| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an overcurrent protection circuit capable of efficiently protecting damages of a power driver due to an overcurrent while effectively utilizing the current-resistance capability of the power driver to regulate energization of the power driver. <P>SOLUTION: The overcurrent protection circuit 11 includes a current-value decision circuit 10 capable of determining a magnitude between the overcurrent Iv running through a low-side FET 2 and a current threshold, when the time set in a timer elapses since the overcurrent Iv is generated in the low-side FET 2. The overcurrent protection circuit stops the on/off operation of the low-side FET 2 when the overcurrent Iv exceeds the current threshold. Further, the overcurrent protection circuit includes a resistor 12 for measuring the temperature rise at the low-side FET 2 to shorten the time in the timer as the temperature rises higher when the over current Iv at the low-side FET 2 detected by the resistor 12 for measuring the temperature rise. <P>COPYRIGHT: (C)2010,JPO&INPIT |
