ACS8522A Datasheet | SEMTECH

ACS8522A SETS LITE Synchronous Equipment Timing Source for Stratum 3/4E/4 and SMC Systems MUNICATIONS ADVANCED MS & SENSING .. Description FINAL Features The ACS8522A is a highly integrated, single-chip solution for the Synchronous Equipment Timing Source (SETS) function in a SONET or SDH Network Element. The device generates SONET or SDH Equipment Clocks (SEC) and Frame Synchronization clocks. The ACS8522A is fully pliant with the required international specifications and standards. The device supports Free-run, Locked and Holdover modes, with mode selection controlled either automatically by an internal state machine or forced by register configuration. The ACS8522A accepts up to four independent input SEC reference clock sources from Recovered Line Clock, PDH network, and Node Synchronization. The ACS8522A generates independent SEC and BITS clocks, an 8 k Hz Frame Synchronization clock and a 2 k Hz Multi-Frame Synchronization clock, both with programmable pulse width and polarity. The ACS8522A includes a Serial Port, which can be SPI patible, providing access to the configuration and status registers for device setup. The ACS8522A supports IEEE 1149.1 [5] ‹ Suitable for Stratum 3, 4E, 4 and SONET Minimum Clock (SMC) or SONET/SDH Equipment Clock (SEC) applications (to Telcordia 1244-CORE[19] Stratum 3 and GR-253[17], and ITU-T G.813[11] Options Ι and ΙΙ specifications). ‹ Accepts four individual input reference clocks, all with robust input clock source quality monitoring. ‹ Simultaneously generates four output clocks, plus two Sync pulse outputs. ‹ Absolute Holdover accuracy better than 3 x 10-10 (manual), 7.5 x 10-14 (instantaneous); Holdover stability defined by choice of external XO. ‹ Programmable PLL bandwidth, for wander and jitter tracking/attenuation, 0.1 Hz to 70 Hz in 10 steps. ‹ Automatic hit-less source switchover on loss of input ‹ Serial SPI patible interface. ‹ Output phase adjustment in 6 ps steps up...