Digital delay system and method for digital cross connect telecommunication systems

DETAILED DESCRIPTION The present invention provides a digital delay system and method for a digital cross connect system that substantially eliminates or reduces disadvantages and problems associated with previously developed delay line systems and methods.
More specifically, the present invention provides a system and method for generating a plurality of clock phases from a clock signal in a telecommunications cross connect system.
The digital delay circuit of the present invention includes a plurality of delay elements, a plurality of sampling elements, and a multiplexor.
The total number of delay elements comprises a number that produces a worst case delay equal to or greater than the period of the clock signal.
The delay elements receive the rising edge of the clock signal.
The delayed rising edges are sent to the sampling elements.
The sampling elements send outputs to the multiplexor to determine the number of delay elements transitioned by one cycle of the clock signal.
In a further aspect of the present invention, a programming device is coupled to the multiplexor to request from the multiplexor a particular phase of the clock signal.
The programming device can receive a request for a particular phase of the clock signal to be generated, divide the number of delay devices transitioned by the binary number representing the requested phase to determine an appropriate delay device at which that phase exists, and instruct the multiplexor to select the appropriate delay device so that the multiplexor generates the requested phase.
The present invention provides an important technical advantage by eliminating the analog delay lines currently used to generate a particular phase of a given clock.
The present invention provides another technical advantage by reducing the cost, complexity, and inaccuracies associated with analog delay lines used in conventional digital cross connect systems to generate a particular phase of a clock.