| 摘要 |
A synchronous buck regulator includes a voltage regulator, a sample unit, a switch element, a comparison unit, a time delay unit, and a control unit. The sample unit is connected to the external power source for sampling a voltage drop in the external power source. The comparison unit is connected to the sample unit for outputting a result-high signal when the current passing through the sample unit is greater than a predetermined current rating. The time delay unit is connected to the comparison unit for outputting a first result-low signal. The control unit is connected to the time delay unit and outputs a first a low level signal to the switch element according to the result-low signal. The switch element connects the sample unit and the voltage regulator and can isolate the voltage regulator from the external power source when the low level signal is received. |
