Abstract: A hot-plug circuit for receiving a high-current load is disclosed. In accordance with a preferred embodiment of the present invention, the hot-plug circuit comprises a transistor, a capacitor, a resistor, and a control circuit module. The transistor is coupled between a power supply and an input that is adapted to receive the high-power adaptor card. The capacitor is coupled between a first terminal and a second terminal of the transistor. The resistor is coupled to the first terminal of the transistor. Finally, the control circuit module is for applying a first bias voltage to the second terminal of the transistor via the resistor in order to turn the transistor off during an absence of the high-current load, and for applying a second bias voltage to the second terminal of the transistor via the resistor in order to turn the transistor on under a linear conduction mode upon an initial contact of said high-current load to the input.

Abstract: A noise dithering system provides gating signals to switching transistors that selectively apply power to an output device in response to the gating signals, wherein said gating signals include a selected level of frequency modulation insufficient to alter operational characteristics of the output device more than a predetermined amount. One embodiment concerns a PWM switching system in which a PWM controller provides gating signals to switching transistors, where the gating signals are clocked by a timing circuit in accordance with a modulated input reactance sensed by a timing input node. In another embodiment, the gating signals may be clocked by the timing circuit in accordance with a modulated current at a timing input node, provided by a variable current source. In the case of the modulated input reactance, a voltage variable capacitor is preferably used to provide a capacitance proportional to output of a modulator.