JPH09172359A - Gate circuit for voltage driven semiconductor switching element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the current balance in a chip by connecting each gate resistor suitable for an on-characteristic and an off-characteristic of a voltage driven semiconductor switching element between a gate drive circuit and a gate terminal respectively. SOLUTION: The voltage drive semiconductor switching element IEGT (SD) is formed by containing plural chips ch1-chn in one package, connecting anodes, cathodes, gates of each chip in common respectively and leading out an anode terminal A, a cathode terminal K and a gate terminal G as external terminals. Then a gate resistor RP whose resistance is suitable for an on-characteristic of the IEGT (SD) is connected between a gate drive circuit 1 and the gate terminal G via a diode DP and a gate resistor RN whose resistance is suitable for an off-characteristic of the IEGT (SD) is connected between the gate drive circuit 1 and the gate terminal G via a diode DN. Thus, the IEGT(SD) is controlled by using the suitable resistor RP (RN) for the ON (OFF) state respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage-driven semiconductor switching element (In
injection Enhanced Gate Tra
The present invention relates to a gate circuit of a voltage-driven semiconductor switching element that improves the current balance during switching of a transistor (hereinafter simply referred to as IEGT) to improve switching characteristics.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional IEGT gate control circuit. In the figure, reference numeral 1 is a gate drive circuit, and the gate drive circuit 1 outputs a voltage of, for example, +15 V when turned on according to an output signal of a control circuit (not shown).
The GT (SD) is turned on, and when it is off, a voltage of -15 V is output to turn off the IEGT (SD). At this time, the gate resistance R was commonly controlled by one. A is an anode terminal, G is a gate terminal, and K is a cathode terminal.

Here, as shown in FIG. 5, the IEGT (SD) is formed by connecting a large number of relatively small chips ch1 to chn in parallel, and as a result, a large capacity IEGT (SD) is produced.
Since a large number of chips ch1 to chn are connected in parallel in these elements, it is necessary to improve the current balance, and measures such as making the voltages at the on-time equalized were taken. Chips ch1 to chn
The current balance between them was bad.

[0004]

As described above, the IE with the same gate resistance R at the time of turning on and off like the conventional gate control circuit.
When the GT (SD) is driven, the current balance of the chips ch1 to chn at the time of switching is not improved.

Therefore, an object of the present invention is to provide a gate circuit of a voltage drive type semiconductor switch capable of improving the current balance of each of the chips ch1 to chn at the time of turning on and off and improving the switching characteristics. To do.

[0006]

In order to achieve the above object, a gate circuit of a voltage-driven semiconductor switching element according to a first aspect of the present invention comprises a plurality of chips connected in parallel and a common anode terminal. In a voltage-driven semiconductor switching element having a cathode terminal and a gate terminal,
A means for connecting a gate resistance suitable for each of the ON characteristic and the OFF characteristic of the voltage driven type semiconductor switching element between the gate driving circuit of the voltage driven type semiconductor switching element and the gate terminal. .

Further, in order to achieve the above-mentioned object, claim 2
According to another aspect of the present invention, there is provided a gate circuit for a voltage-driven semiconductor switching device, wherein a plurality of chips are connected in parallel to have a common anode terminal and a common cathode terminal, and each gate independently has a gate terminal. In the above, the device further comprises means for connecting a gate resistance suitable for each of the on-characteristic and the off-characteristic of each chip between the gate driving circuit of the voltage driving type semiconductor switching element and each of the gate terminals. To do.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a first embodiment of a gate circuit of a voltage-driven semiconductor switching device according to the present invention will be described with reference to the block diagram of FIG. In FIG. 1, reference numeral 1 denotes a gate drive circuit of the IEGT (SD), which outputs a voltage of, for example, +15 V when the IEGT (SD) is on and outputs a voltage of −15 V when the IEGT (SD) is on, according to a control circuit (not shown).
A voltage of 15 V is output to control the on / off of IEGT (SD). ch1 to chn are IEGT chips ch1
~ Chn, a plurality of chips ch1 to chn are accommodated in one package, and an anode, a cathode of each chip,
The gates are commonly connected to each other, and the anode terminal A, the cathode terminal K, and the gate terminal G are led as external terminals to form an IEGT (SD).

IEGT (SD) constructed as described above
In, the gate resistance RP suitable for the ON characteristic of IEGT (SD) is connected between the gate drive circuit 1 and the gate terminal G via the diode DP, and the gate resistance RN suitable for the OFF characteristic of IEGT (SD) is The gate drive circuit 1 and the gate terminal G are connected via a diode DN.

Therefore, since the IEGT (SD) is controlled by the gate resistances RP and RN suitable for ON and OFF, the current balance at the time of switching the chip inside the IEGT (SD) can be improved. .

Next, a second embodiment of the gate circuit of the voltage-driven semiconductor switching element according to another embodiment of the invention described in claim 1 is shown in FIG. Description will be made with reference to the configuration diagram of FIG.

In the embodiment shown in FIG. 2, the IEGT (S
D) chips ch1 to chn have internal gate resistance Rch1
~ Rchn are connected in advance (may be created by a process).

As a result, the internal gate resistances Rch1 to Rchn further reduce the difference between the chips as compared with the case where the gate resistances RP and RN are connected only to the outside as shown in FIG. 1, so that the current balance during switching is further improved. To be done.

Next, a third embodiment of the gate circuit of the voltage-driven semiconductor switching device according to the second embodiment of the invention will be described with reference to the block diagram of FIG. In FIG. 3, reference numeral 1 denotes a IEGT (SD) gate drive circuit, which outputs a voltage of, for example, +15 V when the IEGT (SD) is on and outputs a voltage of −15 V when the IEGT (SD) is on, according to a control circuit (not shown).
A voltage of 15 V is output to control the on / off of IEGT (SD). ch1 to chn are IEGT (SD) chips, and a plurality of chips ch1 to chn are housed in one package, and the anode and cathode of each chip ch1 to chn are commonly connected to each other to form an anode terminal A and a cathode terminal K. As the external gate terminals G1 to Gn, and the gate G is also independently derived as I
Configure EGT (SD).

In this embodiment, the gate terminals G1 to Gn are derived from the chips ch1 to chn of the IEGT (SD),
Gate resistance RP1 suitable for on-state of IEGT (SD)
To RPn are connected between the gate drive circuit 1 and the respective gate terminals G1 to Gn via diodes DP1 to DPn, and the gate resistances RN1 to RNn suitable for the off characteristics of the IEGT (SD) are the gate drive circuit 1 And the diodes DN1 to DNn between the respective gate terminals G1 to Gn.
Connect through.

By configuring as described above, the IE
When the GT (SD) is turned on, the chip ch1 is turned on through the diode DP1 and the gate resistor RP1, and similarly, the chip chn is turned on through the diode DPn and the gate resistor RPn. That is, all chips are turned on independently.

On the other hand, when off, the chip ch1 is turned off through the diode DN1 and the gate resistor Rn1, and similarly, the chip chn is turned off through the diode DNn and the gate resistor RNn. That is, all chips are turned off independently.

Further, since the gate resistance is changed when each of the chips ch1 to chn is turned on and off, it can be freely set so that the current balance is good both when turned on and when turned off. For example, if the gate resistance is large at the time of turning off, the mirror effect varies among the chips, and the elements turning off early turn off quickly, so that the current concentrates on the chips that are slowing and the current becomes unbalanced. Therefore, the off current can be driven with a relatively low resistance to reduce the influence of the variation in the mirror effect time difference, thereby improving the current balance during the off time.

On the other hand, at the time of turning on, the current is imbalanced at the time of turning on by driving with a relatively large resistance to lengthen the mirror effect and reduce the influence of the time difference at the time of turning on.

As described above, when each chip ch1 to chn of the IEGT (SD) is connected in parallel, each chip ch1 to chn
chn can be controlled independently, so each chip ch1 ~ ch
The current balance of n can be optimally set at both on and off.

In the above description, the chip-level current variation of IEGT (SD) has been described, but the same applies to the current balance between elements when a large number of elements are connected in parallel.

Finally, a fourth embodiment of the gate circuit of the voltage-driven semiconductor switching device according to another embodiment of the invention described in claim 2 is shown in FIG. This will be described with reference to the configuration diagram of FIG.

In the embodiment shown in FIG. 4, the internal gate resistors Rch1 to Rch1 to the chips ch1 to chn are different from those in the embodiment shown in FIG.
Since the Rchn is connected, the difference between the chips ch1 to chn is further reduced, so that the current balance at the time of switching can be further improved. In the embodiment of FIGS. 3 and 4, the diodes DP1 to DPn may be shared by one, or the diodes DN1 to DNn may be shared by one.

[0024]

As described above, according to the present invention, when a large number of chips in a switching element are connected in parallel by a simple method, the current balance in the chip is improved both when the chip is on and when it is off. The rate is improved and the reliability can be increased.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment according to the invention of claim 1.

FIG. 2 is a configuration diagram showing a second embodiment according to another embodiment of the invention of claim 1.

FIG. 3 is a configuration diagram showing a third embodiment according to the invention of claim 2.

FIG. 4 is a configuration diagram showing a fourth embodiment according to another embodiment of the invention of claim 2;

FIG. 5 is a configuration diagram of a gate circuit of a conventional voltage-driven semiconductor switching element.

[Explanation of symbols]

1 ... Gate drive circuit DP1
DPn ... Diodes DN1 to DNn ... Diodes RP1
RPn ... Gate resistance RN1 to RNn ... Gate resistance G
… Gate terminals G1 to Gn… Gate terminals A
… Anode terminal K… Cathode terminal ch1
chn ... Chip SD ... Voltage driven semiconductor device

Claims (2)

[Claims] 1. A voltage-driven semiconductor switching device having a plurality of chips connected in parallel and having a common anode terminal, cathode terminal, and gate terminal. A gate circuit for a voltage-driven semiconductor switching device, comprising means for connecting a suitable gate resistor between the gate drive circuit for the voltage-driven semiconductor switching device and the gate terminal. 2. A voltage-driven semiconductor switching device having a plurality of chips connected in parallel and having a common anode terminal and cathode terminal and independently a gate terminal for each of the chips, on-characteristics and off-characteristics of each chip. A gate circuit for a voltage-driven semiconductor switching element, comprising means for connecting a gate resistor suitable for each of the above between a gate drive circuit of the voltage-driven semiconductor switching element and each of the gate terminals.