Abstract: An output of a first data register is coupled to an input of a second data register. The same periodic clock signal clocks both data registers. A controller monitors the clock signal, a first load signal and a read signal. The controller generates a guard band signal using the clock signal and the first load signal. The controller also generates a second guard band signal from the read signal and the clock signal. A second load signal, that is used to load the second data register, is created by performing a logical AND operation on the two guard band signals.

Abstract: A port isolator apparatus includes an optical isolator circuit that electrically isolates an input circuit from a high-speed output circuit. The input circuit uses a transistor to control the current flow of a data signal into the optical isolator. The optical isolator generates, from the data signal, an output signal that controls the high-speed output circuit in the regeneration of the output signal. The output signal is substantially similar to the input data signal. The input circuit and the optical isolator circuit are coupled to one power and ground circuit while the high-speed output circuit is coupled to a second power and ground circuit that is isolated from the first power and ground circuit.

Abstract: A method for controlling fan operation that includes detecting a stopped fan and attempting to start the stopped fan. The method includes attempting to start the stopped fan again after at least one first time interval when the fan does not start. The method includes attempting to start the stopped fan again after at least one second time interval when the fan does not start after a predetermined number of first time intervals, where the at least one second time interval is longer than the first time interval.

Abstract: A circuit card that includes a single ground plane connectable to a chassis-ground and a logic device having a ground pin connected to the single ground plane. The connection between the ground pin and the single ground plane provides a direct path between the logic device and the chassis-ground. A power supply is connected to an input pin of the logic device for providing a logic voltage to the logic device. The power supply is connectable to a battery.

Abstract: An electronic module having a chassis and a single backplane disposed within the chassis. A plurality of bridge circuit cards is disposed within the chassis and is electrically connected to the single backplane. Each of the plurality of bridge circuit cards is for converting between a local area network protocol and a wide area network protocol. A hub circuit card is disposed within the chassis and is electrically connected to the single backplane so that the hub circuit card is electrically connected to each of the plurality of bridge circuit cards. The single backplane is connectable to each of a plurality of remote units for respectively electrically connecting each of the plurality of remote units to each of the plurality of bridge circuit cards. The single backplane is connectable to a data network for electrically connecting the data network to the hub circuit card.

Abstract: A port isolator apparatus includes an optical isolator circuit that electrically isolates an input circuit from a high-speed output circuit. The input circuit uses a transistor to control the current flow of a data signal into the optical isolator. The optical isolator generates, from the data signal, an output signal that controls the high-speed output circuit in the regeneration of the output signal. The output signal is substantially similar to the input data signal. The input circuit and the optical isolator circuit are coupled to one power and ground circuit while the high-speed output circuit is coupled to a second power and ground circuit that is isolated from the first power and ground circuit.

Abstract: An output of a first data register is coupled to an input of a second data register. The same periodic clock signal clocks both data registers. A controller monitors the clock signal, a first load signal and a read signal. The controller generates a guard band signal using the clock signal and the first load signal. The controller also generates a second guard band signal from the read signal and the clock signal. A second load signal, that is used to load the second data register, is created by performing a logical AND operation on the two guard band signals.

Abstract: An electronic module having a chassis and a single backplane disposed within the chassis. A plurality of bridge circuit cards is disposed within the chassis and is electrically connected to the single backplane. Each of the plurality of bridge circuit cards is for converting between a local area network protocol and a wide area network protocol. A hub circuit card is disposed within the chassis and is electrically connected to the single backplane so that the hub circuit card is electrically connected to each of the plurality of bridge circuit cards. The single backplane is connectable to each of a plurality of remote units for respectively electrically connecting each of the plurality of remote units to each of the plurality of bridge circuit cards. The single backplane is connectable to a data network for electrically connecting the data network to the hub circuit card.

Abstract: A modular fan unit having a frame receivable within a baffle of a chassis for containing electronic components is provided. Each of a pair of brackets is connected to an end of the frame to form a slot for receiving a wall of the baffle. Moreover, each of the pair of brackets is respectively attachable to a pair of walls of a rack containing the chassis. A fan is attached to the frame so as to align with an aperture located between the pair of brackets and passing through the frame. A controller is attached to the frame and is electrically connected to the fan.

Abstract: A method for controlling fan operation that includes detecting a stopped fan and attempting to start the stopped fan. The method includes attempting to start the stopped fan again after at least one first time interval when the fan does not start. The method includes attempting to start the stopped fan again after at least one second time interval when the fan does not start after a predetermined number of first time intervals, where the at least one second time interval is longer than the first time interval.

Abstract: A modular fan unit having a frame receivable within a baffle of a chassis for containing electronic components is provided. Each of a pair of brackets is connected to an end of the frame to form a slot for receiving a wall of the baffle. Moreover, each of the pair of brackets is respectively attachable to a pair of walls of a rack containing the chassis. A fan is attached to the frame so as to align with an aperture located between the pair of brackets and passing through the frame. A controller is attached to the frame and is electrically connected to the fan.

Abstract: An electronic module having a circuit card with a power supply is provided. The electronic module has two independent battery-return paths. One of the two independent battery-return paths is connectable to a battery-return side of a primary battery, and another of the two independent battery-return paths is connectable to a battery-return side of a secondary battery that replaces the primary battery when the primary battery fails. The two independent battery-return paths are connected together at a battery-return pin of the power supply.

Abstract: A circuit card that includes a single ground plane connectable to a chassis-ground and a logic device having a ground pin connected to the single ground plane. The connection between the ground pin and the single ground plane provides a direct path between the logic device and the chassis-ground. A power supply is connected to an input pin of the logic device for providing a logic voltage to the logic device. The power supply is connectable to a battery.

Abstract: A fan module having a frame is provided. A fan is disposed within and attached to the frame so as to align with an aperture passing through the frame. A baffle having first and second inclined surfaces in opposition is disposed within the frame. The first surface is for changing the direction of a first fluid flow from the fan, and the second surface is for changing the direction of a second fluid flow so as to direct the second fluid flow through an exit of the fan module.