| 摘要 |
PROBLEM TO BE SOLVED: To protect a voltage driving element and a shunt resistor when a terminal is short-circuited. SOLUTION: A short-circuit protecting circuit is provided with the voltage driving element 10 connected to the terminal T1 at one end and grounded at the other end through the shunt resistor Rs, a detection circuit 20 for detecting a voltage across the shunt resistor Rs, and a drive circuit 30 for controlling and turning on/off the voltage driving element 10 based on a voltage detection signal from the detection circuit 20. A current flows to the shunt resistor Rs, and the detection circuit 20 detects the voltage by connecting a resistance element R1 having resistance larger than that of the shunt resistor Rs to the voltage driving element 10 in parallel when the voltage driving element 10 is turned off. When the terminal T1 is short-circuited, the drive circuit 30 is controlled so as not to turn on the voltage driving element 10. COPYRIGHT: (C)2007,JPO&INPIT
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