Abstract: A phase locked loop (PLL) circuit is provided with selectable feedback paths. In one example, a method of operating a device includes passing a clock signal provided by a PLL circuit of the device through an internal feedback path of the PLL circuit to provide a first input signal to the PLL circuit while at least one external circuit of an external feedback path of the device is disabled during a low power operation mode of the device. The method also includes detecting a lock between the first input signal and a reference signal during the low power operation mode. The lock indicates that the clock signal is operating at a frequency used during a normal operation mode of the device. The method also includes passing the clock signal through the external feedback path to provide a second input signal to the PLL circuit.

Abstract: A buffer for a programmable logic device has programmable current sink and source circuitry and an independently programmable common-mode voltage reference source. An amplifier, responsive to a common-mode voltage detector and the voltage reference source, forces a common-mode voltage of an output signal from the buffer to approximate the voltage from the common-mode voltage reference source.

Abstract: Apparatus for fastening includes a linkage and a body. The linkage has an end enlarged to form a ball. The body forms a carabineer's hook. A side of the body has a guideway which is open at a side and at an end of the body. Most of the guideway is dimensioned to receive the linkage, but not the ball. Near the end of the body, the guideway forms a dock which opens at the side, wide enough to receive the ball. A slide is held in the guideway and has a fork dimensioned to receive the linkage while blocking the ball. The slide is movable toward and away from said end so that the fork alternately uncovers and partially covers the dock, alternately confining and releasing the ball. The linkage is free to rotate through at least 90 degrees, from parallel to the guideway to normal to the side, while the fork confines the ball in the dock. Optionally, the linkage in hingedly connected to a pedestal adapted for attachment to objects.

Abstract: A clock generator has a reset circuit and (at least) two dividers, where each divider divides a reference clock signal by a divisor value to generate an output clock signal. The reset circuit generates reset signals for the dividers, where the reset signals are delayed relative to one another by a selected number of reference clock cycles, such that the dividers generate output clock signals having a desired phase offset between them.

Abstract: A buffer for a programmable device has source current circuitry, sink current circuitry, one or more input nodes, one or more output nodes, and switch circuitry. The source current circuitry can be programmably controlled to generate a plurality of different total source currents, and the sink current circuitry can be programmably controlled to generate a plurality of different total sink currents. The one or more input nodes can receive one or more input signals, and the one or more output nodes can present one or more output signals. The switch circuitry can selectively apply at least one of a total source current and a total sink current to the one or more output nodes based on the one or more input signals.

Abstract: A side entry life vest has buckles disposed on the ventral panel and belts retained in horizontal tubes formed in the dorsal panel. The likelihood that a wearer may don the vest backwards is minimized because the buckles would be beyond the person's comfortable reach, and the person would immediately sense that the vest is backwards. The belts extend substantially the entire width of the dorsal panel and both maximize belt retention strength and provide a flat area on which to display a sponsor's name, logo or other information.

Abstract: A lightweight hand-operated aircraft tug for small aircraft includes a main frame upon which a drive drum is movably mounted for engagement with the wheel of an aircraft. A reversible pawl and rachet or an equivalent device controls the direction of rotation of the drum. A lever arm controls the engagement and disengagement of the drum with the aircraft wheel. A pair of axle-engaging inserts are associated with the main frame of the tug so as to be engageable with the axle of the aircraft when the drum is driven into engagement with the wheel by the operation of the lever arm.