JP2003324179A - Semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problems, in a power module for converting an output from a rectification circuit to an alternating current, that overheat protection is effected only to a particular element in the module, and that therefore overheat protection does not work in the case that an excessive current is permitted, at the time of failure, to flow through elements to which overheat protection is not effected. <P>SOLUTION: A semiconductor is provided with electrodes (11, 12) for connecting P, N electrodes of the rectification circuit and lines at P, N sides of the power module. The device is also provided with a temperature sensor (3) for one electrode (12), at the end of a power module connection side, for detecting the excessive current. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device such as a power module, and more particularly to a semiconductor device having a built-in overheat protection circuit.

[0002]

2. Description of the Related Art FIG. 3 shows an inverter circuit using a power module. 6 IGBTs (insulated-gat
e-bipolar-transistors) 1 power module 2
Converts the direct current from the rectifier circuit into alternating current of a desired frequency and supplies it to the three-phase motor M of the load. In order to protect the power module 2 from overheating, three IGs on the N side have been conventionally used.
A temperature sensor 3 for overcurrent detection is provided near one of the BTs 1n. If the temperature sensor 3 detects an overheated state, all the IGBTs 1 are switched off to protect the power module 2 from overload.

[0003]

For example, as shown in FIG. 3, when the motor M is in a locked state, a specific IGB
When a large current flows through T1 (chip indicated by ON), the IGBT 1 is not the target of temperature detection, and thus the temperature is not sensed, and there is a risk that the power module 2 is thermally destroyed.

The present invention provides a semiconductor device capable of reliably detecting the temperature rise of an element and performing reliable overheat protection.

[0005]

The present invention provides a semiconductor device, which is connected to first and second terminals (P, N) to which substantially direct current power is applied and which outputs multi-phase power. An overcurrent detection thermistor is provided on at least one of the first and second electrodes or in the vicinity of the electrode.

The overcurrent detecting thermistor is preferably arranged at at least one of the first and second electrodes at the semiconductor device connection side end of the electrode.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 shows an inverter circuit to which the power module 5 of the present invention is applied, and the internal structure of the power module 5 is shown in FIG. In FIGS. 1 and 2, reference numerals 11 and 12 denote the P and N poles of the rectifier circuit, respectively, and the IGBT 1 on the P side of the power module 5.
Electrodes (metal conductors) for connecting to the p-side and N-side IGBTs 1n, respectively. In FIG. 2, the right ends of these electrodes 11 and 12 are connected to the wiring patterns on the P side and the N side of the IGBT 1p and the IGBT 1n by soldering.

In this embodiment, the N-side electrode 12
The temperature sensor 3 is attached to the right end of the sheet using an adhesive. The mounting points are the points where the currents of the three IGBTs 1n flow, and since they are close to the IGBTs 1n, if any of the IGBTs 1n overheats, the heat is transferred to the end of the N-side electrode 12 through the wiring pattern or solder. Temperature rises.

With this configuration, when the motor M is operating normally, a substantially uniform current flows through each IGBT 1, so that the N-side electrode 12 does not rise in temperature so much, but when an excessive current flows through the motor M. IGBT1 overheats,
Therefore, the temperature of the end portion of the N-side electrode 12 rapidly rises. When the temperature detected by the temperature sensor 3 exceeds a predetermined value, each IG
BT1 is turned off, and the power module 5 stops operating.

In this case, even if any of the IGBTs 1n is overheated, the heat is transferred to the end portion, so that any rise in the temperature of the motor M can be detected and the overheat protection can be performed with high reliability.

When the temperature sensor 3 is provided on the P-side electrode 11, the temperature sensor 3 is attached at a position indicated by an arrow Q in the figure. Note that N
The temperature sensor 3 may be attached to both the side electrode 12 and the P-side electrode 11 to detect the temperature.

[0012]

According to the invention of claim 1, the first rectifier circuit is used.
Since the overcurrent detection thermistor is disposed on at least one of the second electrode and in the vicinity of the electrode, even when an overcurrent flows in any element of the semiconductor device,
Since the heat generated in the element can be detected by the thermistor for overcurrent detection, highly reliable overheat protection can be performed.

According to the second aspect of the present invention, since the thermistor for overcurrent detection is arranged at the end of the semiconductor device connecting side of at least one of the first and second electrodes, the heat generated in the element is generated. Can be instantly detected, and the thermistor can be placed on the electrodes with an adhesive, etc., so there is no need for an installation space or pattern on the insulating substrate, and the insulating substrate can be simplified, downsized, and cost reduced. Can be planned.

[Brief description of drawings]

FIG. 1 is an inverter circuit diagram to which a power module showing one embodiment of the present invention is applied.

FIG. 2 is an internal configuration diagram of the power module in FIG.

FIG. 3 is an inverter circuit diagram to which a conventional power module is applied.

[Explanation of reference numerals] 1 IGBT, 3 temperature sensor, 5 power module, 11 P side electrode, 12 N side electrode

Claims (2)

[Claims] 1. A semiconductor device, which is connected to first and second electrodes (P, N) to which substantially direct current power is applied and outputs multi-phase power, comprising at least the first and second electrodes. A semiconductor device comprising an overcurrent detecting thermistor disposed on one side or in the vicinity of the electrode. 2. The semiconductor device according to claim 1, wherein at least one of said first and second electrodes is provided with an overcurrent detection thermistor at an end of said electrode on the semiconductor device connection side.