JPH053234A - Method and apparatus for measuring temperature trip characteristics of semiconductor device - Google Patents

Abstract

PURPOSE:To improve conventional troublesome measurement of device characteristics such as the trip temperature and restoring temperature and the thermal resistance of the semiconductor device such as an intelligent power switch which are measured in such a manner that the device is heated by a heating plate and the operation of the device is observed on an oscilloscope or the like to measure the temperatures and the thermal resistance is measured by the other apparatus. CONSTITUTION:When an object device 4 has P-type FET's Q1, the device 4 is turned on by a control signal CS. Then the trip and restoration of the device 4 are detected by turning on FET's 11 and 12 and detecting the current and the voltage of a coil 17 and a comparator 10. On the other hand, before the start of measurement, immediately after trip and immediately after restoration, the signal CS and the FET's 11 and 12 are turned off, a relay RY1 and an FET 29 are turned on, measurement currents IM are applied to diodes 1 from a constant current source 2M and forward voltage drops VF of the diodes 1 are obtained through an A/D converter 33 and a CPU 34 to obtain a trip temperature and a restoring temperature. Currents IF are applied to the diodes 1 from a constant current power supply 2F and the forward voltage drops before, during and after the current application are inputted to the CPU 34 to obtain the thermal resistances of the diodes 1.

Description

Detailed Description of the Invention

[0001]

The present invention is turned on in response to a control signal,
When turned off, the upper and lower limit temperatures of the device are detected in this on state, and the temperature trip operation and the return operation are performed respectively. For example, the temperature trip characteristics of a semiconductor device such as an IPS (intelligent power switch), that is, the trip temperature and the return temperature. The present invention relates to a method and a device for measuring temperature and the like. Note that the temperature trip operation here is to input the control signal that should be turned on. When this semiconductor element has an excessive temperature rise, it detects the high temperature side limit value (trip temperature) of the guaranteed operating temperature range and outputs the output current. This is an operation of turning off, and the returning operation is an operation of detecting the temperature at which the semiconductor device, which has once performed the temperature trip operation, should return to the normal state and returning to the normal operation (operation of turning on the output current). Further, in the following drawings, the same reference numerals indicate the same or corresponding parts.

[0002]

2. Description of the Related Art Conventionally, there has been no apparatus for measuring the trip temperature and the return temperature of a semiconductor element (hereinafter also referred to as IPS for convenience) which performs the above-mentioned temperature trip operation and return operation. Therefore, to measure each temperature, I
Fix PS, etc. on the heater, operate IPS etc. steadily, raise (or lower) the temperature of hot plate while monitoring the temperature of hot plate of heater, and output voltage waveform or current waveform of IPS etc. The temperature trip operation and the return operation were confirmed while watching, and the trip temperature and the return temperature were measured by recording the temperature at that time. Although there is a device for measuring the thermal resistance Rth of a diode connected in parallel between the drain D and the source S of the output stage FET such as IPS (or between the collector C and the emitter E of the output stage transistor). However, there was no device to measure the trip temperature and return temperature at the same time as this thermal resistance.

[0003]

In order to measure the trip temperature and return temperature of the IPS or the like by the above-mentioned conventional method, one IPS or the like is attached to each heater and the temperature of the heater is slowly raised or lowered. Since it is necessary to monitor the output waveform of the IPS or the like, there is a problem that the measurement time of one element such as the IPS becomes enormous. Therefore, an object of the present invention is to provide a temperature trip characteristic measuring method and apparatus for a semiconductor element, which can easily measure the trip temperature and the recovery temperature of IPS or the like in a short time without using a heater or an oscilloscope, and at the same time measure the thermal resistance Rth. To do.

[0004]

In order to solve the above-mentioned problems, the method for measuring temperature trip characteristics according to claim 1 is turned on and off according to a control signal (CS, etc.), and in this on-state, A switching circuit (such as FET Q1) that trips when the temperature exceeds a predetermined trip temperature and switches to the off state, and returns to the on state when the temperature of the device itself falls below a predetermined return temperature, and a switching circuit of the circuit in parallel with the switching circuit. A diode (1 etc.) of the opposite polarity to the conduction polarity,
In a method of measuring a temperature trip characteristic of a semiconductor device (4 or the like) provided with, the trip circuit is tripped to the switching circuit via energization and heat generation to the switching circuit in an output state of the control signal for turning on the switching circuit. Then, the recovery is performed, and on the other hand, the forward voltage drop of the diode is calculated before the energization, immediately after the trip, and immediately after the recovery, and the trip temperature and the recovery temperature are calculated from the calculated forward voltage drop. And

The temperature trip characteristic measuring device of claim 2 is
It turns on and off according to a control signal (CS, etc.), and in this on state, when its own temperature exceeds a predetermined trip temperature, it trips and switches to the off state, and when its own temperature falls below a predetermined return temperature. A temperature trip characteristic of a semiconductor device (4, etc.) provided with a switching circuit (FET Q1, etc.) for returning to an ON state and a diode (1, etc.) having a polarity opposite to the conduction polarity of the switching circuit in parallel with the switching circuit is measured. In the device, in the output state of the control signal for turning on the switching circuit, means for energizing the switching circuit to generate heat (VCC applying power supply 16, FET 11, etc.) and the trip based on the heat generation are detected. Means (such as the coil 17) and a predetermined measurement current (such as IM) before the heat generation and immediately after the trip. ) The forward voltage drop by flowing (VF)
Means for obtaining the trip temperature from the difference between the two forward voltage drops (relay RY1, power supply 2M, FET2
9, AD converter 33, CPU 34, etc.), means for detecting the recovery of the switching circuit after the trip (FET 12, comparator 10, etc.), and the order of the diodes when the measured current flows immediately after the recovery. Means for obtaining the reset temperature from the difference between the voltage drop and the forward voltage drop before heat generation (relay RY1, power supply 2M, FET2
9, AD converter 33, CPU 34, etc.), and

The temperature trip characteristic measuring device according to claim 3 is
The temperature trip characteristic measuring device according to claim 2,
By passing a constant current (IF, etc.) to the diode,
A means for causing the diode to generate heat for a predetermined period (relay RY1, power supply 2F, FET 30, etc.), a means for measuring the power of this heat generation (A / D converter 33, CPU 34, etc.), and a predetermined period after the period. At the timing of, the measurement current is passed through the diode to measure its forward voltage drop,
A means for obtaining the thermal resistance of the diode from the difference in the forward voltage drop before and after the heat generation and the power of the heat generation (power supplies 2M, F
ET29, AD converter 33, CPU 34, etc.).

[0007]

In the state where the control signal for turning on the IPS is given, I
The PS is energized to generate heat, trip, and then recover. During this time, the forward voltage drop of the built-in diode is detected before energization, immediately after the trip, and immediately after the restoration, and the trip temperature,
Find the return temperature. If necessary, the temperature trip characteristic measuring device can also incorporate a function to measure the thermal resistance of the built-in diode.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 3 is an explanatory diagram of a general measurement principle of thermal resistance of a diode, and FIG. 3A shows a circuit of this principle.
FIGS. 9B and 9C show the waveforms of the current and voltage of the diode and the measurement timing, respectively. That is, the current shown in the time chart of FIG. 2B is applied to the diode 1 under measurement of FIG.
The forward voltage drop VF value of the diode 1 is supplied from the constant current power source 2 in the order of M, and the forward voltage drop VF of the diode 1 at the timing of VF0, VF1 and VF2 shown in the time chart of FIG. The measurement is performed via the measurement circuit 3. The thermal resistance Rth is represented by the following (formula 1) using the measured value of VF. Rth = {(VF1-VF2) / IF · VF0 · k} + Ta (Equation 1) where k: constant Ta: measurement room temperature.

Next, FIG. 4 shows a configuration example of a thermal resistance measuring circuit such as IPS. A semiconductor element (IPS or the like) that performs a temperature trip operation and a recovery operation is generally configured as the semiconductor element 4 (4P, 4N) shown in FIGS. 4A and 4B. The semiconductor elements 4P and 4N can turn on / off the FET (or transistor) Q1 at the output stage by giving a control signal CS. Here, the semiconductor element 4P receives an output current from its out terminal (output terminal), whereas the semiconductor element 4N flows in, and whether the output stage FET Q1 is a P channel or an N channel (in the case of a transistor, PNP or NPN). There is a difference. In either type, an inverse diode 1 is inserted in parallel between the drain and source of the FET Q1 in the output stage, and the thermal resistance of the diode 1 can be measured by the circuit of FIG. 4 just as in FIG.

FIG. 5 shows a circuit for measuring the thermal trip characteristics (trip temperature, recovery temperature) of the semiconductor element 4 (IPS, etc.), and FIG. 6 shows the timing of generation of voltage and current in each part of FIG. 5 and 6, the FET Q1 at the output stage of the semiconductor element 4 is a P-channel type semiconductor element 4P.
In case of N channel type semiconductor element 4N
But exactly the same. Next, FIG. 5 will be described with reference to FIG. The output of the element 4P is turned on by the control signal CS, and by turning on the FET 11, a current close to a short circuit is caused to flow through the element 4P through the constant current / constant voltage power source 16 (however, this current is limited by this power source 16). Element 4
Heat P. When the temperature of the element 4P reaches the upper limit (trip temperature) of the operating temperature, the output current Iout
Is turned off, and the change in current at that time is detected by the ferrite core coil 17 to detect the trip operation.

Next, the FET 11 is turned off and the FET 12 is turned on. Here, when the element temperature decreases and reaches the return temperature, the output current Iout starts flowing from the element 4P. At that time, the voltage drop across the series resistor 13 of the FET 12 is detected by the comparator 10 to detect the return operation. Output OFF (that is, control signal CS, FET11, FET12) before the trip operation and immediately after the trip operation and immediately after the recovery operation.
In the OFF state, the measuring current IM is passed from the constant current power source 2 to the element 4P, and the VF measuring circuit 3 measures the forward voltage drop VF of the diode 1 of the output stage FETQ1 of the semiconductor element 4P. These forward voltage drops VF1, VF3, VF4
The timing of the measurement is as shown in the time chart of FIG. As a result, the trip temperature Temp1
Is Temp1 = {(VF1-VF3) / k} + Ta-(Equation 2) where k is a constant, and the return temperature Temp2 is Temp2 = {(VF1-VF4) / k} + Ta-(Equation 3) ) Can be calculated as The semiconductor device 4N having an N-channel type output stage can be measured by the same method.

FIG. 1 shows a circuit configuration as an embodiment of the present invention. The semiconductor device under test (IPS, etc.) 4 may be either a P-channel type (type A) device 4P whose output stage FET is shown by a solid line or an N-channel type (type B) device 4N shown by a dotted line. In FIG. 1, similar to FIG. 5, FETs 11 and 12 for exclusive use of type A and a comparator 10 are provided, and FETs 11B, FET 12B and comparator 10B for exclusive use of type B are further added to correspond to each. For type A, turn relay RY1 ON, and for type B, turn RY2 ON.
By changing to N, the route for passing the currents IM and IF for measuring the temperature and the thermal resistance of the diode 1 in the semiconductor element 4 is changed. In this case, for the currents IM and IF, the constant current power supplies 2M and 2F are separately used, and as shown in FIGS. 3B and 6, the FET 29 and the FET 30 are turned on at the timings of flowing the respective currents IM and IF. . At the same time, the forward voltage drop VF of the diode 1 is input to the CPU 34 through the A / D converter 33 to obtain the thermal resistance Rth value, the trip temperature Temp1, and the reset temperature Temp.
2 calculation is performed.

FIG. 2 is a block diagram of the entire apparatus.
The CPU 34 performs overall control. Using the setting / display / operation unit 35, the start / stop command output and the logic timing are set, and the measurement result is displayed.
The measurement result is output to the printer 43 as needed. The interface 37 is a circuit for applying a timing signal to the semiconductor element 4 and a detection circuit for temperature trip operation and recovery operation, the contents of which are as shown in FIG.

When measuring only the thermal resistance Rth of the element 4 in the circuit of FIG. 1, the operation of FIG. 3 is performed. Note that the timings of the currents IM and IF flowing are FET 29 and F, respectively.
Controlled by ET30. When measuring the trip temperature and the return temperature, the operation shown in FIG. 5 is performed. However, the current I
The timing of the flow of M is controlled by the FET 29. When measuring the thermal resistance, trip temperature, and return temperature, the operation of FIG. 5 is performed after the operation of FIG. However, Figure 3
VF1 of the time chart of (C) and VF1 of the time chart of FIG. 6 are forward voltage drop VF values of the diode 1 at room temperature, and since the values are the same, VF1 of the time chart of FIG. 6 is not measured. That is, in order to shorten the measurement time, the value of VF1 in (Equation 1) to (Equation 3) is shared with the value of VF1 in the time chart of FIG. The measurement modes 1 to 3 above are set and input by the setting unit 35 in FIG. 2, and the measurement sequence is controlled by the CPU 34.

[0015]

According to the present invention, it is turned on / off according to the control signal CS, and in this on state, when its own temperature becomes equal to or higher than a predetermined trip temperature, it trips and is switched to the off state. FETQ as a switching circuit that returns to the ON state when the temperature drops below a predetermined reset temperature
1. In a device for measuring a temperature trip characteristic of a semiconductor element 4 including a diode 1 having a polarity opposite to a conduction polarity of the switching circuit in parallel with the switching circuit, the control signal CS for turning on the switching circuit Q1 In the output state, the switching circuit Q1 is caused to carry out the trip through the heat generated by energization to the switching circuit Q1, and then the recovery is carried out, while the forward voltage of the diode is supplied before the energization, immediately after the trip, and immediately after the recovery. Since the drop is obtained and the trip temperature and the return temperature are obtained from the obtained forward voltage drop, the measuring device can be added with the function of measuring the thermal resistance of the diode 1.
It is possible to easily measure the thermal resistance, the trip temperature, and the recovery temperature of the semiconductor element (IPS, etc.) 4 simultaneously or individually in a short time.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a main configuration of an apparatus as an embodiment of the present invention.

FIG. 2 is a block diagram showing the overall configuration of the device.

FIG. 3 is an explanatory diagram of the principle of measuring the thermal resistance of a diode.

FIG. 4 Principle circuit diagram of thermal resistance measurement of IPS etc.

FIG. 5 is a circuit diagram of a measurement principle based on the present invention of a temperature trip characteristic of IPS or the like.

FIG. 6 is a time chart of voltage and current of each part in FIG.

[Explanation of symbols]

1 diode 2 (2M, 2F) constant current power supply 3 VF measuring circuit 4 (4P, 4N) Semiconductor device under test (IPS, etc.) 9 Output current detection circuit (trip detection circuit) 10 comparator 10B comparator 11 FET 11B FET 12 FET 12B FET 16 VCC constant current constant voltage power supply 17 Ferrite core coil RY1 relay RY2 relay 29 FET 30 FET 33 A / D converter 34 CPU 35 Setting / display / operation unit 37 Interface CS control signal

Claims (3)

[Claims] Claims: 1. Turning on and off according to a control signal, and in this on state, when the temperature of itself exceeds a predetermined trip temperature, it trips and switches to the off state, and the temperature of itself falls below a predetermined return temperature. Then, in a method for measuring a temperature trip characteristic of a semiconductor device provided with a switching circuit which returns to an ON state, a diode having a polarity opposite to the conduction polarity of the circuit in parallel with the switching circuit, the switching circuit should be turned on. In the output state of the control signal, the switching circuit is caused to perform the trip through the heat generated by the energization of the switching circuit, and then the recovery is performed. On the other hand, before the energization, immediately after the trip, and immediately after the recovery, the diode is sequentially operated. The voltage drop is calculated, and the trip temperature and reset temperature are calculated from the calculated forward voltage drop. Temperature trip characteristic measuring method of a semiconductor device according to. 2. Turning on and off according to a control signal, and in this on state, when the temperature of itself becomes a predetermined trip temperature or higher, it trips and switches to an off state, and the temperature of itself becomes below a predetermined return temperature. In a device for measuring a temperature trip characteristic of a semiconductor device having a switching circuit that returns to an ON state, a diode having a polarity opposite to the conduction polarity of the switching circuit in parallel with the switching circuit, the switching circuit should be turned on. In the output state of the control signal, means for energizing this switching circuit to generate heat,
A means for detecting the trip based on the heat generation, and a forward measurement voltage drop are measured by flowing a predetermined measurement current through the diode before and immediately after the heat generation.
Means for obtaining the trip temperature from the difference between the two forward voltage drops, means for detecting the return of the switching circuit after the trip, forward voltage drop of the diode when the measured current flows immediately after the return, and the forward voltage drop of the diode. A device for measuring temperature trip characteristics of a semiconductor device, comprising: means for obtaining the return temperature from a difference from a forward voltage drop before heat generation. 3. The temperature trip characteristic measuring device according to claim 2, wherein a constant current is applied to the diode,
A means for causing the diode to generate heat for a predetermined period, a means for measuring the power of the heat generation, and a forward voltage drop of the diode for measuring the forward voltage drop by flowing the measurement current to the diode at a predetermined timing after the period. An apparatus for measuring temperature trip characteristics of a semiconductor device, comprising: means for obtaining the thermal resistance of the diode from the difference in forward voltage drop before and after heat generation and the power of the heat generation.