Picosecond programmable delay line using commercial components for precision timing signal alignment

Abstract

A picosecond precision programmable digital delay line with 10 ps average resolution and 200 ns range using low-cost, commercially available integrated circuits (MC100EP195 and DS1023) is presented. This design is integrated into an existing product (AOG-110 from Microchip Technology Inc.) to facilitate alignment between 1 PPS and 5 MHz output waveforms based on user selected features (e.g. zero-crossings or peak amplitudes) for precision-timing applications. The performance of this design is experimentally validated using logarithmic stepped delays from 10 ps to 200 ns with a median deviation of 1.9% from the ideal. The largest deviations are observed in the range from 10 ps to 100 ps, attributed to the non-linear behavior of the MC100EP195 in the design. Overall, this design is a low-cost, digital delay option that can be easily integrated into any microcontroller based system and does not require additional complex design revisions. Further, this highlights the increased range and precision options available by cascading commercially available digital delay line integrated circuits.