Abstract: A wide range power supply capable of delivering 20V to 5000V is provided. The power supply of the present invention uses switch mode technology to achieve high overall operating efficiency and is capable of operating from no load to full load without loss of regulation. The power supply in accordance with the embodiments of the present invention operates directly from the utility supply (e.g., 110V/220V and 50 Hz/60 Hz). In one embodiment, the power supply's power conversion stage includes the following stages: an input rectifier; a buck converter; a quasi-resonant inverter; and a voltage multiplier. The above indicated stages are connected in series to achieve the large output voltage range. High precision is obtained from a use of a digital feedback loop, possibly in connection with an analog feedback loop.

Abstract: A wide range power supply capable of delivering 20V to 5000V is provided. The power supply of the present invention uses switch mode technology to achieve high overall operating efficiency and is capable of operating from no load to full load without loss of regulation. The power supply in accordance with the embodiments of the present invention operates directly from the utility supply (e.g., 110V/220V and 50 Hz/60 Hz). In one embodiment, the power supply's power conversion stage includes the following stages: an input rectifier; a buck converter; a quasi-resonant inverter; and a voltage multiplier. The above indicated stages are connected in series to achieve the large output voltage range. High precision is obtained from a use of a digital feedback loop, possibly in connection with an analog feedback loop.

Abstract: A cap which is self-adjusting within a predetermined range of hat sizes, includes a crown having a dome and a continuous lower rim formed of a flexible substantially inelastic material. The crown has a front portion and a rear portion together having a fully expanded size corresponding to a maximum size at least as large as a largest hat size within the predetermined range of hat sizes. An elastic strip having a rear portion is attached to the front portion of the rim so that an unstretched rear portion produces an elastic loop. The size of the loop and the front portion of the rim combine to form an unstretched size which is at least as small as a minimum hat size within the predetermined range of hat sizes. The elastic strip has a partially stretched length resulting in a size together with the front rim portion, which corresponds to the maximum size of the lower rim which is at least as large as the largest hat size within the range of hat sizes.