Semiconductor device which realizes a short-circuit protection function without shunt resistor, and semiconductor device module
View Patent ↗A control output signal is supplied to a gate electrode of an insulated gate transistor from a control signal output terminal of a control device, however, with regard to the insulated gate transistor, a control output signal is also influenced when that transistor is short-circuited, and a signal waveform different from that in a normal operating state occurs. The short-circuit is detected by monitoring the control output signal of the insulated gate transistor, and in case of the short-circuit, the short-circuit protection of the insulated gate transistor is performed by forcing the control device to stop that control output signal.
1. A semiconductor device controlling a drive of an insulated gate transistor by generating a control output signal on a basis of a control input signal, comprising:
a driver outputting said control output signal and
a short-circuit protection circuit detecting said control output signal and controlling and forcing said driver to stop said control output signal when a detecting voltage of said control output signal exceeds a predetermined reference voltage before a predetermined period passes after said control output signal indicates a conduction of said insulated gate transistor, wherein
said short-circuit protection circuit includes:
pulse generation circuit receiving said control input signal and outputting a first pulse signal being significant only in said predetermined period according to a timing when said control input signal indicates the conduction of said insulated gate transistor;
a comparator receiving the detecting voltage of said control output signal, performing a comparison with said reference voltage and outputting a second pulse signal being significant during a period when the detecting voltage of said control output signal exceeds said reference voltage; and
a logical circuit receiving said first and second pulse signals and outputting a stop signal forcing said driver to stop said control output signal when said second pulse signal becomes significant during a period when said first pulse signal is significant.
2. The semiconductor device according to claim 1 , wherein
said predetermined period when said first pulse signal is significant is set on a basis of a period when a voltage of said control output signal is clamped constantly when said insulated gate transistor normally operates.
3. A semiconductor device module, comprising:
at least one set of first and second insulated gate transistors inserted in series between a high potential first main power terminal and a low potential second main power terminal and complementarily operating;
a first control device controlling a drive of said first insulated gate transistor of a high potential side; and
a second control device controlling a drive of said second insulated gate transistor of a low potential side, wherein
said at least one set of first and second insulated gate transistors and said first and said second control devices are sealed with a resin in a package and
said semiconductor device according to claim 1 is employed as said second control device and
said second insulated gate transistor is controlled as said insulated gate transistor.
4. A semiconductor device controlling a drive of an insulated gate transistor by generating a control output signal on a basis of a control input signal, comprising:
a driver outputting said control output signal and
a short-circuit protection circuit detecting said control output signal and controlling and forcing said driver to stop said control output signal when a detecting voltage of said control output signal exceeds a predetermined reference voltage before a predetermined period passes after said control output signal indicates a conduction of said insulated gate transistor, wherein
said short-circuit protection circuit includes:
pulse generation circuit receiving said control input signal and outputting a first pulse signal being significant only in said predetermined period according to a timing when said control input signal indicates the conduction of said insulated gate transistor;
a signal selective part receiving the detecting voltage of said control output signal and a predetermined voltage lower than said reference voltage and selectively outputting one of them on a basis of said first pulse signal; and
a comparator receiving said output of said signal selective part, performing a comparison with said reference voltage and outputting a second pulse signal being significant during a period when said output of said signal selective part exceeds said reference voltage, wherein
said signal selective part receives said first pulse signal, selects and outputs the detecting voltage of said control output signal during a period when said first pulse signal is significant and selects and outputs the predetermined voltage lower than said reference voltage during a period when said first pulse signal is not significant,
said comparator receives the detecting voltage of said control output signal only in the period when said first pulse signal is significant and makes said second pulse signal significant in case that the detecting voltage of said control output signal exceeds said reference voltage and
said second pulse signal functions as a stop signal forcing said driver to stop said control output signal when said second pulse signal is significant.
5. The semiconductor device according to claim 4 , wherein
the detecting voltage of said control output signal is detected by a divided resistance connected in series between an output terminal of said driver and a reference potential.
6. The semiconductor device according to claim 4 , wherein
said predetermined period when said first pulse signal is significant is set on a basis of a period when a voltage of said control output signal is clamped constantly when said insulated gate transistor normally operates.
7. A semiconductor device module, comprising:
at least one set of first and second insulated gate transistors inserted in series between a high potential first main power terminal and a low potential second main power terminal and complementarily operating;
a first control device controlling a drive of said first insulated gate transistor of a high potential side; and
a second control device controlling a drive of said second insulated gate transistor of a low potential side, wherein
said at least one set of first and second insulated gate transistors and said first and said second control devices are sealed with a resin in a package and
said semiconductor device according to claim 4 is employed as said second control device and
said second insulated gate transistor is controlled as said insulated gate transistor.
8. A semiconductor device module, comprising:
at least one set of first and second insulated gate transistors inserted in series between a high potential first main power terminal and a low potential second main power terminal and complementarily operating;
a first control device controlling a drive of said first insulated gate transistor of a high potential side; and
a second control device controlling a drive of said second insulated gate transistor of a low potential side, wherein
said at least one set of first and second insulated gate transistors and said first and said second control devices are sealed with a resin in a package and
said semiconductor device according to claim 5 is employed as said first control device and
said first insulated gate transistor is controlled as said insulated gate transistor.