Buck Converter

Abstract

To provide a buck converter that reduces the area used, minimizes parasitic inductance, minimizes transfer impedance, reduces and minimizes step-down paths, and can be applied to a wide variety of fields without additional structural modifications. [Solution] The buck converter Z1 of the present invention includes a power module 1 and an inductor element 2. The power module includes a lead frame 11, a first power element 12, a second power element 13, and a driver chip 14, with the first power element, second power element, and driver chip all mounted on the lead frame. The inductor element is located above the power module. First leads of the inductor element are electrically connected to the first power element and the second power element, respectively, and second leads of the inductor element are connected to the lead frame or are not in contact with the lead frame.

Description

[Technical Field]

[0001] The present invention relates to a buck converter, and more particularly to a buck converter having an inductor element and a metal oxide semiconductor field effect transistor (MOSFET). [Background technology]

[0002] With the advancement of science and technology, the size of semiconductor elements is becoming more precise and refined. Electronic products are moving towards miniaturization and higher power output. For example, in the case of buck converters, the driver chip, power element, inductor element, etc., in the conventional technology are designed in a planar structure. However, this structure requires a large ground area and does not meet the needs of miniaturization. In addition, high-power products also need to consider the circuit design and heat dissipation effect.

[0003] Therefore, how to improve the structural design of the buck converter and overcome the above drawbacks in order to improve the effect of the buck converter has become one of the important problems that the industry is trying to solve. Summary of the Invention

[0004] In view of this, the present invention provides a buck converter. The buck converter includes a power module and an inductor element. The power module includes a lead frame, a first power element, a second power element, and a driver chip, all of which are mounted on the lead frame. The inductor element is located above the power module. First leads of the inductor element are electrically connected to the first power element and the second power element, respectively, and second leads of the inductor element are connected to the lead frame, or the second leads of the inductor element do not contact the lead frame. [Brief explanation of the drawings]

[0005] [Figure 1] 1 is a schematic view showing the appearance of a buck converter according to an embodiment of the present invention; [Figure 2] FIG. 2 is an exploded schematic view of the embodiment shown in FIG. [Figure 3] FIG. 2 is an exploded schematic view of the embodiment shown in FIG. [Figure 4] 1 is a cross-sectional view of a buck converter according to an embodiment of the present invention; [Figure 5] 1 is a cross-sectional view of a buck converter according to an embodiment of the present invention; [Figure 6] 1 is a cross-sectional view of a buck converter according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0006] Referring to Figures 1 to 3, Figure 1 is a schematic view of the appearance of a buck converter Z1 according to an embodiment of the present invention, Figure 2 is an exploded schematic view of the embodiment shown in Figure 1, and Figure 3 is an exploded schematic view of the embodiment shown in Figure 1.

[0007] The buck converter Z1 includes a power module 1 and an inductor element 2. The power module 1 includes a lead frame 11, a first power element 12, a second power element 13, and a driver chip 14. The first power element 12, the second power element 13, and the driver chip 14 are all mounted on the lead frame 11. In some embodiments, the power module 1 is a Dr-MOS, the first power element 12 may be defined as a high-side MOSFET, and the second power element 13 may be defined as a low-side MOSFET. The first power element 12, the second power element 13, and the driver chip 14 are electrically connected to each other (for example, by wires (see the diagram below) or by providing pads). The inductor element 2 is located above the power module 1. A first lead 21 of the inductor element 2 is electrically connected to the first power element 12 and the second power element 13, respectively, and a second lead 22 of the inductor element 2 is connected to the lead frame 11. In some embodiments, the second lead 22 of the inductor element 2 may be connected to the lead frame 11, or the second lead 22 of the inductor element 2 may not contact the lead frame 11, and the end of the second lead 22 may be inserted into a circuit board.

[0008] Referring to FIG. 4, FIG. 4 is a cross-sectional view of a buck converter Z2 according to an embodiment of the present invention. In this embodiment, the power module 1 includes a package 4 that covers a lead frame 11, a first power element 12, a second power element 13, and a driver chip 14. The lead frame 11 includes a conductive member 111 (see FIGS. 2 and 3). The driver chip 14 is electrically connected to the conductive member 111 via a conductor 15 and to the first power element 12 via another conductor 15. In addition, in the embodiment of FIGS. 1 and 4, the buck converters Z1 and Z2 further include a connector 3 made of a metal material. The first lead 21 is electrically connected to the first power element 12 and the second power element 13 via the connector 3. The connector 3 is, for example, a copper plate or copper foil, and may be used in a copper clip package during manufacturing.

[0009] 5, which is a cross-sectional view of a buck converter Z3 according to an embodiment of the present invention. In this embodiment, the end of the second lead 22 is exposed to the outside of the lead frame 11 and can be inserted into a circuit board as a lead.

[0010] Referring to Figure 6, Figure 6 is a schematic cross-sectional view of a buck converter Z4 according to an embodiment of the present invention. In this embodiment, the first lead 21 is in direct electrical contact with the first power element 12 and the second power element 13, and the end of the second lead 22 is connected to the conductive member 111. The package 4 covers the inductor element 2, the first power element 12, the second power element 13, the driver chip 14, and the lead frame 11.

[0011] According to some embodiments, the inductor element 2 further includes an iron core 23. The first lead 21 is exposed to a surface 231 of the iron core 23. According to the embodiments of Figures 4 and 5, the first lead 21 serves to conduct high-temperature heat generated in the power module 1 to the outside. Furthermore, the second lead 22 is connected to the first lead 21 and is exposed to the surface 231 of the iron core 23. In this way, the first lead 21 can conduct high-temperature heat to the second lead 22, and from there to the outside.

[0012] It should be noted that a buck converter does not only include one set of power module 1 and inductor element 2, but in some embodiments, a buck converter includes multiple power modules 1 and (correspondingly stacked) inductor elements 2. [Beneficial Effects of Examples]

[0013] One of the beneficial effects of the present invention is that the buck converter of the present invention, in some embodiments, reduces the area required (design) of the buck converter, and the stacked structure design of the inductor element and the power module reduces the area required for the inductor element and the power module, in some embodiments, the area required can be reduced by at least 50%.

[0014] One beneficial effect of the present invention is that the buck converter according to the present invention, in an embodiment, minimizes the parasitic inductance in the path from the power element to the inductor element, thereby minimizing the transfer impedance.

[0015] One of the beneficial effects of the present invention is that the buck converter according to the present invention, in an embodiment, reduces and minimizes the step-down path.

[0016] One of the beneficial effects of the present invention is that the buck converter of the present invention, in its embodiments, uses a packaging method for the driver chip and the MOSFET, and a method in which the second lead of the inductor element is connected to the lead frame or the second lead of the inductor element is not in contact with the lead frame, so that the buck converter does not need to be modified in structure to be applied to a wide range of applications.

[0017] One of the beneficial effects of the present invention is that in the embodiment of the buck converter of the present invention, an inductor element is connected to the first power element and the second power element, so that the high temperature heat of the first power element and the second power element can be dissipated through at least one of the first lead and the second lead of the inductor element, and can also be guided to the outside through the lower lead frame. [Explanation of symbols]

[0018] Z1 to Z4: Buck converters 1: Power module 11: Lead frame 111: Conductive member 12: First power element 13: Second power element 14: Driving chip 15: Conductor 2: Inductor element 21: First lead 22: Second Lead 23: Iron core body 231: Surface 3: Connector 4:Package

Claims

1. a power module including a lead frame, a first power element, a second power element, and a driving chip, wherein the first power element, the second power element, and the driving chip are all mounted on the lead frame; an inductor element located above the power module, a first lead of the inductor element electrically connected to the first power element and the second power element, respectively, and a second lead of the inductor element connected to the lead frame, or the second lead of the inductor element does not contact the lead frame.

2. 2. The buck converter of claim 1, wherein the lead frame includes at least one conductive member, and the driver chip is electrically connected to the conductive member via a conductor and to the first power device via another conductor.

3. The buck converter of claim 1 , further comprising a connector made of a metal material, wherein the first lead is electrically connected to the first power element and the second power element through the connector.

4. The buck converter of claim 1 , wherein the first lead is made of a metal material and is electrically connected to the first power element and the second power element in contact with each other.

5. The buck converter according to claim 1 , wherein the inductor element further includes an iron core, and the first lead is exposed on a surface of the iron core.

6. The buck converter according to claim 5 , wherein the second lead is connected to the first lead and is exposed on the surface of the core body.

7. The buck converter according to claim 1 , wherein the power module and the inductor element are plural.

Images