Patent ID: 8299769

Claim:
A multi-output buck converting apparatus with a shutdown protection comprising a main buck converter and at least one auxiliary buck converter to provide multi-output voltages; wherein the main buck converter has a main output terminal to provide a main output voltage to the ground, and the auxiliary buck converter is electrically connected to the main buck converter and has an upper-arm switch, a lower-arm switch, and an auxiliary output terminal to provide an auxiliary output voltage to the ground; the multi-output buck converting apparatus further comprising: an abnormal voltage signal generating unit electrically connected to an input terminal of the main buck converter to generate at least one control signal pair; wherein the control signal pair has an upper-arm control signal and a lower-arm control signal, and the upper-arm control signal and the lower-arm control signal are not at high level simultaneously to control the upper-arm switch and the lower-arm switch, respectively, when the multi-output buck converting apparatus shuts down; whereby the upper-arm switch and the lower-arm switch are controlled to release the energy stored in the auxiliary buck converter through internal discharging paths of the auxiliary buck converter or external loops with connected operational loads so as to avoid returning the energy to the main buck converter and rebounding the main output voltage.