Abstract: A heat dissipation device includes a heat spreader (20), a heat sink (10) attached to the heat spreader (20), a sleeve (40) and a heat pipe (30). The heat spreader (20) is for contacting a heat-generating electronic device. The heat sink (10) includes a base (12) and a plurality of fins (14, 15) extending from the base (12). The sleeve (40) is inserted into a through hole (16) defined in the fins (14, 15). The heat pipe (30) includes an evaporating portion (31) sandwiched between the heat spreader (20) and the base (12), and a condensing portion (33) received in the sleeve (40).

Abstract: A heat dissipation device includes a base for absorbing heat from a heat generating device and a first fin set disposed on the base. Two second fin sets are located on two sides of the first fin set and extend beyond the base. At least a heat pipe includes a first section thermally sandwiched between the base and the first fin set and extending totally within and thermally contacting with the two second fin sets, and a second section extending away from the base and thermally contacting the first fin set and the second fin set.

Abstract: An audio amplifier device includes a power supply having an output for providing a supply voltage, a voltage divider connected to the output of the power supply for providing a divided supply voltage, and an audio amplifier that further includes a supply voltage rejection circuit. The audio amplifier has a first input for receiving an input audio signal, a second input for receiving the supply voltage, a third input for receiving a supply voltage rejection signal for the supply voltage rejection circuit, and an output for providing an output audio signal. A power-off noise suppression circuit has a first input for receiving the divided supply voltage and an output for providing the supply voltage rejection signal.

Abstract: A voltage regulator includes a power transistor receiving a drive current, and a current limit protection circuit connected to the power transistor. The current limit protection circuit includes a first resistance connected to the power transistor for sensing an output current, a limit switch transistor connected to the power transistor and to the first resistance, and a current generator and second resistance connected thereto. The current generator and second resistance biases the limit switch transistor to divert drive current from the power transistor based upon the output current through the first resistance exceeding a threshold. The first resistance has a value less than a value of the second resistance. The first resistance can be made considerably smaller than otherwise to thereby reduce power consumption.

Abstract: An audio amplifier device includes a power supply having an output for providing a supply voltage, a voltage divider connected to the output of the power supply for providing a divided supply voltage, and an audio amplifier that further includes a supply voltage rejection circuit. The audio amplifier has a first input for receiving an input audio signal, a second input for receiving the supply voltage, a third input for receiving a supply voltage rejection signal for the supply voltage rejection circuit, and an output for providing an output audio signal. A power-off noise suppression circuit has a first input for receiving the divided supply voltage and an output for providing the supply voltage rejection signal.

Abstract: A voltage regulator includes a power transistor receiving a drive current, and a current limit protection circuit connected to the power transistor. The current limit protection circuit includes a first resistance connected to the power transistor for sensing an output current, a limit switch transistor connected to the power transistor and to the first resistance, and a current generator and second resistance connected thereto. The current generator and second resistance biases the limit switch transistor to divert drive current from the power transistor based upon the output current through the first resistance exceeding a threshold. The first resistance has a value less than a value of the second resistance. The first resistance can be made considerably smaller than otherwise to thereby reduce power consumption.