube in the form of the plug-in material; however, the switching power supply has certain requirements on the withstand voltage of the MOS tube due to the existence of the reflected voltage. Therefore, the skilled person usually uses MOS transistors in the form of plug-ins in switching power supplies with an inertial thinking. Along with the improvement of the small-size requirement of the driver, the height of the MOS tube in the form of the plug-in material is relatively high, so that the radiator with higher efficiency is inconvenient to set, and the heat dissipation efficiency of the switching power supply in the driver under the miniaturization trend is lower.

Thus, the utility model proposes a switching power supply, which may include a forward switching power supply and a flyback switching power supply; the switching power supply is applicable to drives, such as servo drives, stepper drives, etc., although it will be appreciated that it is also applicable to other possible industrial devices, such as: the frequency converter and the like may be specifically determined according to practical situations, and the embodiment of the present specification is not limited thereto.

Referring to fig. 1 and 2, in an embodiment of the present utility model, the switching power supply may include a circuit board 100 and a switching power supply module 200, and the circuit board 100 may be configured as a PCB circuit board. The switching power supply module 200 comprises a primary side unit 201 and a secondary side unit 202, wherein the primary side unit 201 comprises a control chip U0, a first switching device Q1 and a primary side coil Np, and the first switching device Q1 is connected in series with the primary side coil Np so as to control the on-off of the input voltage of the primary side coil Np through the on-off of the first switching device Q1; the control chip U0 is configured to output a driving signal to the controlled end of the first switching device Q1, so as to control on/off of the first switching device Q1.

In this embodiment, the first switching device Q1 may include: the devices such as the MOS transistor and the IGBT may be specifically determined according to actual situations, which is not limited in the embodiment of the present specification.

In one embodiment, taking the first switching device Q1 as an example of a MOS transistor, a signal output end (for outputting the driving signal) on the control chip U0 may be connected to a controlled end (gate) of the first switching device Q1, and a source of the MOS transistor is connected to the primary winding Np and a drain thereof is grounded or connected to a negative terminal. Since the first switching device Q1 generates a relatively high amount of heat, referring to fig. 2, the first switching device Q1 may be fixed on the circuit board 100 using a chip mounting process, for example: the first switching device Q1 uses SMT (Surface Mounted Technology) material. It will be understood, of course, that the first switching device Q1 may be attached to the circuit board 100 in other possible manners, and specifically may be determined according to practical situations, which is not limited in this embodiment of the present disclosure.

In this embodiment, the first switching device Q1 can be conveniently attached to the top layer (top layer) or the bottom layer (bottom layer) of the circuit board, so that the layout is flexible, the height space occupied on the circuit board 100 is saved, the corresponding size of the driver is saved, and the power density of the driver is improved (i.e. more power devices can be installed). Along with the development of MOS tube technology, a switching device with voltage-resisting capability meeting the requirements of a switching power supply can be selected as the first switching device Q1.

In this embodiment, the distance between the first switching device Q1 and the circuit board 100 (compared with the switching device in the form of an interposer) is shorter, and the first switching device Q1 can more conveniently dissipate heat by using the circuit board 100, which is beneficial to improving the heat dissipation efficiency of the first switching device Q1 and the switching power supply.

Further as an alternative embodiment, referring to fig. 3 and 4, the switching power supply may further include a heat sink 300, for example, an aluminum profile heat sink, a heat sink with a temperature equalizing plate, etc., which is not limited in this embodiment. A side (top surface in the drawing) of the first switching device Q1 facing away from the circuit board 100 abuts against the heat sink 300.

The radiator 300 can further improve the heat dissipation efficiency of the switching power supply; meanwhile, the first switching device Q1 and the radiator 300 fixed by the patch technology occupy a smaller volume as a whole, which is beneficial to further saving the volume of the corresponding driver and further improving the power density of the driver (i.e. more power devices can be installed).

Further as an alternative embodiment, referring to fig. 5, the switching power supply may further include a second switching device Q2, where the second switching device Q2 is configured to control on/off of a line where the primary winding Np is located, for example, by using a driving signal output by the control chip U0 (i.e., an output end of the control chip U0 is electrically connected to the controlled ends of the first switching device Q1 and the second switching device Q2, respectively) or by switching in another signal to control the switching power supply, which is not limited in this embodiment.

In one embodiment, the control chip U0 may be configured to include a PWM signal generating circuit, and an output terminal of the PWM signal generating circuit is connected to the controlled terminal of the first switching device Q1 and the controlled terminal of the second switching device Q2. Of course, the control chip U0 may be configured in other existing forms capable of controlling the on/off of the first switching device Q1 and the second switching device Q2, which is not limited in this embodiment. In addition, the second switching device Q2 may also be fixed to the circuit board 100 by a bonding process, such as using SMT (Surface Mounted Technology) materials, so that the second switching device Q2 is closer to the circuit board 100 (than the switching device in the form of an interposer).

In this embodiment, the second switching device Q2 can more conveniently dissipate heat by using the circuit board 100, which is beneficial to improving the heat dissipation efficiency of the second switching device Q2 and the switching power supply. It will of course be appreciated that the second switching device Q2 may also dissipate heat in other possible ways, such as: the heat dissipation by the connection radiator, the heat dissipation by natural wind by adopting the back-attached mode, and the like can be specifically determined according to practical situations, and the embodiment of the present specification is not limited thereto. When the second switching device Q2 radiates heat by being connected to the heat sink, the side of the second switching device Q2 facing away from the circuit board 100 may specifically be configured to abut against the heat sink 100.

Further, the second switching device Q2 is connected in series with the first switching device Q1, so that the heat dissipation efficiency is improved, the individual voltage division of the first switching device Q1 and the second switching device Q2 is reduced, and the service lives of the first switching device Q1 and the second switching device Q2 are prolonged. By connecting the two switching devices in series, the withstand voltage of the devices can be ensured to meet the specification.

In one embodiment, the circuit board 100 may include a metal layer, for example, the circuit board 100 may be configured as a PCB circuit board, and a copper foil layer on the PCB circuit board is the metal layer, i.e., the metal layer may be made of copper foil. The pin of the first switching device Q1 is fixedly connected with the metal layer, and the pin of the second switching device Q2 is fixedly connected with the metal layer. The PCB circuit board can be provided with a substrate layer, a copper foil layer and a solder mask layer which are sequentially stacked, wherein the substrate layer can be made of glass fiber, paperboard, aluminum substrate and the like; the copper foil layer is composed of a plurality of copper traces, bonding pads connected with the copper traces, and the like, and can be used as a metal layer in the circuit board 100; a solder mask (typically green or red or other color) covers the copper traces, preventing the copper traces from accidentally touching other metals, solders, etc., but leaving the pads exposed for soldering. At this time, the pins of the first switching device Q1 and the second switching device Q2 are soldered and fixed to the pads in the metal layer. Of course, the PCB circuit board can be provided with copper foil layers on both sides of the substrate layer; alternatively, the PCB may not be provided with the solder mask, which is not limited in this embodiment. The first and second switching devices Q1 and Q2 can dissipate heat through the metal layer of the circuit board 100 to further improve heat dissipation efficiency. Specifically, the first switching device Q1 and the second switching device Q2 may dissipate heat by directly contacting the pins with the metal layer, or may dissipate heat by radiating heat to the metal layer.

For the switching power supplies shown in fig. 1 and 5, the switching power supplies may further include a first resistor R1 and a chip power supply circuit 203, where the first resistor R1 is connected in parallel with the primary winding Np, and the first resistor R1 and the chip power supply circuit 203 are both connected to a power supply pin of the control chip U0; the chip power supply circuit 203 includes a power supply coil Na disposed opposite to the secondary side unit 202, the power supply coil Na being configured to supply power to the control pin of the control chip U0 by the formation of a back electromotive force by the secondary side unit 202. The first resistor R1 can supply power to the control chip U0 at the initial starting stage of the control chip U0, and power is supplied through the chip power supply circuit 203 in the operation process, so that the load of the first resistor R1 is reduced, and the overall durability of the switching power supply is improved.

The chip power supply circuit 203 may further include a second resistor R2, a unidirectional conducting element D0, a power supply coil Na, and a capacitor C0, where the second resistor R2, a negative electrode of the unidirectional conducting element D0, a positive electrode of the unidirectional conducting element D0, the power supply coil Na, and the capacitor C0 are sequentially connected end to end, and a common contact between the second resistor R2 and the capacitor C0 is connected to a power supply pin of the control chip U0.

The utility model also provides a driver, and the driver of the switching power supply. The specific structure of the switching power supply refers to the above embodiments, and since the driver adopts all the technical solutions of all the embodiments, the driver has at least all the beneficial effects brought by the technical solutions of the embodiments, and will not be described in detail herein.

The foregoing description is only of the preferred embodiments of the present utility model, and is not intended to limit the scope of the utility model, but rather, the equivalent structural changes made by the description and drawings of the present utility model or the direct/indirect application in other related technical fields are included in the scope of the present utility model.

Claims (10)

1. A switching power supply for use in a driver, the switching power supply comprising:

a circuit board;

the switching power supply module comprises a primary side unit and a secondary side unit;

the primary side unit comprises a control chip, a first switching device and a primary side coil, wherein the first switching device is connected in series with the primary side coil so as to control the on-off of the input voltage of the primary side coil through the on-off of the first switching device; the control chip is used for outputting a driving signal to a controlled end of the first switching device so as to control the on-off of the first switching device; the first switching device is fixed on the circuit board by adopting a surface mounting technology.

2. The switching power supply of claim 1 further comprising a second switching device, wherein the second switching device is configured to control on-off of a line on which the primary coil is located, and the second switching device is fixed on the circuit board by using a chip mounting process.

3. The switching power supply of claim 2 wherein said second switching device is connected in series with said first switching device, and wherein an output terminal of said control chip is electrically connected to a controlled terminal of said first switching device and said second switching device, respectively.

4. The switching power supply of claim 2 wherein said circuit board includes a metal layer, said pins of said first switching device being fixedly connected to said metal layer, said pins of said second switching device being fixedly connected to said metal layer.

5. The switching power supply of claim 4 wherein said metal layer is made of copper foil.

6. The switching power supply according to any one of claims 1 to 5, further comprising a heat sink, wherein a side of the first switching device facing away from the circuit board abuts the heat sink.

7. The switching power supply of claim 6 wherein, in the case where said switching power supply further includes a second switching device, a side of said second switching device facing away from said circuit board abuts said heat sink.

8. The switching power supply as claimed in any one of claims 1 to 5, further comprising a first resistor and a chip power supply circuit, wherein the first resistor is connected in parallel with the primary coil, and the first resistor and the chip power supply circuit are both connected to a power supply pin of the control chip; the chip power supply circuit comprises a power supply coil, wherein the power supply coil is arranged opposite to the secondary side unit, and the power supply coil is used for supplying power to a control pin of the control chip through the formation of reverse electromotive force by the secondary side unit; the chip power supply circuit further comprises a second resistor, a unidirectional conduction element, a power supply coil and a capacitor, wherein the second resistor, the negative electrode of the unidirectional conduction element, the positive electrode of the unidirectional conduction element, the power supply coil and the capacitor are connected end to end in sequence, and a common contact point between the second resistor and the capacitor is connected with a power supply pin of the control chip.

9. A switching power supply according to any one of claims 2 to 5, wherein the control chip comprises a PWM signal generating circuit, the output of which is connected to the controlled end of the first switching device and/or the second switching device.

10. A driver, characterized in that the driver comprises a switching power supply as claimed in any one of claims 1 to 9.