Abstract: A power supply device sharing power of a doorbell includes two power contacts, an AC switch, an AC/DC conversion circuit, a doorbell actuator, a supply node, an enabling node, and a control node. When the AC switch is off, the AC/DC conversion circuit receives AC power through the two power contacts, generates DC power according to the AC power, and then outputs the generated DC power through the supply node to supply a post-stage circuit for operating. The doorbell actuator is configured to generate an enabling signal and outputting the generated enabling signal through the enabling node. The control node is configured to receive a control signal relative to the enabling signal, to have the AC switch turned on in response to the control signal to ring the doorbell.

Abstract: A power supply device sharing power of a doorbell includes two power contacts, an AC switch, an AC/DC conversion circuit, a doorbell actuator, a supply node, an enabling node, and a control node. When the AC switch is off, the AC/DC conversion circuit receives AC power through the two power contacts, generates DC power according to the AC power, and then outputs the generated DC power through the supply node to supply a post-stage circuit for operating. The doorbell actuator is configured to generate an enabling signal and outputting the generated enabling signal through the enabling node. The control node is configured to receive a control signal relative to the enabling signal, to have the AC switch turned on in response to the control signal to ring the doorbell.

Abstract: A server includes a printed circuit board, a heat sink and a rigid rod. The printed circuit board has a stress concentration zone and a stress dispersion zone around the stress concentration zone. The heat sink is connected to the printed circuit board and located on the stress concentration zone. The rigid rod is connected to the heat sink and fixed on the printed circuit board, and extended across the stress concentration zone and fixed on the stress dispersion zone, so as to reduce the stress forced on the stress concentration zone.