Abstract:
The present invention relates to a voltage converter, which uses an inductor coupled between a power supply and a reference voltage for providing a supply voltage. A plurality of output capacitors are coupled to both sides of the inductor, respectively, and receive the supply voltage for producing a positive voltage and a negative voltage. A plurality of output switches are coupled to both sides of the inductor, respectively, and control the inductor to charge the plurality of output capacitors. A feedback control circuit produces a control signal according to the positive and negative voltages for controlling the plurality of output switches. Thereby, the present invention can produce positive and negative voltage by means of the inductor. Accordingly, the voltage converter according to the present invention avoids usage of multiple inductors and capacitors in producing voltages with different levels, and thus reducing the circuit area as well as the manufacturing cost.
Abstract:
A draining device is disposed within a drain port, which is defined by an upper end of a drain pipe embedded in the ground at an elevation below the ground surface. The draining device includes a tubular base member which has an open upper end, a closed lower end, a bottom wall, and a peripheral wall that extends between the upper and lower ends and that is formed with a plurality of drain openings. A water guiding tube is attached within the base member, and extends into the peripheral wall of the base member. The drain openings of the base member are located around the water guiding tube at an elevation above a lower end of the water guiding tube. The water guiding tube has open upper and lower ends, and is capable of guiding water from the upper end of the base member to the bottom wall of the base member. When water accumulates in a lower end portion of the base member, the water surface thereof is above the lower end of the water guiding tube so as to isolate air in the water guiding tube from air in the drain pipe, thereby preventing insects in the drain pipe from accessing the water guiding tube.