Patent ID: 8384366

Claim:
A controller for a power system, the controller comprising: a first resistor including a first resistor terminal and a second resistor terminal, the first resistor terminal configured to receive a first voltage signal, the second resistor terminal being connected to a first circuit node; a first transistor including a first transistor terminal, a second transistor terminal, and a third transistor terminal, the first transistor terminal being configured to receive a second voltage signal from the first circuit node, the second transistor terminal being configured to receive a third voltage signal from a second circuit node, the third transistor terminal being connected to a third circuit node; a second resistor including a third resistor terminal and a fourth resistor terminal, the third resistor terminal being connected to the second circuit node; a third resistor including a fifth resistor terminal and a sixth resistor terminal, the fifth resistor terminal being connected to the fourth resistor terminal through a fourth circuit node, the sixth resistor terminal being connected to the third circuit node; a second transistor including a fourth transistor terminal, a fifth transistor terminal, and a sixth transistor terminal, the fourth transistor terminal being connected to the second circuit node, the sixth transistor terminal being connected to the third circuit node; a voltage regulator configured to receive at least the first voltage signal and to convert the first voltage signal to a fourth voltage signal, the fourth voltage signal being smaller than the first voltage signal in magnitude; a threshold voltage generator configured to receive the fourth voltage signal and to generate a threshold voltage signal; a voltage comparator configured to receive the threshold voltage signal and a fifth voltage signal from the fourth circuit node, compare the threshold voltage signal and the fifth voltage signal, and to generate a comparison signal; and a timer configured to receive the comparison signal, provide a delay time, and output a sixth voltage signal.