POWER MODULE

Abstract

The present disclosure provides power module, comprising at least three non-jumping power terminals at a non-jumping potential, wherein multiple power devices and at least one first capacitor are electrically connected between a first non-jumping power terminal and a second non-jumping power terminal of the at least three non-jumping power terminals; and at least one jumping power terminal at a jumping potential. A first jumping power terminal of the at least one jumping power terminal is electrically connected to one terminal of a power inductor and a third non-jumping power terminal of the at least three non-jumping power terminals is electrically connected to the other terminal of the power inductor; wherein at least one second capacitor is electrically connected between the third non-jumping power terminal and at least one of other non-jumping power terminals.

Claims

1. A power module, comprising: at least three non-jumping power terminals at a non-jumping potential, wherein multiple power devices and at least one first capacitor are electrically connected between a first non-jumping power terminal and a second non-jumping power terminal of the at least three non-jumping power terminals; and at least one jumping power terminal at a jumping potential, wherein a first jumping power terminal of the at least one jumping power terminal is electrically connected to one terminal of a power inductor and a third non-jumping power terminal of the at least three non-jumping power terminals is electrically connected to the other terminal of the power inductor; wherein at least one second capacitor is electrically connected between the third non-jumping power terminal and at least one of other non-jumping power terminals of the at least three non-jumping power terminals.

2. The power module according to claim 1, wherein a terminal of the second capacitor that is electrically connected to the third non-jumping power terminal is further provided with an auxiliary terminal, the auxiliary terminal being electrically connected to a terminal of an external capacitor.

3. The power module according to claim 1, wherein the first non-jumping power terminal is used as a reference point at a reference potential; and the jumping power terminal has a high-low level jumping with respect to the reference point with a voltage rising rate greater than 10V/us.

4. The power module according to claim 3, wherein the non-jumping power terminal is at a fixed potential with respect to the reference point; or has a sinusoidal ripple with a frequency less than 10 kHz with respect to the reference point with the voltage rising rate less than 2V/us; or is provided with an AC voltage with a frequency less than 10 KHz with respect to the reference point.

5. The power module according to claim 3, wherein the first capacitor and the second capacitor are high frequency capacitors.

6. The power module according to claim 1, wherein the value of the second capacitor is greater than 1 nF.

7. The power module according to claim 1, wherein the second capacitor is a Surface Mount Capacitor (SMC) or a capacitor die.

8. The power module according to claim 1, wherein the multiple power devices include at least one bridge arm, and each bridge arm includes at least two power devices connected in series.

9. The power module according to claim 1, wherein the power module is a high frequency switching power module.

10. The power module according to claim 8, wherein the first jumping power terminal of the at least one jumping power terminal is a center point of the bridge arm.

11. The power module according to claim 1, wherein the at least three non-jumping power terminals further includes a fourth non-jumping power terminal, wherein at least one third capacitor is electrically connected between the fourth non-jumping power terminal and at least one of other non-jumping power terminals excluding the third non-jumping power terminal among the at least three non-jumping power terminals.

12. The power module according to claim 1, wherein the at least three non-jumping power terminals further includes a fifth non-jumping power terminal, the fifth non-jumping power terminal and the third non-jumping power terminal being electrically connected.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] To make the above and other objects, features, advantages and examples of the invention more apparent and straightforward, a brief description of the drawings is provided as follows:

[0019] FIG. 1 is a schematic diagram of the structure of a conventional half-bridge power module;

[0020] FIG. 2 is a circuit schematic diagram of a conventional power module applied in the typical buck circuit;

[0021] FIG. 3 is a schematic diagram of the structure of a power module of the existing integrated high frequency capacitors;

[0022] FIG. 4 is a schematic diagram of an EMI analysis circuit of a conventional power module applied in a typical buck circuit;

[0023] FIG. 5 is a schematic diagram of the structure of a power module according to a preferred embodiment of the present invention;

[0024] FIGS. 6a-6c are voltage schematic diagrams of the non-jumping pin of FIG. 5 with respect to a reference point;

[0025] FIG. 7 is a schematic diagram of an EMI analysis circuit of a power module applied in a typical buck circuit according to the present invention.

[0026] FIG. 8 is a waveform schematic diagram obtained by performing RFI testing of the power module under a first-stage EMI filter according to the present invention.

[0027] FIGS. 9a-9h are schematic diagrams of a topology circuit of a power module according to another preferred embodiment of the present invention;

[0028] FIG. 10 is a schematic diagram of an optimized circuit of a power module according to another preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0029] In order to make the description of the invention more elaborate and complete, reference may be made to the accompanying drawings and the various examples described below, and the same numbers in the drawings represent the same or similar components. On the other hand, well-known components and steps are not described in the examples to avoid unnecessarily limiting the invention. In addition, some of the conventional structures and elements already known are shown in the drawings in a simplified schematic manner to simplify the drawings.

[0030] The power module of the present invention has at least three non-jumping power terminals and at least one jumping power terminal. Wherein, the at least three non-jumping power terminals are at non-jumping potentials, and multiple power devices and at least one first capacitor are electrically connected between a first non-jumping power terminal and a second non-jumping power terminal. At least one jumping power terminal is at a jumping potential. A first jumping power terminal is electrically connected to one terminal of a power inductor and a third non-jumping power terminal is electrically connected to the other terminal of the power inductor. And at least one second capacitor are electrically connected between the third non-jumping power terminal and at least one of other non-jumping power terminals.

[0031] In the present invention, the non-jumping potential generally refers to a potential, which is at fixed potential or has tiny high-low level jumping with respect to a reference potential point. The tiny high-low level jumping can be, for example, a voltage rising rate dv/dt less than 2V/us. The jumping potential generally refers to having a large high-low level jumping with respect to the reference potential point. The large high-low level jumping can be, for example, the voltage rising rate dv/dt greater than 10 V/us. In one embodiment, the threshold values of the above voltage rising rate dv/dt, such as 2V/us or 10V/us, may also be variable fluctuate within a certain range, such as, but not limited to, ten percent, or five percent of 2V/us or 10V/us etc.

[0032] As shown FIG. 5, in which shows a structure of a power module according to a preferred embodiment of the present invention. The power module M includes four power terminals, that is, terminals IN+, IN, AC and OUT. Wherein terminals IN+, IN and OUT are non-jumping power terminals at a non-jumping potential, and the terminal AC is jumping terminal at a jumping potential. In this embodiment, two power devices Q.sub.1 and Q.sub.2 and a capacitor C.sub.1 are electrically connected between terminals IN+ and IN. The above two power devices Q.sub.1 and Q.sub.2 are connected in series and configured as a bridge arm. The capacitor C.sub.1 is connected in parallel with this bridge arm, and terminals AC and OUT are used to respectively electrically connect to both two terminals of a power inductor, and a capacitor C.sub.2 is also electrically connected between terminals OUT and IN.

[0033] In this embodiment, terminals IN+, IN, AC, and OUT are respectively power terminals with current values greater than 1A. Wherein terminals IN+, OUT, and IN are terminals at a fixed potential, for example, the terminal IN serves as the reference point at a reference potential (such as a zero potential). Terminals IN+ and OUT are also at fixed potentials with respect to the terminal IN, which is shown in FIG. 6c. The terminal AC has a relative large high-low level jumping with respect to the terminal IN (reference point), that is, there is a relative large voltage rising rate dv/dt between AC and IN (for example, dv/dt>10V/us), which is the noise source of EMI. In other embodiments, terminals IN+, OUT, and IN may also be sinusoidal ripples superimposed with a frequency <10 kHz, and the voltage rising rate dv/dt is relatively small, such as less than 2V/us, as shown in FIG. 6b. In other embodiments, with respect to the terminal IN, the terminal OUT also may also be provided with an AC voltage with a frequency <10 kHz, which is also shown in FIG. 6a.

[0034] Preferably, in an embodiment of the invention, the capacitors C.sub.1, C.sub.2 may be high frequency capacitors. More preferably, the capacitor C.sub.2 can be a SMC or a capacitor die, and the value of the capacitor can be, for example, greater than 1 nF.

[0035] As shown FIG. 7, in which shows an EMI analysis circuit of a power module applied in a typical buck circuit according to the present invention. Wherein, with respect to the conventional power module M shown in FIG. 4, a power terminal OUT and a capacitor C.sub.2 are added to the power module M of the present invention, and the capacitor C.sub.2 is a high frequency capacitor with a parasitic inductance <1 nH. The value of the capacitor C.sub.2 is much larger than the parasitic capacitance C.sub.para1 of the power inductor L. The parasitic inductances L.sub.para1 and L.sub.para2 are relatively small, so in high frequency, the impedance at both terminals of A1A2 is approximately equal to the impedance ZC.sub.2 of the capacitor C.sub.2 and the voltage V.sub.A1A3 across A1A3 is approximated equals to V.sub.noise*ZC.sub.2/(ZC.sub.2+ZC.sub.para1). Since ZC.sub.2 is much smaller than ZC.sub.para1, the noise amplitude at across A1A3 is significantly reduced.

[0036] FIG. 8 is a waveform schematic diagram obtained by performing RFI testing on the power module under a first-stage EMI filter according to the present invention. Using the connection mode of the power module of the present invention, the waveform of the RFI is obtained from the test under the topology of the high-speed switching device GaN, as shown in FIG. 8. Seen from the waveform, the above power supply under first-level EMI filtering could satisfy the Class B standard.

[0037] It can be understood that the power module of the present invention is not limited to the above topology, and it can be widely applied to topologies such as boost, buck, Herric, and T-type three level, etc. At least one jumping node and at least three non-jumping nodes should be included in each topology. Moreover, the power terminal of the power module of the present invention in each topology should include both terminals of the power inductor and a non-jumping power terminal.

[0038] As shown FIGS. 9a to 9h, it shows topology circuits of the power modules according to other preferred embodiments.

[0039] As shown FIGS. 9a to 9b, the difference between the power module thereof and that shown in FIG. 5 is that: in the power module shown in FIG. 9a, the capacitor C.sub.2 is electrically connected between terminals OUT and IN+; In the power module shown in FIG. 9b, the capacitor C.sub.2 is electrically connected between terminals OUT and IN+, and the capacitor C.sub.3 is electrically connected between terminals OUT and IN.

[0040] As shown in FIG. 9c to FIG. 9e, the difference between the power module thereof and that shown in FIG. 5 is that: the power module shown in FIG. 9c to FIG. 9e includes two half-bridge arms between terminals IN+ and IN, which respectively includes power devices Q.sub.1 and Q.sub.2 connected in series, and Q.sub.3 and Q.sub.4 connected in series. And terminals AC1 and AC2 terminal at a jumping potential are the center points of the two half-bridge arms respectively. Moreover, in the power module shown in FIG. 9c, the capacitor C.sub.2 is electrically connected between terminals OUT and IN; in the power module shown in FIG. 9d, the capacitor C.sub.2 is electrically connected between terminals OUT and IN+. In the power module shown in FIG. 9e, the capacitor C.sub.2 is electrically connected between terminals OUT and IN+, and the capacitor C.sub.3 is electrically connected between terminals OUT and IN.

[0041] As shown in FIG. 9f to FIG. 9h, the difference between the power module thereof and that shown in FIG. 5 is that: the power module shown in FIG. 9f to FIG. 9h includes a full-bridge arm between terminals IN+ and IN, which includes power devices Q.sub.1, Q.sub.2, Q.sub.3 and Q.sub.4 connected in series. The power module further includes a first bridge arm having diodes D.sub.1 and D.sub.2 connected in series, which is connected in parallel with both terminals of the power devices Q.sub.2 and Q.sub.3. A second bridge arm having capacitors C.sub.1 and C.sub.2 connected in series is included between terminals IN+ and IN, and the terminal COM at a non-jumping potential is a center point of the first bridge arm and the second bridge arm. Also, in the power module shown in FIG. 9f, the capacitor C.sub.3 is electrically connected between the terminal OUT and the second bridge arm. In the power module indicated in FIG. 9g, the capacitor C.sub.3 is electrically connected between terminals OUT and IN+ terminals. In the power module indicated in FIG. 9h, the capacitor C.sub.3 is electrically connected between terminals OUT and IN.

[0042] As shown in FIG. 10, in order to better optimize the effect of EMI, the present invention can also add a power terminal OUT2 as an auxiliary terminal on the terminal of the capacitor C.sub.2, and the terminal OUT2 is electrically connected to the OUT1 terminal. The terminals AC and OUT1 are electrically connected at both terminals of the power inductor (such as the power inductor L in FIG. 7), and the terminal OUT2 is a non-jumping power terminal and is connected to one terminal of the external capacitor (such as capacitor C.sub.X1 in FIG. 7). This minimizes the equivalent inductance of C.sub.2, and compared with the power module shown in FIG. 5, EMI noise is less.

[0043] It can be understood that all the embodiments including the embodiment shown in FIG. 9a to FIG. 9h can change the output power terminal from one to two in the manner of FIG. 10, and those are not considered as the limitation of the present invention. Moreover, when making the layout of the power module shown in FIG. 5, in order to optimize EMI, one terminal of the power inductor and one terminal of the external capacitor may be respectively connected to the terminal OUT of the power module.

[0044] While the invention has been disclosed in the above implementations, it is not intended to limit the invention, and various modifications and retouches may be made by those skilled in the art without departing from the spirit and scope of the invention. The scope of protection of the invention therefore is subject to the scope defined by the appended claims.