METHODS AND SYSTEMS FOR REDUCING SUPPLY AND TERMINATION NOISE IN PROGRAMMABLE DELAY LINES

摘要

Described are integrated-circuit delay lines that include regulated and unregulated delay elements connected in series. The regulated delay elements exhibit relatively long delays that are stable over process, voltage, and temperature. The unregulated delay elements exhibit relatively short delays with fine adjustment granularity. A multiplexer selects various numbers of the delay elements to provide a range of delay settings. The multiplexer includes a number of smaller multiplexers cascaded to minimize the lead-in delay of the delay element. The delay elements and multiplexer can be single-ended or complementary.