SNAS689A October 2017 – July 2019 LMK04228
PRODUCTION DATA.
The global SYSREF divider includes a digital delay block which allows a global phase shift with respect to the other clocks.
Each local SYSREF clock output includes both an analog and additional local digital delay for unique phase adjustment of each SYSREF clock.
The local analog delay allows for 150-ps steps, ranging from 600 ps to 2700 ps of granular delay. Enabling the analog delay path adds a nominal 700 ps of delay in addition to the programmed value, and the first delay value adds 600 ps.
The local digital delay and SYSREF_HS bit allows the each individual SYSREF output to be delayed from 1.5 to 11 VCO cycles. The delay step can be as small as half the period of the clock distribution path by using the DCLKoutX_HS bit. For example, 2-GHz VCO frequency results in 250-ps coarse tuning steps.