Patent ID: 8570018

Claim:
A hot swappable synchronous buck regulator, comprising: a voltage regulator comprising a voltage input terminal and a voltage output terminal, the voltage input terminal being configured for connected to an external power source, the voltage regulator configured for converting voltage of the external power source into a predetermined output voltage and outputting the predetermined output voltage through the output terminal; a sample unit comprising a first end and a second end, the first end being connected to the external power source, the sample unit configured for sampling a voltage drop of the external power source; a switch element comprising a first terminal, a second terminal connected to the first terminal, and a control terminal, the first terminal being connected to the second end of the sample unit, the second terminal being connected to the voltage input terminal of the voltage regulator; a comparison unit connected to the second end of the sample unit and configured for comparing the sampled voltage drop with a first reference voltage of the voltage regulator, and in response to the sampled voltage drop being greater than the first reference voltage, the comparison unit outputs a result-high signal; a time delay unit connected to the comparison unit and configured for outputting a result-low signal according to the result-high signal; and a control unit connected to the time delay unit and configured for outputting a low level signal to the control terminal of the switch element according to the result-low signal; wherein the switch element isolates the external power source from the voltage regulator when the control terminal of the switch element receives the low level signal.