JPH11150853A - Overcurrent protective device, semiconductor switch device and intelligent power module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a current protective device, a semiconductor switch device and an intelligent power module, wherein the accuracy of an overcurrent protecting function of detecting a load current and the control of computing multiplication of product of current and time can be enhanced. SOLUTION: An overcurrent converting means 12 having a current-voltage conversion portion 12B which converts current-to-voltage load current information 12a within a specified dynamic range, a control means 32 which controls the computation of the product of current and time, and an overcurrent protective device 40 provided with a first-kind current protecting means 14 which determines any state of overcurrent and informs the occurrence of the state of overcurrent and a second-kind current protecting means 16 which determines the instantaneous allowable current are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device and, more particularly, to an overcurrent protection device for detecting a state of a load current generated by a load driving circuit for driving a load, a semiconductor switch device using the same, and a semiconductor device using the same. Related to intelligent power modules.

[0002]

2. Description of the Related Art FIG. 5 is a circuit diagram for explaining a conventional intelligent power module having an overcurrent protection function.

A conventional intelligent power module having this kind of overcurrent protection function is disclosed in Japanese Patent Application No. 8-149623 (Title of Invention: Intelligent power switch and switching device, application date: June 1996). 11 (Applicant: Yazaki Corporation) (see FIG. 5).

[0005] That is, the intelligent power switch A shown in FIG. 5 is a means for controlling the supply of current to the load 7. If the current flows for a short time, the semiconductor switch 1 may be damaged. The comparator 4 is provided with a first threshold value Th0 corresponding to the large current, the second threshold value Th1 lower than the first threshold value Th0 is stored in the data storage means 2, and the detected current value detected by the current detection means 5 is The semiconductor switch 1 is turned off when the current exceeds the first threshold Th0 or when the control unit 3 determines that the current equal to or higher than the second threshold Th1 has continuously flowed for the predetermined time t0 or more.
It had an overcurrent protection function for FF control.

By providing such an overcurrent protection function, the semiconductor switch 1 is unnecessarily turned on by an inrush current.
There is described an effect that the semiconductor switch 1 can be sufficiently protected without performing FF control.

[0006]

However, in such a conventional intelligent power switch A, the current detecting means 5 detects a current in a current range from a current value of zero to a first threshold value Th0. There was a technical problem that it was difficult to achieve high accuracy of the current value.

As a result, the accuracy of the threshold value judgment by the comparator 4 as to whether or not the detected current value detected by the current detecting means 5 has become equal to or more than the first threshold value Th0, or the second threshold value Th1
There has been a technical problem that it is difficult to improve the accuracy of determining the duration of whether or not the above current has continued to flow for a certain time t0 or more.

In other words, it is difficult to accurately control the semiconductor switch 1 to OFF with a high threshold value judgment accuracy or a high duration time judgment accuracy (that is, to improve the overcurrent protection function with high accuracy). There has been a technical problem that it is difficult to sufficiently protect the semiconductor switch 1 with high accuracy without unnecessarily turning off the semiconductor switch 1 with a current.

An object of the present invention is to solve such a conventional problem. In particular, in an overcurrent protection device for detecting a state of a load current generated by a load driving circuit for driving a load, An overcurrent detection unit that detects a load current generated by the load drive circuit and outputs load current information; and a current-to-voltage conversion of load current information generated by the overcurrent detection unit within a predetermined dynamic range. Overcurrent conversion means having a current-voltage conversion unit that outputs
The load drive circuit holds current-time product information, which is the relationship between the load current and the time during which the load current can be continuously generated, and controls the load current to continue for the load duration based on the current-time product information. Control means for performing current-time product control for the drive circuit; and determining whether the load current is within a steady allowable current range that the load drive circuit can output steadily. A first type overcurrent protection means for judging an overcurrent state of the supply state of the load current outside the steady allowable current range when a load current outside the range is detected, and outputting a warning signal indicating occurrence of the overcurrent state; The load drive circuit determines whether the load current is within the instantaneous allowable current range that can be output instantaneously, and when the load current is detected outside the instantaneous allowable current range, the load outside the instantaneous allowable current range is detected. Supply of current A second type overcurrent protection means for judging an overcurrent state to notify the occurrence of the overcurrent state and outputting a load current cutoff signal for prompting a cutoff of supply of a load current outside the instantaneous allowable current range; The load current generated by the load drive circuit can be detected with high accuracy and load current information can be generated based on the overcurrent protection device having the overcurrent protection device. The load drive circuit can perform high-precision current-time product control on the load current when a warning signal is generated, and perform high-precision current-time product control on the load current when the load current-voltage conversion information is received. It is an object of the present invention to control the load drive circuit so that the overcurrent protection function can be improved in accuracy.

An overcurrent protection device, a load drive circuit, and a load drive circuit are activated according to a gate input signal to control a load current, and a load current cutoff control is performed according to a load current cutoff signal. According to the semiconductor switch device having the gate control means executed for the drive circuit, the load current generated by the load drive circuit can be detected with high accuracy to generate the load current information. Current-time product control of the load drive circuit, and high-precision current-time product control of the load current when a warning signal is generated can be performed in the load drive circuit. As a result of being able to perform high-precision current-time product
It is an object to improve the overcurrent protection function with high accuracy.

Further, an overcurrent protection device, a load driving circuit, a boosting means for generating a boosted potential by boosting a predetermined power supply voltage, and outputting a boosted potential to the load driving circuit in accordance with a gate input signal to drive the load. A load drive circuit is generated by an intelligent power module having a gate control means for activating a circuit to control a load current and executing a load current cutoff control for the load drive circuit in response to a load current cutoff signal. Load current information can be generated by detecting load current with high accuracy, and high-precision current-time product control can be executed for the load drive circuit based on this current-time product information.
High-precision current-time product control for the load current when a warning signal is generated can be executed in the load drive circuit, and when load current-voltage conversion information is received, high-precision current-time product control for the load current is performed in the load drive circuit An object of the present invention is to make it possible to increase the accuracy of the overcurrent protection function as a result of being executable.

[0012]

According to the first aspect of the present invention, there is provided an overcurrent protection device for detecting a state of a load current generated by a load drive circuit for driving a load.
0, an overcurrent detection unit 12A that detects the load current 22a generated by the load drive circuit 22 and outputs the load current information 12a, and outputs the load current information 12a generated by the overcurrent detection unit 12A to a predetermined An overcurrent protection device 40 including an overcurrent conversion unit 12 having a current-voltage conversion unit 12B that performs current-voltage conversion within a dynamic range and outputs load current-voltage conversion information 12b.

According to the first aspect of the present invention, it is possible to generate the load current / voltage conversion information 12b by converting the load current information 12a into a current voltage within a predetermined dynamic range. The load current 22a generated by the load 22 can be detected with high accuracy to generate the load current information 12a.

In addition, there is an effect that the current / time product control with high accuracy can be executed in the load drive circuit 22 based on the current / time product information 32a detected with high accuracy.

Further, when the load current / voltage conversion information 12b detected with high accuracy is received, the load current 22a
Drive / time product control with high accuracy
As a result, there is an effect that the accuracy of the overcurrent protection function can be improved.

According to the second aspect of the present invention, a load current 22a generated by the load driving circuit 22 for driving the load 30 is provided.
In the overcurrent protection device that detects the state of the load current, the load drive circuit 22 holds current time product information 32a that is related to the load current 22a and the time during which the load current 22a can be continuously generated, A control means 32 for comparing the current 22a with the current-time product information 32a to obtain a load duration that is a time during which the load drive circuit 22 can continuously generate the load current 22a. The current protection device 40.

According to the second aspect of the present invention, it is possible to generate the load current / voltage conversion information 12b by performing a current / voltage conversion on the load current information 12a within a predetermined dynamic range. The load current 22a generated by the load 22 can be detected with high accuracy to generate the load current information 12a.

As a result, the control means 32 compares the current time product information 32a defined by the relationship between the continuable time and the load current 22a with the load current 22a detected with high accuracy, and the load drive circuit 22 There is an effect that the load duration time, which is the time during which the current 22a can be continuously generated, can be obtained with high accuracy.

Further, based on the load continuation time and current time product information 32a detected with high accuracy, the control means 3
2 is capable of executing high-precision current-time product control in the load drive circuit 22.

Further, when receiving the load duration information and the load current / voltage conversion information 12b detected with high accuracy as described above, the control means 32 performs a high-precision current / time product control on the load current 22a with a load driving circuit. As a result, the overcurrent protection function can be improved in accuracy.

According to a third aspect of the present invention, a load current 22a generated by the load driving circuit 22 to drive the load 30 is provided.
In the overcurrent protection device for detecting the state of the above, the current-time product based on the current-time product relationship represented by the product of the time during which the load drive circuit 22 can continuously generate the load current 22a and the load current 22a While holding the information 32a,
The load driving circuit 22 includes a control unit 32 that compares the load current 22a with the current-time product information 32a to determine a load duration time during which the load drive circuit 22 can continuously generate the load current 22a. Overcurrent protection device 40
It is.

According to the third aspect of the present invention, the load current information 12a can be subjected to current-voltage conversion within a predetermined dynamic range to generate the load current-voltage conversion information 12b. The load current 22a generated by the load 22 can be detected with high accuracy to generate the load current information 12a.

As a result, the control means 32 compares the current-time product information 32a defined by the product relationship between the continuable time and the load current 22a with the load current 22a detected with high accuracy, and the load driving circuit 22 There is an effect that the load duration time, which is the time during which the load current 22a can be continuously generated, can be obtained with high accuracy.

Further, based on the load continuation time and current time product information 32a detected with high accuracy in this way, the control means 3
2 is capable of executing high-precision current-time product control in the load drive circuit 22.

Further, when receiving the load duration information and the load current / voltage conversion information 12b detected with high accuracy as described above, the control means 32 performs high-precision current / time product control on the load current 22a with a load driving circuit. As a result, the overcurrent protection function can be improved in accuracy.

The invention described in claim 4 is the invention according to claims 1 to 3
In the overcurrent protection device 40 according to any one of the above,
The control unit 32 uses the load current / voltage conversion information 12b from the overcurrent conversion unit 12 as the load current 22a in the current / time product relationship, and calculates the load current 22a based on the current / time product information 32a. The load drive circuit 2 performs control to continue for the load duration time.
2. An overcurrent protection device 40 configured to execute current / time product control executed for
It is.

According to the invention described in claim 4, according to claim 1 of the present invention,
The same effects as the effects described in 1 to 3 are achieved.

[0028] The invention according to claim 5 is the invention according to claims 1 to 3.
In the overcurrent protection device 40 according to any one of the above,
The control unit 32 uses the load current / voltage conversion information 12b from the overcurrent conversion unit 12 as the load current 22a in the current / time product relationship, and calculates the load current 22a based on the current / time product information 32a. The load drive circuit 2 performs control to continue for the load duration time.
2 and the next smaller load current 2 based on the current-time product relationship after the end of the load duration.
The load drive circuit 22 controls the load drive circuit 22 to determine the load duration that is the continuation time of the load current 2a and the next smaller load current 22a and continue the load current 22a for the load duration.
The overcurrent protection device 40 is configured to execute current-time product control performed on the overcurrent protection device 40.

According to the invention described in claim 5, according to claim 1,
The same effects as the effects described in 1 to 3 are achieved.

The invention according to claim 6 is the invention according to claim 4 or 5
In the overcurrent protection device 40 described in the above, the control means 3
2. The current-time product control executed in step 2 controls the load current 22a according to the current-time product relationship in which the load current 22a changes stepwise to the next smaller load current 22a with respect to the load duration. The overcurrent protection device 40 is characterized by stepwise current-time product control.

According to the invention of claim 6, according to claim 4,
Or, in addition to the effect described in 5, the load current information 12a can be subjected to current-voltage conversion within a predetermined dynamic range to generate the load current-voltage conversion information 12b, so that the load drive circuit 22 generates a load. There is an effect that the load current information 12a can be generated by detecting the current 22a with high accuracy.

As a result, the control means 32 compares the current time product information 32a defined by the product relationship between the continuable time and the load current 22a with the load current 22a detected with high accuracy, and the load driving circuit 22 There is an effect that the load duration time, which is the time during which the load current 22a can be continuously generated, can be obtained with high accuracy.

Further, based on the load continuation time and current time product information 32a detected with high accuracy as described above, the control means 3
2 performs high-precision step-by-step current-time product control
2 can be executed.

Further, when receiving the load duration information and the load current / voltage conversion information 12b detected with high accuracy, the control means 32 performs a high-precision stepwise current / time product control on the load current 22a. As a result of being able to be executed by the drive circuit 22, there is an effect that the accuracy of the overcurrent protection function can be improved.

The invention described in claim 7 is the invention according to claims 1 to 6
In the overcurrent protection device 40 according to any one of the above,
The current-voltage converter 12B uses the voltage between the ground potential and the power supply potential of the control means 32 as the predetermined dynamic range, and converts the load current-voltage conversion information 12b generated by the overcurrent detector 12A to the ground potential. The current-time product information 3 by converting the current to voltage within the voltage between the power supply potentials
2a, wherein the overcurrent protection device 40 is configured to generate 2a.

According to the invention described in claim 7, according to claim 1 of the present invention,
In addition to the effects described in any one of (1) to (6), the load current information 12a is subjected to current-voltage conversion within the voltage (= dynamic range) between the ground potential and the power supply potential of the control means 32 to perform current-time product control. On the other hand, the overcurrent detection unit 12A can generate highly accurate load current / voltage conversion information 12b having optimal accuracy (that is, optimize the accuracy of the load current / voltage conversion information 12b).

Further, based on the current-time product information 32a detected by the current-voltage converter 12B at the optimum high accuracy, the current-time product control by the control means 32 can be executed at the optimum high accuracy. Play.

According to an eighth aspect of the present invention, in the overcurrent protection device 40 according to the seventh aspect, the control means 32 comprises:
It is configured to execute current-time product control using the load current / voltage conversion information 12b having the predetermined dynamic range corresponding to a voltage between its own ground potential and power supply potential. An overcurrent protection device 40.

According to the invention described in claim 8, according to claim 7,
In addition to the effects described in (1), the load current information 12a is subjected to current-to-voltage conversion within a voltage (= dynamic range) between the ground potential and the power supply potential of the control means 32, and the current / time product control has optimal accuracy. Highly accurate load current / voltage conversion information 1
2b (that is, load current / voltage conversion information 12
As a result, the load driving circuit 2 can be optimized.
2 detects the load current 22a generated by
2a can be generated with high precision that is optimal for current-time product control (that is, optimization of the accuracy of the load current information 12a).

Specifically, when the control means 32 takes in the load current information 12a as digital data therein, the control means 32 converts the load current / voltage conversion information 12b and the load current information 1a into digital data.
By optimizing the accuracy of 2a, the load current information 12a can be A / D-converted and converted into digital data within the voltage between the ground potential and the power supply potential.
The load current information 12a with high precision can be obtained with the / D conversion precision, and the current / time product control can be digitally processed with the optimum high precision using the load current information 12a optimized with high precision. (That is, the accuracy of current / time product control can be optimized).

As a result, the control means 32 compares the current time product information 32a defined by the product relationship between the continuable time and the load current 22a with the load current 22a detected with optimum high accuracy, and performs load driving. There is an effect that the load duration time, which is the time during which the circuit 22 can continuously generate the load current 22a, can be obtained with optimum high accuracy.

Further, based on the load duration time and the current time product information 32a detected with the optimum and high precision as described above, the control means 32 performs the stepwise current / time product control optimized with high precision by the load driving circuit. 22 is achieved.

Further, when receiving the load duration information and the load current / voltage conversion information 12b detected with the optimum and high precision as described above, the control means 32 causes the control means 32 to adjust the load current 22a with the highly accurate and optimized stepwise current. -As a result of being able to execute the time product control in the load drive circuit 22, it is possible to optimize the accuracy of the overcurrent protection function.

The ninth aspect of the present invention is the seventh aspect or the eighth aspect of the present invention.
In the overcurrent protection device 40 described in (1), there is provided a constant voltage generation unit 42 that generates a voltage between the ground potential and a power supply potential used as the predetermined dynamic range and supplies the power supply potential to the control unit 32. The overcurrent protection device 40 is characterized in that:

According to the ninth aspect of the present invention, a seventh aspect is provided.
Or in addition to the effect described in 8, the constant voltage generating means 42 is used to stabilize the voltage between the ground potential and the power supply potential with high accuracy against disturbances such as temperature changes, load fluctuations, and noise. Optimization of the accuracy of the load current / voltage conversion information 12b,
It is possible to optimize the accuracy of the load current information 12a, the accuracy of the current / time product control, and the accuracy of the overcurrent protection function.

According to a tenth aspect of the present invention, in the overcurrent protection device 40 according to the seventh or eighth aspect, a voltage between the ground potential and the power supply potential used as the predetermined dynamic range is generated, and A constant voltage generating unit 42 for supplying a power supply potential to the control unit 32 and the current / voltage conversion unit 12B;
Is configured to convert the load current information 12a into a current voltage within the voltage between the ground potential and the power supply potential, generate the load current / voltage conversion information 12b, and output the generated load current / voltage conversion information 12b to the control unit 32. Characteristic overcurrent protection device 40
It is.

According to the tenth aspect, the same effect as the seventh or eighth aspect can be obtained.

According to the eleventh aspect of the present invention, the load current generated by the load driving circuit 22 to drive the load 30 is
In the overcurrent protection device that detects the state of a, the load drive circuit 22 determines whether or not the load current 22a exists within a steady allowable current range that can be constantly output, and determines whether the load current 22a is out of the steady allowable current range. When the load current 22a is detected, the supply state of the load current 22a outside the steady allowable current range is determined to be an overcurrent state, and a warning signal 142a for notifying the occurrence of the overcurrent state is output. An overcurrent protection device 40 having a current protection means 14.

According to the eleventh aspect, the control means 32 directly outputs the warning signal 142 from the first type overcurrent protection means 14 without passing through the overcurrent conversion means 12.
a can be received.

As a result, the control means 32 provides the load driving circuit 22 with high-precision current / time product control that is optimal for the load current 22a when the warning signal 142a is generated by the first type overcurrent protection means 14. There is an effect that it can be executed quickly without the intervention of the overcurrent conversion means 12.

According to a twelfth aspect of the present invention, in the overcurrent protection device 40 according to the eleventh aspect, the first type overcurrent protection means 14 includes a predetermined warning reference potential 1.
42b is used as the steady-state current upper limit value which is the upper limit value of the steady allowable current range, and the warning reference potential 1
The overcurrent protection device 40 is configured to output the warning signal 142a when the load current 22a of 42b or more is detected.

According to the twelfth aspect of the present invention, in addition to the effect of the eleventh aspect, the control means 32 uses the warning reference potential 142b as the steady-state current upper limit value to control the first-class overcurrent protection means. 14 is a warning signal 142
By generating a, there is an effect that the high-precision current-time product control that is optimal for the generation of the load current 22a equal to or larger than the steady-state current upper limit value can be executed for the load drive circuit 22.

According to a thirteenth aspect of the present invention, in the overcurrent protection device 40 according to the eleventh or twelfth aspect of the present invention, the first
The seed overcurrent protection means 14 determines whether the load current / voltage conversion information 12b corresponding to the load current 22a exists within the steady allowable current range, and determines whether the load current voltage The overcurrent protection device 40 is configured to output the warning signal 142a when the conversion information 12b is detected.

According to the thirteenth aspect of the present invention, the same effect as that of the eleventh or twelfth aspect is obtained.

The fourteenth aspect of the present invention is the fourth aspect of the present invention.
In the overcurrent protection device 40 according to any one of 5, 6, 8, 11, 12, and 13, the control unit 32 includes:
An overcurrent protection device configured to execute the current-time product control on the load current at the time when the warning signal is generated, when the warning signal is received; It is.

According to the fourteenth aspect of the present invention, the same effect as any one of the fourth, fifth, sixth, eighth, eleventh, twelfth and thirteenth aspects can be obtained.

According to a fifteenth aspect of the present invention, the load current generated by the load drive circuit 22 to drive the load 30 is
In the overcurrent protection device that detects the state of a, the load drive circuit 22 determines whether or not the load current 22a exists within an instantaneous allowable current range that can be output instantaneously. When the load current 22a is detected, the supply state of the load current 22a outside the instantaneous allowable current range is judged as an overcurrent state to notify the occurrence of the overcurrent state, and the load outside the instantaneous allowable current range is notified. Current 22
a load current cutoff signal 162a for prompting the cutoff of the supply of
An overcurrent protection device 40 having a second type overcurrent protection means 16 that outputs the following.

According to the fifteenth aspect of the present invention, the provision of the second type overcurrent protection means 16 may cause an overcurrent state or a serious problem in the load drive circuit 22 even if the current flows instantaneously. Even if an excessively large load current 22a occurs in the load drive circuit 22, such an excessively large load current 22a can be cut off directly and instantaneously without the intervention of the control means 32. It has the effect of becoming.

As a result, there is an effect that an overcurrent protection function having an overcurrent immediate stop function can be realized.

According to a sixteenth aspect of the present invention, in the overcurrent protection device 40 of the fifteenth aspect, the second type overcurrent protection means 16 sets a predetermined load current cut-off reference potential 162b to the instantaneous allowable current range. The load current cutoff signal 162a is output when the load current 22a that is equal to or higher than the load current cutoff reference potential 162b is detected. Overcurrent protection device 40.

According to the sixteenth aspect of the invention, in addition to the effect of the fifteenth aspect, even if the current flows instantaneously, the load drive circuit 22 may cause an overcurrent state or a serious problem. The load current cut-off reference potential 162b is used as the instantaneous current upper limit value of the excessive load current 22a.
When the seed overcurrent protection means 16 generates the load current cutoff signal 162a, the load current
There is an effect that the load drive circuit 22 can execute the direct and instantaneous cutoff control in response to the occurrence of “a”.

The invention according to claim 17 is the overcurrent protection device 40 according to claim 15 or 16, wherein
The seed overcurrent protection unit 16 determines whether the load current / voltage conversion information 12b corresponding to the load current 22a exists within the instantaneous allowable current range, and determines whether the load current voltage The overcurrent protection device 40 is configured to output the load current cutoff signal 162a when the conversion information 12b is detected.

According to the seventeenth aspect of the invention, in addition to the effect of the fifteenth or sixteenth aspect, even if the current flows momentarily, an overcurrent state or a serious problem may be caused in the load drive circuit 22. Using the load current cut-off reference potential 162b as the instantaneous current upper limit value of a certain excessive load current 22a, the load current / voltage conversion information 12 detected with optimum high accuracy.
By determining whether or not b is within the instantaneous allowable current range, the load drive circuit 22 optimally performs the direct and instantaneous cutoff control for the generation of the load current 22a equal to or more than the instantaneous current upper limit. This has the effect of being able to be executed with high precision.

The invention according to claim 18 is directed to claim 4,
In the overcurrent protection device 40 according to any one of 5, 6, 8, 15, 16, and 17, the control unit 32 includes:
The overcurrent protection device 40 is configured to execute a cutoff control of the load current 22a for the load drive circuit 22 when the load current cutoff signal 162a is received.

According to the eighteenth aspect of the present invention, in addition to the effects of any one of the fourth, fifth, sixth, eighth, fifteenth, and seventeenth aspects, the control means 32 can provide a highly accurate control. There is an effect that the load drive circuit 22 can execute the cutoff control in conjunction with the cutoff control in conjunction with the optimized stepwise current / time product control.

Further, the load drive circuit 22 can execute the cutoff control in conjunction with the stepwise current / time product control that is optimized with high precision for the load current 22a, and as a result, the accuracy of the overcurrent protection function can be reduced. There is an effect that optimization can be achieved.

The invention according to claim 19 is the invention according to claims 6 and 1
The overcurrent protection device 40 according to any one of 4 or 19
The control means 32 performs the current-time product control on the load current 22a when receiving the load current-voltage conversion information 12b, and executes the warning signal 142a when receiving the warning signal 142a.
The current / time product control is performed on the load current 22a at the time of occurrence, and the cutoff control of the load current 22a is performed on the load drive circuit 22 when the load current cutoff signal 162a is received. Is configured as
An overcurrent protection device 40 characterized in that:

According to the nineteenth aspect of the present invention, in addition to the effect of any one of the sixth, fourteenth, and nineteenth aspects, the first type using the warning reference potential 142b as the steady-state current upper limit value. The generation of the warning signal 142a by the overcurrent protection means 14 enables the load drive circuit 22 to perform cutoff control in conjunction with high-precision current-time product control that is optimal for generation of a load current 22a that is equal to or higher than the steady-state current upper limit.
To be executed.

According to a twentieth aspect of the present invention, in the semiconductor switch device 50 using the overcurrent protection device 40 according to any one of the first to nineteenth aspects, the load drive circuit 22 and the gate input signal 20a are provided. Gate control that activates the load drive circuit 22 in response to the load current 22a and controls the load drive circuit 22 to cut off the load current 22a in response to the load current cutoff signal 162a. A semiconductor switch device 50 having means 20.

According to the twentieth aspect of the present invention, in addition to the effect of any one of the first to nineteenth aspects, the overcurrent protection device 40 is used to stabilize the overcurrent with high accuracy. Load current information 12a is subjected to current-voltage conversion within a voltage (= dynamic range) between the ground potential and the power supply potential of protection device 40, so that the accuracy of load current-voltage conversion information 12b can be optimized. There is an effect that the load current 22a generated by the circuit 22 is detected and the accuracy of the load current information 12a can be optimized.

Specifically, when the overcurrent protection device 40 takes in the load current information 12a as digital data into itself, the overcurrent protection device 40 depends on the optimization of the accuracy of the load current / voltage conversion information 12b and the load current information 12a. As a result, the load current information 12a can be converted into digital data by A / D conversion within the voltage between the ground potential and the power supply potential. As a result, highly accurate load current information 12a can be obtained with optimal A / D conversion accuracy. This makes it possible to optimize the accuracy of the above-described current / time product control using the load current information 12a optimized with high accuracy.

As a result of optimizing the accuracy of the current-time product control, the current-time product information 32a defined by the product relationship between the continuable time and the load current 22a and the load current detected with the optimum high precision Compared with the load driving circuit 22a, the load driving circuit 22 can obtain a load duration time, which is a time period during which the load current 22a can be continuously generated, with an optimum high accuracy.

Further, based on the load duration time and the current time product information 32a detected with the optimum high precision as described above, the gate control means 20 performs the stepwise current / time product control optimized with high precision by load driving. There is an effect that the circuit 22 can be executed.

Further, a warning reference potential 142
The overcurrent protection device 40 generates a warning signal 142a using b as the steady-state current upper limit value, and thereby performs a highly accurate current-time product control that is optimal for generation of the load current 22a that is equal to or greater than the steady-state current upper limit value. There is an effect that the gate control means 20 can be executed for the load drive circuit 22.

Further, even if the current flows instantaneously, the load driving circuit 22
Even when an excessive load current 22a that may cause an overcurrent state or a serious problem occurs in the load drive circuit 22, such an excessive load current 22a is directly and instantaneously supplied to the gate control means. 20 has an effect that it can be cut off. As a result, there is an effect that an overcurrent protection function having an overcurrent immediate stop function can be realized.

According to a twenty-first aspect of the present invention, in the semiconductor switch device 50 according to the twentieth aspect, the load drive circuit 22 is a power MOSFET 22, and the gate control means 20 responds to the gate input signal 20a. By controlling the potential of the gate of the power MOSFET 22 by the
The load current 22a flowing between the drains is controlled, and the load current 22a flowing between the source and the drain is cut off in response to the load current cutoff signal 162a. A semiconductor switch device 50.

According to the twenty-first aspect of the present invention, the voltage (= dynamic range) between the ground potential and the power supply potential of the overcurrent protection device 40 stabilized with high accuracy by using the overcurrent protection device 40. As a result, the load current information 12a is subjected to current-voltage conversion, and the accuracy of the load current-voltage conversion information 12b can be optimized. As a result, the load current 22a flowing between the source and the drain of the power MOSFET 22 is detected, and the load current 22a is detected. There is an effect that the accuracy of the information 12a can be optimized.

More specifically, when the overcurrent protection device 40 takes in the load current information 12a as digital data into itself, it depends on the optimization of the accuracy of the load current / voltage conversion information 12b and the load current information 12a. As a result, the load current information 12a can be converted into digital data by A / D conversion within the voltage between the ground potential and the power supply potential. As a result, highly accurate load current information 12a can be obtained with optimal A / D conversion accuracy. This makes it possible to optimize the accuracy of the above-described current / time product control using the load current information 12a optimized with high accuracy.

As a result of optimizing the accuracy of the current-time product control, the current-time product information 32a defined by the product relationship between the continuable time and the load current 22a and the load current detected with optimum high precision Power MOSFET compared to 22a
There is an effect that a load duration time, which is a time during which the load current 22a can be continuously generated between the source and the drain of the semiconductor device 22, can be obtained with optimum high accuracy.

On the basis of the load duration time and the current time product information 32a detected with the optimum high precision, the gate control means 20 performs the step current / time product control optimized with high precision by the power MOSFET 22. This has the effect that the program can be executed in a short time.

The warning reference potential 142
The overcurrent protection device 40 generates a warning signal 142a using b as the steady-state current upper limit value, and thereby performs a highly accurate current-time product control that is optimal for generation of the load current 22a that is equal to or greater than the steady-state current upper limit value. There is an effect that the gate control means 20 can be executed on the gate of the power MOSFET 22.

Even if the current flows instantaneously, the power MOSFE
An excessive load current 22a that may cause an overcurrent state or a serious problem in T22
2, the gate control means 20 can directly and instantaneously control the potential of the gate of the power MOSFET 22 to cut off such an excessive load current 22a. It has the effect of becoming As a result, there is an effect that an overcurrent protection function having an overcurrent immediate stop function can be realized.

According to a twenty-second aspect of the present invention, in the intelligent power module 10 using the overcurrent protection device 40 according to any one of the first to nineteenth aspects, the load drive circuit 22 and the predetermined power supply potential A boosting means 18 that boosts VB to generate a boosted potential 18a; and outputs the boosted potential 18a to the load drive circuit 22 in response to a gate input signal 20a to activate the load drive circuit 22 to generate the load current 22a. The intelligent power module 10 further includes a gate control unit 20 that controls the load driving circuit 22 in accordance with the load current cutoff signal 162a.

According to the twenty-second aspect, the same effect as the twentieth aspect can be obtained.

According to a twenty-third aspect of the present invention, in the intelligent power module 10 according to the twenty-second aspect, the load drive circuit 22 is a power MOSFET 22, and the gate control means 20 responds to the gate input signal 20a. By outputting the boosted potential 18a to the gate of the power MOSFET 22 to control the potential of the gate, the load current 22a flowing between the source and the drain of the power MOSFET 22 is controlled, and the load current is cut off. The intelligent power module 10 is configured to execute cutoff control of a load current 22a flowing between the source and the drain in response to a signal 162a.

According to the twenty-third aspect, the same effect as that of the twenty-first aspect is obtained.

[0087]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit diagram for explaining an embodiment of the overcurrent protection device 40 of the present invention.

As shown in FIG. 1, the overcurrent protection device 40 comprises a constant voltage generation means 42, an overcurrent conversion means 12, a first type overcurrent protection means 14, a second type overcurrent protection means 16, and a control means. 32 as a basic configuration.

In the present embodiment, it is desirable to use, as the load drive circuit 22, a power MOSFET 22 whose drain and source are connected between the power supply voltage VB and the ground potential and whose gate can be controlled by the gate control means 20.

The constant voltage generating means 42 generates a voltage between the ground potential and the power supply potential Vcc used as a predetermined dynamic range, and at the same time, controls the power supply potential Vcc to the control means 32.
And a function of supplying the current-to-voltage converter 12B. In the present embodiment, the power supply potential Vcc is set to the DC voltage +5 V (that is, +5 Vdc).

The constant voltage generating means 4 having such a function
2, the voltage between the ground potential and the power supply potential Vcc is changed by temperature change, load change,
Optimizing the accuracy of the load current / voltage conversion information 12b, optimizing the accuracy of the load current information 12a, and optimizing the accuracy of the current / time product control by stabilizing with high accuracy the disturbance such as noise. This has the effect that the accuracy of the overcurrent protection function can be optimized.

As shown in FIG. 1, the overcurrent converter 12 has an overcurrent detector 12A and a current / voltage converter 12B as basic components.

The overcurrent converting means 12 has a power supply connected between the ground potential and the power supply potential Vcc, an output connected to the base of the transistor 122, and an input terminal connected to the load terminal through the resistance element 125 to detect the load current. An operational amplifier 121 having a (+) input terminal connected to one end of the resistance element 124 and the other end of the load current detection resistance element 124 via the resistance element 123, and a collector connected to the load current detection resistance element via the resistance element 123. An npn transistor 122 whose base is connected to the output of the operational amplifier 121 and whose emitter is connected to the resistor 126,
It is desirable to realize by the resistance element 126 connected between the emitter of the transistor 122 and the ground potential.

Here, one end of the load current detecting resistance element 124 is connected to the drain / source of the power MOSFET 22 and the other end is connected to the load current 22a supply terminal of the load 30.

The load 30 is a load current detecting resistance element 1
24, the power MOSFET 22 is connected between the drain / source and the ground potential.

The operational amplifier 121 having such a configuration
And the value of the current flowing through the resistance element 123 and the resistance element 126 depending on the circuit configuration using the npn transistor 122.
Can be equalized.

In the power MOSFET 22, the drain / source is connected to one end of the load 30, the source / drain is connected to the other end of the load 30, and the gate is connected to gate control means 20, which will be described later.

The overcurrent detecting section 12A has a power MOSFE
T22 (specifically, a power MOSFET described later) detects a load current 22a and generates load current information 12a.
Is characterized in that it has a function of outputting

The current-to-voltage converter 12B includes the overcurrent detector 1
It is characterized in that it has a function of converting the load current information 12a generated by the 2A into a current voltage within a predetermined dynamic range and outputting the load current / voltage conversion information 12b.

The current-to-voltage converter 12 B
2 using the voltage between the ground potential and the power supply potential Vcc as a predetermined dynamic range, and converting the load current / voltage conversion information 12b generated by the overcurrent detector 12A into the ground potential and the power supply potential Vcc.
Current-voltage conversion within the voltage between
Is generated.

The specific current-voltage converter 12B has a power supply connected between the ground potential and the power supply potential Vcc, an output connected to the control means 32, and an (-) input terminal connected to the output via the feedback resistance element 129. It is preferable to realize the operational amplifier 128 having the (+) input terminal connected to the resistance element 120 and the resistance element 127 connected between the (−) input terminal of the operational amplifier 128 and the ground potential.

The current-voltage converter 1 having such a function
2B, the load current information 12a is stored in a voltage between the ground potential and the power supply potential Vcc (that is, +5
The overcurrent detection unit 12A generates the high-precision load current-voltage conversion information 12b having the optimum accuracy for the current-time product control by performing the current-voltage conversion within Vdc = dynamic range (that is, the load current). Optimization of the voltage conversion information 12b).

Further, based on the current-time product information 32a detected by the current-voltage converter 12B with the optimum accuracy, the current-time product control in the control means 32 can be executed with the optimum accuracy. Play.

As described above, by providing the overcurrent conversion means 12 having such a function, the load current information 12a is converted into a current voltage within a predetermined dynamic range to generate the load current voltage conversion information 12b. As a result, the load current 22a generated by the power MOSFET 22 can be detected with high accuracy to generate the load current information 12a.

Further, there is an effect that the current / time product control with high accuracy can be executed for the power MOSFET 22 based on the current / time product information 32a detected with high accuracy.

Further, when the load current / voltage conversion information 12b detected with high accuracy is received, the load current 22a
Power-MOSFE for current / time product control with high accuracy
As a result of being able to be executed at T22, there is an effect that the accuracy of the overcurrent protection function can be improved.

The first type overcurrent protection means 14 has a power MO
It is determined whether or not the load current 22a exists within the steady allowable current range in which the SFET 22 can constantly output, and when the load current 22a is detected outside the steady allowable current range, the load current outside the steady allowable current range is detected. It is characterized in that it has a function of judging an overcurrent state of the supply state of 22a and outputting a warning signal 142a indicating occurrence of the overcurrent state.

The first type overcurrent protection means 14 uses the predetermined warning reference potential 142b as the upper limit of the steady current, which is the upper limit of the steady allowable current range, and detects the load current 22a equal to or higher than the warning reference potential 142b. In this case, the warning signal 142a is output.

Accordingly, the control means 32 uses the warning reference potential 142b as the steady-state current upper limit value, and the first type overcurrent protection means 14 uses the warning signal 142a.
Is generated, it is possible to execute a highly accurate current-time product control for the power MOSFET 22 that is optimal for the generation of the load current 22a equal to or larger than the steady-state current upper limit.

Further, the first type overcurrent protection means 14 determines whether or not the load current / voltage conversion information 12b corresponding to the load current 22a exists within the steady allowable current range. It is configured to output a warning signal 142a when the voltage conversion information 12b is detected.

Here, the steady allowable current range means a current range that is smaller than a current at which the load drive circuit 22 may be damaged if the current continues for a predetermined time or more.

Such a first type overcurrent protection means 14
Specifically, it is desirable to realize by the comparator 142 in which a power supply is connected between the ground potential and the power supply potential Vcc, and the output is pulled up to the power supply potential Vcc via the resistance element 143. The output of the comparator 142 is connected to the control means 32 described later in a state where the output is pulled up to the power supply potential Vcc via the resistance element 143.

The first type overcurrent protection means 14 uses the warning reference potential 142b as the upper limit of the steady current which is the upper limit of the steady allowable current range, and detects the load current 22a which is equal to or higher than the warning reference potential 142b. It is configured to output a warning signal 142a.

Specifically, it is desirable to use a configuration in which the warning reference potential 142b is input to the (-) terminal as the threshold value of the comparator 142, and the load current information 12a is input to the (+) terminal.

The comparator 142 calculates the load current information 12
a becomes equal to or higher than the warning reference potential 142b, a warning signal 14 indicating occurrence of an overcurrent state.
2a has an overcurrent protection function.

As described above, by providing the first type overcurrent protection means 14 having such a function, the control means 32 can directly control the first type overcurrent protection means without passing through the overcurrent conversion means 12. Warning signal 1 from current protection means 14
42a can be received.

As a result, the control means 32 performs optimal and accurate current-time product control on the load current 22a when the warning signal 142a is generated by the first type overcurrent protection means 14 with respect to the power MOSFET 22. Conversion means 12
This makes it possible to execute the program promptly without any intervention.

The second type overcurrent protection means 16 is provided with a power MO
It is determined whether the load current 22a exists within the instantaneous allowable current range in which the SFET 22 can output instantaneously. When the load current 22a is detected outside the instantaneous allowable current range, the load current outside the instantaneous allowable current range is determined. The function of outputting the load current cutoff signal 162a for prompting the cutoff of the supply of the load current 22a outside the instantaneous allowable current range at the same time as notifying the occurrence of the overcurrent state by judging the overcurrent state of the supply state of the 22a. There is a feature.

Here, the instantaneous allowable current range means a current range smaller than a large current that may damage the load drive circuit 22 when the current flows even in a short time.

Such a type II overcurrent protection means 16
Specifically, it is desirable to realize by a comparator 162 in which a power supply is connected between the ground potential and the power supply potential VB, and the output is pulled up to the power supply potential VB via the resistance element 163. The output of the comparator 162 is connected to the gate control means 20 described later in a state where the output is pulled up to the power supply potential VB via the resistance element 163.

The second type overcurrent protection means 16 uses the predetermined load current cut-off reference potential 162b as the upper limit of the instantaneous current which is the upper limit of the instantaneous allowable current range, and uses the load current 22a which is equal to or higher than the load current cut-off reference potential 162b.
Is configured to output a load current cut-off signal 162a when is detected.

Specifically, it is desirable to use a configuration in which the load current cut-off reference potential 162b is input to the (-) terminal as the threshold value of the comparator 162, and the load current information 12a is input to the (+) terminal.

The comparator 162 calculates the load current information 12
It has an overcurrent protection function of outputting a load current cutoff signal 162a for controlling the power MOSFET 22 to be turned off when a becomes equal to or higher than the load current cutoff reference potential 162b.

According to this, even if it flows instantaneously, the power MO
The second type overcurrent protection means 16 uses the load current cutoff reference potential 162b as the instantaneous current upper limit value of the overload current 22a that may cause an overcurrent state or a serious problem in the SFET 22, and the second type overcurrent protection means 16 outputs the load current cutoff signal 162a.
Is generated, there is an effect that the power MOSFET 22 can execute the direct and instantaneous cutoff control (that is, the OFF control) for the generation of the load current 22a equal to or more than the instantaneous current upper limit value.

Further, the second type overcurrent protection means 16 determines whether or not the load current / voltage conversion information 12b corresponding to the load current 22a is within the instantaneous allowable current range. It is configured to output a load current cutoff signal 162a when the voltage conversion information 12b is detected.

As described above, the provision of the second type overcurrent protection means 16 having such a function may cause an overcurrent state or serious trouble in the power MOSFET 22 even if it flows instantaneously. Even when such an overload current 22a occurs in the power MOSFET 22, such an effect can be obtained that the overload current 22a can be cut off directly and instantaneously without the intervention of the control means 32. Play.

As a result, there is an effect that an overcurrent protection function having an overcurrent immediate stop function can be realized.

The control means 32 uses the load current / voltage conversion information 12b from the overcurrent conversion means 12 as the load current 22a in the current time product relation, and uses the load current 22a as the load duration based on the current time product information 32a. At the same time as performing the continuous control on the power MOSFET 22, the next smaller load current 22a and the next smaller load current 22a are determined based on the current-time product relationship after the end of the load duration.
The load duration, which is the possible duration of the load current,
2a is controlled by the power MOSF
It is characterized in that it has a function of executing current / time product control executed on the ET 22.

The control means 32 uses the load current / voltage conversion information 12b having a predetermined dynamic range corresponding to the voltage between the ground potential and the power supply potential Vcc to control the current / current.
It has a function to execute time product control.

The specific control means 32 is mainly composed of a CPU, a RAM for holding calculation results and the like, a ROM for recording programs and the like, a peripheral interface for controlling transmission and reception of information with the outside, and the like. It is desirable to use a known microprocessor.

In the present embodiment, the control means 32 is provided inside the overcurrent protection device 40. However, the present invention is not limited to this. The control means 32 may be provided outside the overcurrent protection device 40. . When provided outside the overcurrent protection device 40, a microcomputer provided outside can execute the control function of the control means 32.

FIG. 2 is a current-time product characteristic diagram for explaining the stepwise current-time product control executed by the control means 32 of FIG.

As shown in FIG. 2, the current-time product control executed by the control means 32 is a current-time product relationship in which the load current 22a changes stepwise to the next smaller load current 22a with respect to the load duration. Is a stepwise current / time product control for controlling the load current 22a in accordance with

As shown in FIG. 2, a large load current 22a
The shorter the duration, the shorter the power MOS per unit time
It is desirable that the power output from the FET 22 does not exceed a certain value.

When the first type overcurrent protection means 14 is provided, the control means 32 outputs a warning signal 142a.
Is received, the current-time product control is performed on the load current 22a when the warning signal 142a is generated.

When the second type overcurrent protection means 16 is provided, the control means 32 controls the load current cutoff signal 162
a, the control means 32 is configured to execute the cutoff control (OFF control) of the load current 22a for the power MOSFET 22 when receiving the power MOSFET 22. Accordingly, the control means 32 can optimize the stepped current with high accuracy. An effect is obtained that the power MOSFET 22 can execute the cutoff control that is linked to the cutoff control that is linked to the time product control.

Further, the power MOSFET 22 can execute the cutoff control linked to the stepwise current / time product control, which is optimized with high accuracy, for the load current 22a, thereby optimizing the accuracy of the overcurrent protection function. It is possible to achieve the effect of being able to achieve.

The control means 32 executes current / time product control on the load current 22a when receiving the load current / voltage conversion information 12b, and when receiving the warning signal 142a, executes the current / time product control. The current-time product control is performed on the load current 22a, and when the load current cutoff signal 162a is received, the power MOSFE
It may be configured to execute the cutoff control of the load current 22a for T22. Accordingly, the first type overcurrent protection means 14 generates the warning signal 142a using the warning reference potential 142b as the steady-state current upper limit, and the load current 2 equal to or larger than the steady-state current upper limit.
There is an effect that the power MOSFET 22 can execute the cutoff control in conjunction with the high-precision current-time product control that is optimal for the occurrence of 2a.

As described above, by providing the control means 32 having such a function, the load current information 1
2a is subjected to current-to-voltage conversion within a voltage (= dynamic range) between the ground potential and the power supply potential Vcc of the control means 32, and the highly accurate load current-to-voltage conversion information 12b having optimum accuracy for current-time product control is obtained. As a result, the load current 22a generated by the power MOSFET 22 can be generated (that is, optimization of the accuracy of the load current / voltage conversion information 12b).
And the load current information 12a can be generated with high precision that is optimal for current-time product control (that is, the accuracy of the load current information 12a can be optimized).

Specifically, when the control means 32 takes in the load current information 12a as digital data therein, the control means 32 converts the load current / voltage conversion information 12b and the load current information 1a into digital data.
By optimizing the accuracy of 2a, the load current information 12a can be A / D converted and converted into digital data within a voltage between the ground potential and the power supply potential Vcc, resulting in an optimum A / D conversion accuracy. Thus, the load current information 12a can be obtained with high accuracy, and the current / time product control can be digitally processed with the optimum high accuracy by using the load current information 12a optimized with high accuracy ( That is, the current
This makes it possible to optimize the accuracy of the time product control).

As a result, the control means 32 compares the current-time product information 32a defined by the product relation between the continuable time and the load current 22a with the load current 22a detected with optimum high precision, and compares the power MOSFET 22 with the power MOSFET 22. Has an effect that a load duration time, which is a time during which the load current 22a can be continuously generated, can be obtained with optimum high accuracy.

Further, based on the load duration time and the current time product information 32a detected with the optimum high precision as described above, the control means 32 controls the power MOSFET 22 to perform the step current / time product control optimized with high precision. It has the effect of being able to execute.

Further, when receiving the load duration and load current-voltage conversion information 12b detected with the optimum and high precision as described above, the control means 32 controls the load current 22a with the highly precise and optimized step-by-step current.・ Power MO for time product control
As a result of being able to be performed on the SFET 22, there is an effect that the accuracy of the overcurrent protection function can be optimized.

Next, an embodiment of the semiconductor switch device 50 will be described with reference to the drawings.

FIG. 3 is a circuit diagram for explaining one embodiment of a semiconductor switch device 50 using the overcurrent protection device 40 of FIG. The same parts as those already described in the embodiment of the overcurrent protection device 40 are denoted by the same reference numerals, and redundant description will be omitted.

As shown in FIG. 3, the semiconductor switch device 50 has an overcurrent protection device 40, a load drive circuit 22, and a gate control means 20 as a basic configuration.

In the present embodiment, it is desirable to use, as the load drive circuit 22, a power MOSFET 22 having a drain and a source connected between the power supply voltage VB and the ground potential and a gate that can be controlled by the gate control means 20.

The gate control means 20 controls the gate input signal 2
0a to control the load current 22a by activating the power MOSFET 22 and at the same time,
2a, the cutoff control of the load current 22a is performed by the power MOS.
It is characterized in that it has a function to execute for the FET 22.

The gate control means 20 controls the load current 22a flowing between the source and the drain of the power MOSFET 22 by controlling the potential of the gate of the power MOSFET 22 according to the gate input signal 20a. The source according to the cutoff signal 162a
It is configured to execute cutoff control of the load current 22a flowing between the drains.

As described above, by providing the gate control means 20 having such a function, the ground potential-power supply of the overcurrent protection device 40 stabilized with high accuracy by using the overcurrent protection device 40 is provided. The load current information 12a is subjected to current-voltage conversion within the voltage (= dynamic range) between the potentials Vcc, and the accuracy of the load current-voltage conversion information 12b can be optimized.
There is an effect that the accuracy of the load current information 12a can be optimized by detecting the load current 22a flowing between the drains.

Specifically, when the overcurrent protection device 40 takes in the load current information 12a as its own digital data, the overcurrent protection device 40 depends on the optimization of the accuracy of the load current / voltage conversion information 12b and the load current information 12a. A / D load current information 12a within the voltage between ground potential and power supply potential Vcc.
As a result of conversion into digital data, high-precision load current information 12 with optimal A / D conversion accuracy can be obtained.
a can be obtained, and there is an effect that the accuracy of the current / time product control can be optimized using the load current information 12a optimized with high accuracy.

As a result of optimizing the accuracy of the current-time product control, the current-time product information 32a defined by the product relationship between the continuable time and the load current 22a and the load current detected with optimum high precision Power MOSFET compared to 22a
There is an effect that a load duration time, which is a time during which the load current 22a can be continuously generated between the source and the drain of the semiconductor device 22, can be obtained with optimum high accuracy.

Further, based on the load duration time and the current time product information 32a detected with the optimum high precision, the gate control means 20 performs the step current / time product control optimized with high precision by the power MOSFET 22. This has the effect that the program can be executed in a short time.

The warning reference potential 142
The overcurrent protection device 40 generates a warning signal 142a using b as the steady-state current upper limit value, and thereby performs a highly accurate current-time product control that is optimal for generation of the load current 22a that is equal to or greater than the steady-state current upper limit value. There is an effect that the gate control means 20 can be executed on the gate of the power MOSFET 22.

In addition, even if it flows instantaneously, the power MOSFE
An excessive load current 22a that may cause an overcurrent state or a serious problem in T22
2, the gate control means 20 can directly and instantaneously control the potential of the gate of the power MOSFET 22 to cut off such an excessive load current 22a. It has the effect of becoming As a result, there is an effect that an overcurrent protection function having an overcurrent immediate stop function can be realized.

Next, an embodiment of the intelligent power module 10 will be described with reference to the drawings.

FIG. 4 is a circuit diagram for explaining an embodiment of the intelligent power module 10 using the overcurrent protection device 40 of FIG. The same parts as those already described in the embodiment of the overcurrent protection device 40 are denoted by the same reference numerals, and redundant description will be omitted.

The Intelligent Power Module 10
As shown in FIG. 4, has a basic configuration including an overcurrent protection device 40, a load driving circuit 22, a booster 18, and a gate controller 20. In the present embodiment, the load driving circuit 2
As 2, it is desirable to use a power MOSFET 22 whose drain and source are connected between the power supply voltage VB and the ground potential and whose gate can be controlled by the gate control means 20.

The boosting means 18 has a function of boosting a predetermined power supply potential VB to generate a boosted potential 18a.

The gate control means 20 controls the gate input signal 2
0a, the boosted potential 18a is applied to the power MOSFET 22.
And activates the power MOSFET 22 to control the load current 22a.
Control of the load current 22a according to the power MOSFET
It has a function to be executed for T22.

The gate control means 20 outputs a boosted potential 18a to the gate of the power MOSFET 22 in response to the boosted gate input signal 20a to control the potential of the gate, thereby flowing between the source and the drain of the power MOSFET 22. At the same time that the load current 22a is controlled, the cutoff control of the load current 22a flowing between the source and the drain is executed according to the load current cutoff signal 162a.

As described above, according to the intelligent power module 10 of the present embodiment, the ground potential-power supply potential Vcc of the overcurrent protection device 40 stabilized with high accuracy by using the overcurrent protection device 40. Of the load current information 12a within the voltage (= dynamic range), and the accuracy of the load current / voltage conversion information 12b can be optimized. As a result, the load current 22a flowing between the source and drain of the power MOSFET 22 can be optimized. And it is possible to optimize the accuracy of the load current information 12a described above.

Specifically, when the overcurrent protection device 40 takes in the load current information 12a as digital data into itself, the overcurrent protection device 40 depends on the optimization of the accuracy of the load current / voltage conversion information 12b and the load current information 12a. A / D load current information 12a within the voltage between ground potential and power supply potential Vcc.
As a result of conversion into digital data, high-precision load current information 12 with optimal A / D conversion accuracy can be obtained.
a can be obtained, and there is an effect that the accuracy of the current / time product control can be optimized using the load current information 12a optimized with high accuracy.

As a result of optimizing the accuracy of the current-time product control, the current-time product information 32a defined by the product relationship between the continuable time and the load current 22a and the load current detected with optimum high precision Power MOSFET compared to 22a
There is an effect that a load duration time, which is a time during which the load current 22a can be continuously generated between the source and the drain of the semiconductor device 22, can be obtained with optimum high accuracy.

Further, based on the load duration time and the current time product information 32a detected with the optimum high precision as described above, the gate control means 20 performs the step current / time product control optimized with high precision by the power MOSFET 22. This has the effect that the program can be executed in a short time.

Further, the warning reference potential 142
The overcurrent protection device 40 generates a warning signal 142a using b as the steady-state current upper limit value, and thereby performs a highly accurate current-time product control that is optimal for generation of the load current 22a that is equal to or greater than the steady-state current upper limit value. There is an effect that the gate control means 20 can be executed on the gate of the power MOSFET 22.

In addition, even if the current flows instantaneously, the power MOSFE
An excessive load current 22a that may cause an overcurrent state or a serious problem in T22
2, the gate control means 20 can directly and instantaneously control the potential of the gate of the power MOSFET 22 to cut off such an excessive load current 22a. It has the effect of becoming As a result, there is an effect that an overcurrent protection function having an overcurrent immediate stop function can be realized.

[0169]

According to the first aspect of the present invention, it is possible to generate load current / voltage conversion information by converting load current information into current / voltage within a predetermined dynamic range. Has the effect of enabling the load current generated by the device to be detected with high accuracy and generating the load current information.

In addition, the present invention has an effect that high-precision current-time product control can be executed in the load drive circuit based on the current-time product information detected with high accuracy.

Further, upon receiving the load current / voltage conversion information detected with high accuracy as described above, the load drive circuit can execute the current / time product control with high accuracy on the load current. This brings about an effect that it is possible to improve the precision of the image.

According to the second aspect of the present invention, load current information can be converted into current by converting load current information within a predetermined dynamic range to generate load current / voltage conversion information. This makes it possible to detect load current to be generated with high accuracy and generate load current information.

As a result, the control means compares the current time product information defined by the relationship between the continuable time and the load current with the load current detected with high accuracy, and the load drive circuit continuously outputs the load current. There is an effect that the load continuation time, which is the time that can be generated, can be obtained with high accuracy.

Further, there is an effect that the control means can execute a high-precision current-time product control on the load drive circuit based on the load duration and the current-time product information detected with high accuracy. .

Further, upon receiving the load duration and load current-voltage conversion information detected with high accuracy in this way, the control means can execute a high-precision current-time product control on the load current to the load drive circuit. As a result, there is an effect that the accuracy of the overcurrent protection function can be improved.

According to the third aspect of the present invention, load current information can be converted into current by converting load current information within a predetermined dynamic range to generate load current voltage conversion information. This makes it possible to detect load current to be generated with high accuracy and generate load current information.

As a result, the control means compares the current-time product information defined by the product relationship between the continuable time and the load current with the load current detected with high accuracy, and the load driving circuit continuously outputs the load current. This is advantageous in that the load continuation time, which is the time that can be generated in a short time, can be obtained with high accuracy.

In addition, there is an effect that the control means can execute the current / time product control with high accuracy to the load drive circuit based on the load duration and the current / time product information detected with high accuracy. .

Further, when receiving the load duration and load current-voltage conversion information detected with high accuracy in this way, the control means can execute high-precision current-time product control on the load current to the load drive circuit. As a result, there is an effect that the accuracy of the overcurrent protection function can be improved.

According to the invention set forth in claim 4, according to claim 1,
The same effects as the effects described in 1 to 3 are achieved.

According to the invention set forth in claim 5, according to claim 1,
The same effects as the effects described in 1 to 3 are achieved.

According to the invention described in claim 6, according to claim 4,
Or, in addition to the effect described in 5, the load current information can be generated by converting the load current information into a current voltage within a predetermined dynamic range, so that the load current generated by the load drive circuit can be increased. This has the effect that load current information can be generated by detecting with accuracy.

As a result, the control means compares the current-time product information defined by the product relationship between the continuable time and the load current with the load current detected with high accuracy, and the load drive circuit continuously outputs the load current. This is advantageous in that the load continuation time, which is the time that can be generated in a short time, can be obtained with high accuracy.

Further, based on the load continuation time and current time product information detected with high accuracy in this way, the control means can execute high-precision stepwise current / time product control on the load drive circuit. To play.

Further, upon receiving the load duration and load current / voltage conversion information detected with high accuracy as described above, the control means performs high-precision stepwise current / time product control on the load current to the load drive circuit. As a result, there is an effect that the accuracy of the overcurrent protection function can be improved.

According to the invention of claim 7, according to claim 1,
In addition to the effects described in any one of (1) to (6) above, the load current information is converted from current to voltage within the voltage (= dynamic range) between the ground potential and the power supply potential of the control means to control current / time product control. The overcurrent detection unit can generate highly accurate load current / voltage conversion information having optimal accuracy (that is, optimize the accuracy of the load current / voltage conversion information).

Also, there is an effect that the current-time product control in the control means can be executed with optimum high accuracy based on the current-time product information detected by the current-voltage conversion unit with optimum high accuracy.

According to the invention of claim 8, according to claim 7,
In addition to the effects described in (1), high-precision conversion of load current information within the voltage (= dynamic range) between the ground potential and the power supply potential of the control means, which has an optimum precision for current-time product control As a result, it is possible to generate the load current-voltage conversion information (that is, optimize the accuracy of the load current-voltage conversion information). This produces an effect that it is possible to generate with high precision that is optimal for product control (that is, to optimize the accuracy of load current information).

Specifically, when the control means takes in the load current information as digital data into itself, it depends on the optimization of the accuracy of the load current / voltage conversion information and the load current information to determine whether or not the load potential information between the own ground potential and the power supply potential. As a result, the load current information can be converted into digital data by A / D conversion within the range of the voltage, so that highly accurate load current information can be obtained with optimal A / D conversion accuracy. The current-time product control can be digitally processed with optimal high precision using the load current information optimized in (2).
This makes it possible to optimize the accuracy of the current / time product control).

As a result, the control means compares the current-time product information defined by the product relationship between the continuable time and the load current with the load current detected with optimum precision, and the load drive circuit This is advantageous in that a load duration time, which is a time in which the load can be continuously generated, can be obtained with optimum high accuracy.

Further, based on the load duration time and current time product information detected with the optimum high precision as described above, the control means executes the step current / time product control which is optimized with high precision to the load driving circuit. It has the effect of being able to do so.

Further, upon receiving the load duration and load current / voltage conversion information detected with the optimum and high precision as described above, the control means controls the highly accurate and optimized current / time product for the load current. As a result of being able to execute the control in the load drive circuit, it is possible to optimize the accuracy of the overcurrent protection function.

According to the invention of claim 9, according to claim 7,
Or in addition to the effect of item 8, by using a constant voltage generating means to stabilize the voltage between the ground potential and the power supply potential with high accuracy against disturbances such as temperature changes, load fluctuations, and noise, Optimizing the accuracy of load current / voltage conversion information, optimizing the accuracy of load current information, optimizing the accuracy of current / time product control,
This has the effect of optimizing the accuracy of the overcurrent protection function.

According to the tenth aspect, an effect similar to that of the seventh or eighth aspect is obtained.

According to the eleventh aspect of the present invention, the control unit can directly receive the warning signal from the first type overcurrent protection unit without going through the overcurrent conversion unit. To play.

As a result, the control means performs high-precision current-time product control optimal for the load current when a warning signal is generated by the first type overcurrent protection means. This has the effect that the program can be executed quickly without any intervention.

According to the twelfth aspect of the present invention, in addition to the effect of the eleventh aspect, the control means uses the warning reference potential as the steady-state current upper limit and the first type overcurrent protection means sets the warning current. By generating a signal,
There is an effect that optimal high-precision current-time product control can be executed for the load drive circuit with respect to generation of a load current equal to or larger than the steady-state current upper limit value.

According to the thirteenth aspect, the same effect as the eleventh or twelfth aspect can be obtained.

According to the fourteenth aspect of the present invention, the same effect as any one of the fourth, fifth, sixth, eighth, eleventh, twelfth and thirteenth aspects can be obtained.

According to the fifteenth aspect of the present invention, the provision of the second type overcurrent protection means may cause an overcurrent state or a serious problem in the load drive circuit even if the current flows instantaneously. Even when such an overload current occurs in the load drive circuit, an effect is achieved that such an overload current can be cut off directly and instantaneously without the intervention of the control means.

As a result, there is an effect that an overcurrent protection function having an overcurrent immediate stop function can be realized.

According to the sixteenth aspect of the present invention, in addition to the effect of the fifteenth aspect, even if the current flows momentarily, an overcurrent state or a serious problem may be caused in the load drive circuit. The second kind of overcurrent protection means generates a load current cutoff signal using the load current cutoff reference potential as the instantaneous current upper limit value of the excessive load current. There is an effect that the drive circuit can execute the direct and instantaneous cutoff control.

According to the seventeenth aspect of the invention, in addition to the effects of the fifteenth or sixteenth aspects, even if the current flows momentarily, there is a possibility that an overcurrent state or a serious problem may occur in the load drive circuit. By using the load current cut-off reference potential as the instantaneous current upper limit value of such an excessive load current, by determining whether or not the load current-to-voltage conversion information detected with optimal high precision exists within the instantaneous allowable current range, There is an effect that the load drive circuit can execute the direct and instantaneous cutoff control with optimum high accuracy with respect to the generation of the load current equal to or more than the instantaneous current upper limit value.

According to the eighteenth aspect of the present invention, in addition to the effect of any one of the fourth, fifth, sixth, eighth, fifteenth, and seventeenth aspects, the control means is highly accurate and optimal. There is an effect that the load drive circuit can execute the cutoff control in conjunction with the cutoff control in conjunction with the integrated stepwise current / time product control.

Furthermore, the load drive circuit can execute the cutoff control in conjunction with the stepwise current / time product control that is optimized with high precision for the load current, thereby optimizing the accuracy of the overcurrent protection function. It is possible to achieve the effect of being able to achieve.

According to the nineteenth aspect of the present invention, in addition to the effect of any one of the sixth, fourteenth, and nineteenth aspects, a warning reference potential is used as a steady-state current upper limit value to provide a first-class transient current. By generating a warning signal by the current protection means, it is possible to execute a cut-off control in conjunction with a high-precision current-time product control which is optimal for generation of a load current exceeding the steady-state current upper limit value for the load drive circuit. It has the effect of becoming

According to the twentieth aspect of the present invention, in addition to the effects of any one of the first to nineteenth aspects, overcurrent protection stabilized with high accuracy by using an overcurrent protection device. Load current information is converted from current to voltage within the voltage (= dynamic range) between the ground potential and the power supply potential of the device, and the accuracy of the load current / voltage conversion information can be optimized. As a result, a load drive circuit is generated. There is an effect that the load current is detected and the accuracy of the load current information can be optimized.

Specifically, when the overcurrent protection device takes in the load current information as digital data into itself, it depends on the optimization of the accuracy of the load current / voltage conversion information and the load current information, so that the ground potential-power supply As a result, the load current information can be converted into digital data by A / D conversion within the voltage between the potentials. As a result, highly accurate load current information can be obtained with optimal A / D conversion accuracy. Using the load current information optimized with high accuracy,
There is an effect that the accuracy of the time product control can be optimized.

As a result of optimizing the accuracy of the current-time product control, the current-time product information defined by the product relationship between the continuable time and the load current is compared with the load current detected with optimum high accuracy. As a result, there is an effect that the load drive circuit can determine the load duration time, which is the time during which the load current can be continuously generated, with optimum high accuracy.

Further, based on the load duration time and the current time product information detected with the optimum and high precision as described above, the gate control means performs the step current and time product control optimized with high precision to the load driving circuit. It has the effect of being able to execute.

Further, the overcurrent protection device generates a warning signal using the warning reference potential as the upper limit of the steady-state current. There is an effect that the gate control means can execute the time product control for the load drive circuit.

Further, even if an excessive load current is generated in the load driving circuit which may cause an overcurrent state or a serious problem in the load driving circuit even if the load driving circuit flows instantaneously, it can be directly and instantaneously operated. This has the effect that the gate control means can cut off such an excessive load current. As a result, there is an effect that an overcurrent protection function having an overcurrent immediate stop function can be realized.

According to the twenty-first aspect of the present invention, the load is controlled within the voltage (= dynamic range) between the ground potential and the power supply potential of the overcurrent protection device stabilized with high accuracy using the overcurrent protection device. As a result of current-voltage conversion of the current information and optimization of the accuracy of the load current-voltage conversion information described above, the load current flowing between the source and drain of the power MOSFET is detected to optimize the accuracy of the load current information described above. This has the effect of making it possible.

Specifically, when the overcurrent protection device takes in the load current information as digital data into itself, the overcurrent protection device uses its own ground potential-power As a result, the load current information can be converted into digital data by A / D conversion within the voltage between the potentials. As a result, highly accurate load current information can be obtained with optimal A / D conversion accuracy. Using the load current information optimized with high accuracy,
There is an effect that the accuracy of the time product control can be optimized.

As a result of optimizing the accuracy of the current-time product control, the current-time product information defined by the product relationship between the continuable time and the load current is compared with the load current detected with optimum high accuracy. As a result, there is an effect that the load duration time, which is the time during which the load current can be continuously generated between the source and the drain of the power MOSFET, can be obtained with optimum high accuracy.

Further, based on the load duration time and the current-time product information detected with the optimum and high precision as described above, the gate control means executes the step-wise current / time-product control with high precision and optimization on the power MOSFET. It has the effect of being able to do so.

Further, the overcurrent protection device generates a warning signal using the warning reference potential as the upper limit of the steady-state current. There is an effect that the time control can be performed on the gate of the power MOSFET by the gate control means.

Further, even if the current flows instantaneously, the power MOSFE
Even when an excessive load current which may cause an overcurrent state or a serious failure in T occurs between the source and the drain of the power MOSFET, the power MOSFET
There is an effect that the gate control means can directly and instantaneously control the potential of the gate of T to cut off such an excessive load current. As a result, there is an effect that an overcurrent protection function having an overcurrent immediate stop function can be realized.

According to the twenty-second aspect, the same effect as the twentieth aspect can be obtained.

According to the twenty-third aspect, the same effect as that of the twenty-first aspect is obtained.

[Brief description of the drawings]

FIG. 1 is a circuit diagram for explaining an embodiment of an overcurrent protection device of the present invention.

FIG. 2 is a current-time product characteristic diagram for explaining a stepwise current-time product control executed by a control unit of FIG. 1;

FIG. 3 is a circuit diagram for explaining an embodiment of a semiconductor switch device using the overcurrent protection device of FIG. 1;

FIG. 4 is a circuit diagram for explaining an embodiment of an intelligent power module using the overcurrent protection device of FIG. 1;

FIG. 5 is a circuit diagram for explaining a conventional intelligent power module having an overcurrent protection function.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Intelligent power module 12 Overcurrent conversion means 12A Overcurrent detection part 12B Current / voltage conversion part 12a Load current information 12b Load current / voltage conversion information 14 First type overcurrent protection means 142a Warning signal 142b Warning reference potential 16 Second type overcurrent Protection means 162a Load current cutoff signal 162b Load current cutoff reference potential 18 Boosting means 18a Boosting potential 20 Gate control means 20a Gate input signal 22 Load drive circuit (power MOSFET) 22a Load current 30 Load 32 Control means 32a Current time product information 40 Over Current protection device 42 Constant voltage generation means 50 Semiconductor switch device VB power supply voltage Vcc power supply potential

Claims (23)

[Claims] 1. An overcurrent protection device for detecting a state of a load current generated by a load drive circuit for driving a load, wherein the load current generated by the load drive circuit is detected to output load current information. An overcurrent detection unit; and an overcurrent conversion unit including a current-voltage conversion unit that converts the load current information generated by the overcurrent detection unit into a current-voltage conversion within a predetermined dynamic range and outputs load current-voltage conversion information. An overcurrent protection device, characterized in that: 2. An overcurrent protection device for detecting a state of a load current generated by a load driving circuit for driving a load, wherein the load driving circuit continuously generates the load current and the load current. Control for holding current-time product information having a relationship with the load current, and comparing the load current with the current-time product information to obtain a load duration that is a time during which the load drive circuit can continuously generate the load current. Means for overcurrent protection, comprising: 3. An overcurrent protection device for detecting a state of a load current generated by a load drive circuit for driving a load, wherein a time during which the load drive circuit can continuously generate the load current and the load current While holding current-time product information based on the current-time product relationship represented by the product of the above, the load drive circuit can continuously generate the load current by comparing the load current with the current-time product information. An overcurrent protection device comprising control means for obtaining a load continuation time that is a time. 4. The control means uses the load current / voltage conversion information from the overcurrent conversion means as the load current in the current / time product relation, and uses the load current / voltage conversion information based on the current / time product information to calculate the load current. 4. The current / time product control for performing a control that continues for a load duration time on the load drive circuit is configured to be performed. 5. The method according to claim 1, wherein: Overcurrent protection device. 5. The control means uses the load current / voltage conversion information from the overcurrent conversion means as the load current in the current / time product relationship, and uses the load current based on the current / time product information to calculate the load current. A control that continues for the load duration is executed for the load drive circuit, and the next smaller load current and the next smaller load current can be continued based on the current-time product relationship after the end of the load duration. The load driving circuit is configured to execute a current-time product control for executing control for continuing the load current for the load duration for the load driving circuit by obtaining the load duration. The overcurrent protection device according to any one of claims 1 to 3, wherein 6. The current-time product control executed by the control means, wherein the load-current is changed according to the current-time product relationship in which the load current changes stepwise to the next smaller load current with respect to the load duration. The overcurrent protection device according to claim 4, wherein the current control is stepwise current / time product control. 7. The current-to-voltage conversion unit uses a voltage between a ground potential and a power supply potential of the control unit as the predetermined dynamic range, and uses the load current-voltage conversion information generated by the overcurrent detection unit to the ground. The overcurrent protection according to any one of claims 1 to 6, wherein the current-time product information is generated by performing current-voltage conversion within a voltage between a potential and a power supply potential. apparatus. 8. The control means executes current / time product control using the load current / voltage conversion information having the predetermined dynamic range corresponding to a voltage between its own ground potential and power supply potential. The overcurrent protection device according to claim 7, wherein: 9. A constant voltage generating means for generating a voltage between the ground potential and a power supply potential used as the predetermined dynamic range and for supplying the power supply potential to the control means. Item 10. An overcurrent protection device according to item 7 or 8. 10. A constant voltage generating means for generating a voltage between the ground potential and a power supply potential used as the predetermined dynamic range, and supplying the power supply potential to the control means and the current / voltage converter. The current-voltage converter is configured to convert the load current information into a voltage within the voltage between the ground potential and the power supply potential, generate the load current-voltage conversion information, and output the load current-voltage conversion information to the control unit. The overcurrent protection device according to claim 7 or 8, wherein: 11. An overcurrent protection device for detecting a state of a load current generated by a load driving circuit for driving a load, wherein the load current is within a steady allowable current range in which the load driving circuit can constantly output. Is determined, and when the load current is detected outside the steady allowable current range, the supply state of the load current outside the steady allowable current range is determined as an overcurrent state to determine the overcurrent state. An overcurrent protection device, comprising a first type overcurrent protection means for outputting a warning signal notifying the occurrence of the overcurrent. 12. The first type overcurrent protection means uses a predetermined warning reference potential as a steady current upper limit value which is an upper limit value of the steady allowable current range, and detects the load current equal to or higher than the warning reference potential. The overcurrent protection device according to claim 11, wherein the warning signal is output when the error occurs. 13. The first type overcurrent protection means determines whether the load current / voltage conversion information corresponding to the load current exists within the steady allowable current range, and determines whether the load current / voltage conversion information is outside the steady allowable current range. The overcurrent protection device according to claim 11, wherein the warning signal is output when the load current / voltage conversion information is detected. 14. The control means is configured to, when receiving the warning signal, execute the current-time product control on the load current at the time of generation of the warning signal. The overcurrent protection device according to any one of claims 4, 5, 6, 8, 11, 12, and 13. 15. An overcurrent protection device for detecting a state of a load current generated by a load driving circuit for driving a load, wherein the load current is within an instantaneous allowable current range in which the load driving circuit can output instantaneously. Is determined, and when the load current is detected outside the instantaneous allowable current range, the supply state of the load current outside the instantaneous allowable current range is determined as an overcurrent state, and the overcurrent state is determined. Notifying the occurrence,
An overcurrent protection device comprising: a second type overcurrent protection unit that outputs a load current cutoff signal for prompting a cutoff of supply of a load current outside the instantaneous allowable current range. 16. The type II overcurrent protection means uses a predetermined load current cut-off reference potential as an instantaneous current upper limit value that is an upper limit value of the instantaneous allowable current range, and uses the load current cut-off reference potential equal to or higher than the load current cut-off reference potential. The overcurrent protection device according to claim 15, wherein the overcurrent protection device is configured to output the load current cutoff signal when a current is detected. 17. The second type overcurrent protection means determines whether the load current / voltage conversion information corresponding to the load current exists within the instantaneous allowable current range, and determines whether the load current / voltage conversion information is outside the instantaneous allowable current range. 17. The overcurrent protection device according to claim 15, wherein the overcurrent protection device is configured to output the load current cutoff signal when the load current / voltage conversion information is detected. 18. The apparatus according to claim 18, wherein the control unit is configured to execute the load current cutoff control for the load drive circuit when receiving the load current cutoff signal. 18. The overcurrent protection device according to any one of items 4, 5, 6, 8, 15, 16, and 17. 19. The control means executes the current / time product control on the load current when receiving the load current / voltage conversion information, and executes the current / time product control when receiving the warning signal. Executing the current-time product control for the load current, and executing the load current cut-off control for the load driving circuit when the load current cut-off signal is received. The overcurrent protection device according to any one of claims 6, 14 and 19, wherein: 20. A semiconductor switch device using the overcurrent protection device, wherein the load drive circuit is activated in response to a gate input signal to control the load current and to interrupt the load current. 20. The overcurrent protection device according to any one of claims 1 to 19, further comprising a gate control unit configured to execute cutoff control of the load current to the load drive circuit in accordance with a signal. Semiconductor switch device. 21. The power supply circuit according to claim 21, wherein the load driving circuit is a power MOSFE.
T, wherein the gate control means controls the load current flowing between the source and the drain of the power MOSFET by controlling the potential of the gate of the power MOSFET according to the gate input signal. 21. The semiconductor switch device according to claim 20, wherein the semiconductor switch device is configured to execute cutoff control of a load current flowing between the source and the drain in response to the load current cutoff signal. 22. An intelligent power module using the overcurrent protection device, wherein the load driving circuit, a boosting means for boosting a predetermined power supply voltage to generate a boosted potential, and the load in response to the gate input signal A gate that outputs the boosted potential to a drive circuit, activates the load drive circuit, controls the load current, and executes cutoff control of the load current for the load drive circuit in response to the load current cutoff signal. An intelligent power module using the overcurrent protection device according to any one of claims 1 to 19, further comprising a control unit. 23. The power supply circuit according to claim 23, wherein the load driving circuit is a power MOSFE.
T, wherein the gate control means outputs the boosted potential to the gate of the power MOSFET in response to the gate input signal to control the potential of the gate, so that the source-drain of the power MOSFET 23. The apparatus according to claim 22, wherein the load current flowing between the source and the drain is controlled, and the load current flowing between the source and the drain is cut off in response to the load current cutoff signal. The intelligent power module described.