Patent ID: 7864495
Filing Date: 2011-01-04
Classification: H01L,H02H

Abstract:
1. A protection circuit configured to shut off an input voltage to a predetermined circuit when the input voltage becomes higher than or equal to a predetermined voltage, the protection circuit comprising: a switch configured to be one of turned on so as to allow the input voltage to be output to the predetermined circuit, and turned off so as to stop the input voltage from being output to the predetermined circuit; a detection circuit portion configured to detect the input voltage and cause the switch to be turned off when the detected voltage is higher than or equal to the predetermined voltage; a reduced voltage generation circuit portion configured to generate a reduced voltage in accordance with the input voltage and output the reduced voltage to the predetermined circuit when the switch is turned off; and an excess voltage detection signal generation circuit portion that generates an excess voltage detection signal indicating that the input voltage is higher than or equal to the predetermined voltage and outputs the excess voltage detection signal to the predetermined circuit when the input voltage detection circuit portion causes the switch to be turned off.