| 摘要 |
PROBLEM TO BE SOLVED: To avoid the phenomena of a large current flowing and oscillating phenomena by detecting short circuit surely even in the case of having tried to start a digital camera in condition that the voltage supplied to a switching regulator controller is short-circuited when battery voltage drops. SOLUTION: For a digital camera, a circuit for operating the short circuit detecting action of a switching regulator controller 104, using the voltages different in starting speed, is added, whereby the digital camera is started normally by operating the short circuit detecting circuit at power on and stopping the short circuit detecting action before it reaches the threshold level of short circuit detection at normality, and at short circuit, the operation of the switching regulator is stopped surely before the voltage of the switching regulator drops to the lowest operation voltage, thereby preventing a large current from flowing. COPYRIGHT: (C)2007,JPO&INPIT |
