Power semiconductor module with an overcurrent detection unit

Abstract

Power semiconductor module with a substrate arranged in a housing (4), wherein an overcurrent detection circuit (5) and a power semiconductor switch (T1) with its load current input (10) is arranged on the substrate inside the housing (4), wherein the overcurrent detection circuit (5) is electrically connected to the load current input (10), wherein the power semiconductor switch (T1) further comprises a load current output (12) and a control input (14), and with a control device (2) arranged outside the housing with a limit monitoring unit (6), wherein the control device (2) is electrically connected to the control input (14), and with a limit monitoring unit (6) which is electrically connected to the overcurrent detection circuit (5), wherein the overcurrent detection circuit (5) comprises a second electrical resistor (R2), a diode (D1) and a Zener diode (Z1), wherein the diode (D1) is configured as a series connection of a plurality of sub-diodes (D1,D2), wherein the cathode of the diode (D1) is connected to the load current input (10), the anode of the diode is connected to a first contact of the second electrical resistor (R2) and the second contact of the second electrical resistor (R2) is connected to a first input of the limit monitoring unit (6) and the cathode of the Zener diode (Z1), and wherein the anode of the Zener diode (Z1) is connected to the load current output (12).

Description

[0001] The invention describes a power semiconductor module with a substrate arranged in a housing, wherein an overcurrent detection circuit and a power semiconductor switch with its load current input are arranged on the substrate inside the housing.

[0002] DE 10 2014 110 768 B3 discloses a power semiconductor circuit with a power semiconductor switch, a control device and an overcurrent detection circuit, wherein the overcurrent detection circuit has a limit monitoring unit and a first and a second capacitor.

[0003] In light of the aforementioned circumstances, the invention aims to provide a power semiconductor module with an optimized overcurrent detection circuit that requires little space.

[0004] This problem is solved according to the invention by a power semiconductor module with a substrate arranged in a housing, wherein an overcurrent detection circuit and a power semiconductor switch with its load current input are arranged on the substrate inside the housing, wherein the overcurrent detection circuit is electrically connected to the load current input, wherein the power semiconductor switch further comprises a load current output and a control input, and with a control device arranged outside the housing, comprising a limit monitoring unit, wherein the control device is electrically connected to the control input, and with a limit monitoring unit that is electrically connected to the overcurrent detection circuit, wherein the overcurrent detection circuit (5) comprises a second electrical resistor (R2), a diode (D1) and a Zener diode (Z1), wherein the diode (D1) is a series connection of a plurality of sub-diodes (D1,D2) is configured, wherein the cathode of the diode (D1) is connected to the load current input (10), the anode of the diode is connected to a first contact of the second electrical resistor (R2), and the second contact of the second electrical resistor (R2) is connected to a first input of the limit monitoring unit (6) and the cathode of the Zener diode (Z1), and wherein the anode of the Zener diode (Z1) is connected to the load current output (12)..,

[0005] It is preferred that the border monitoring unit is configured to generate an overcurrent detection signal when the electrical voltage at the first input of the border monitoring unit exceeds a reference voltage applied to the second input of the border monitoring unit.

[0006] Furthermore, it is preferred that the control device is configured to generate a control voltage to switch off the power semiconductor switch upon receipt of the overcurrent detection signal.

[0007] It can also be advantageous if the diode and the second electrical resistor are arranged on a first conductor track and the Zener diode on a second conductor track.

[0008] It can also be advantageous if the overcurrent detection circuit is designed as an integrated circuit, particularly an unhoused one.

[0009] It can also be advantageous if the power semiconductor switch and the overcurrent detection circuit are metallurgically bonded to the first conductor track. It can be advantageous if the metallurgical bond is formed as an adhesive, sintered, or soldered connection.

[0010] Of course, unless explicitly or per se excluded or contrary to the idea of ​​the invention, the features or groups of features mentioned in the singular may be present multiple times in the assembly or power semiconductor device according to the invention.

[0011] It is understood that the various embodiments of the invention can be implemented individually or in any combination to achieve improvements. In particular, the features mentioned and explained above and below can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the present invention.

[0012] Further explanations of the invention, advantageous details and features, will become apparent from the following description of the invention contained in the Fig. 1 to Fig. 2 schematically illustrated embodiments of the invention, or of respective parts thereof. Fig. Figure 1 shows a section of a power semiconductor circuit of a power semiconductor module according to the invention. Fig. Figure 2 shows an embodiment of a power semiconductor circuit of a power semiconductor module according to the invention.

[0013] Fig. Figure 1 shows a section of an embodiment of a power semiconductor circuit 1 of a power semiconductor module 4 according to the invention.

[0014] Fig. Figure 1 shows a section of a power semiconductor circuit 1 of a power semiconductor module according to the invention. This module comprises a control unit 3 and a housing 4. The power semiconductor circuit 1 further comprises an overcurrent detection circuit 5 and a power semiconductor switch T1. The overcurrent detection circuit 5 and a load current input 10 of the power semiconductor switch T1 are arranged on a substrate within the housing 4 of the power semiconductor module and are electrically connected to each other. The power semiconductor switch T1 further comprises a load current output 12 and a control input 14, which are also arranged in the housing 4. The control unit 3 comprises a control device 2, cf. Fig. 2, a limit monitoring unit 6, a first electrical resistor R1, and a first capacitor C1. The control unit 3 is arranged outside the housing 4. A first input of the limit monitoring unit 6, a first terminal of the first capacitor C1, a first terminal of the overcurrent detection circuit 5, and a first terminal of the first resistor R1 are electrically connected via an electrical junction 7. A second terminal of the first capacitor C1 is electrically connected to the load current output 12 of the power semiconductor switch T1 and to a second terminal of the overcurrent detection circuit 5. The control unit 2 is designed to control the power semiconductor switch T1 and is electrically connected to its control input 14. For this purpose, the control unit 2 generates a control signal 9, see Figure 1. Fig. 2, which is generated, for example, by a higher-level control system (not shown), a control voltage Ua at the control input 14 of the power semiconductor switch T1. The power semiconductor switch T1 is switched on and off depending on the level of the control voltage Ua.

[0015] The power semiconductor switch T1 is implemented here as an IGBT. For example, it can also be formed from a plurality of IGBTs connected in parallel. The collector terminal of each IGBT then forms the load current input, the emitter terminal the load current output, and the gate terminal the control input. Alternatively, the power semiconductor switch T1 can also be implemented as a MOSFET, preferably a wide-bandgap MOSFET, i.e., a SiC or GaN MOSFET, or as a parallel connection of MOSFETs. In this case, the drain terminal forms the load current input, the source terminal the load current output, and the gate terminal the control input.

[0016] Fig. Figure 2 shows a detailed embodiment of a power semiconductor circuit 1 of a power semiconductor module according to the invention. Fig. 2 differs from Fig.Figure 1 shows the control device 2 described above. Furthermore, the overcurrent detection circuit 5 includes, by way of example, a second electrical resistor R2, a first and a second fast-switching diode D1, D2 with low junction capacitance, and a Zener diode Z1 with, for example, 15V. The cathode of the second diode D2 is connected to the load current input 10, and the anode of the first diode D1 is connected to the first terminal of the second electrical resistor R2. The first and second diodes D1, D2 are therefore connected in series. The second terminal of the second electrical resistor R2 is electrically connected to the first input of the limit monitoring unit 6 and to the cathode of the Zener diode Z1. Furthermore, the anode of the Zener diode Z1 is electrically connected to the load current output 12 of the power semiconductor switch T1 and to the second terminal of the first capacitor C1.

[0017] Alternatively, the overcurrent detection circuit 5 can also consist of only one diode or be configured as a series circuit of multiple partial diodes, more than two. The two diodes D1 and D2 and the second electrical resistor R2 are shown here, by way of example, arranged on a first conductor track of the substrate and bonded together by sintering. The Zener diode Z1 is also shown, purely by way of example, arranged on a second conductor track of the substrate and bonded to it by soldering. Alternatively, the respective connections could also be made of a different type of bond, such as an adhesive bond.

[0018] The limit monitoring unit 6 generates an overcurrent detection signal 8 when the electrical second voltage U2 at the first input of the limit monitoring unit 6 exceeds a reference voltage Ur applied to the second input of the limit monitoring unit 6. The overcurrent detection signal 8 is supplied to the control unit 2 as an input signal. If the power semiconductor switch T1 is switched on, the control unit 2 switches off the power semiconductor switch T1 upon receiving the overcurrent detection signal 8.

[0019] If the current I1 flowing through the power semiconductor switch T1 becomes very high when the power semiconductor switch T1 is switched on, e.g., in the event of a short circuit, the voltage U1 between the first and second load current inputs 10 and the load current output 12 rises sharply. This results in a brief transient current flow through the first capacitor C1, charging the first capacitor C1 and increasing the electrical voltage U2. If the electrical voltage U2 at the first input of the limit monitoring unit 6 exceeds the reference voltage Ur at the second input of the limit monitoring unit 6, the limit monitoring unit 6 generates the overcurrent detection signal 8 and supplies it to the control device 2 as an input signal.The control device 2 switches off the power semiconductor switch T1 upon receipt of the overcurrent detection signal 8 and thus protects the power semiconductor switch T1 from the overcurrent flowing through it. Reference sign 1 Power semiconductor circuit 2 Control unit 3 Control unit 4 cases 5 Overcurrent detection circuit 6 Border surveillance unit 7 Junction 8 Overcurrent detection signal 9 Control signal 10 Load current input 12 Load current output 14 Tax receipt C1 first capacitor D1 first diode D2 second diode I1 Electricity R1 first electrical resistor R2 second electrical resistor T1 Power semiconductor switch U1 first voltage U2 second voltage Ua control voltage Ur reference voltage

Claims

[1] Power semiconductor module with a substrate arranged in a housing (4), wherein an overcurrent detection circuit (5) and a power semiconductor switch (T1) with its load current input (10) is arranged on the substrate inside the housing (4), wherein the overcurrent detection circuit (5) is electrically connected to the load current input (10), wherein the power semiconductor switch (T1) further comprises a load current output (12) and a control input (14), and with a control device (2) arranged outside the housing with a limit monitoring unit (6), wherein the control device (2) is electrically connected to the control input (14), and with a limit monitoring unit (6) which is electrically connected to the overcurrent detection circuit (5), wherein the overcurrent detection circuit (5) comprises a second electrical resistor (R2), a diode (D1) and a Zener diode (Z1), wherein the diode (D1) is configured as a series connection of a plurality of sub-diodes (D1,D2), wherein the cathode of the diode (D1) is connected to the load current input (10), the anode of the diode is connected to a first contact of the second electrical resistor (R2) and the second contact of the second electrical resistor (R2) is connected to a first input of the limit monitoring unit (6) and the cathode of the Zener diode (Z1), and wherein the anode of the Zener diode (Z1) is connected to the load current output (12). [2] Power conductor module according to claim 1, wherein the limit monitoring unit (6) is configured to generate an overcurrent detection signal (8) when the electrical voltage at the first input of the limit monitoring unit (6) exceeds a reference voltage (Ur) applied at the second input of the limit monitoring unit (6). [3] Power semiconductor module according to claim 2, wherein the control device (2) is configured to generate a control voltage (Ua) to switch off the power semiconductor switch (T1) upon receipt of the overcurrent detection signal (8). [4] Power semiconductor module according to claim 3, wherein the diode and the second electrical resistor (R2) are arranged on a first conductor track and the Zener diode (Z1) is arranged on a second conductor track. [5] Power semiconductor module according to one of claims 1 to 3, wherein the overcurrent detection circuit (5) is designed as an integrated circuit, in particular an unhoused one. [6] Power semiconductor module according to one of the preceding claims, wherein the power semiconductor switch (T1) and the overcurrent detection circuit (5) are metallurgically connected to the first conductor track. [7] Power semiconductor module according to claim 6, wherein the material-bonded connection is formed as an adhesive, sintered or soldered connection.

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