Description
The ACS8526 is a highly integrated single-chip solution for protection switching between two SECs (SDH/SONET Equipment Clocks) from Master and Slave SETS clock cards, for line cards in a PDH, SONET or SDH Network Element. The ACS8526 has fast activity monitors on the inputs and will raise a flag on a pin if there is a loss of activity on the currently selected input. The protection switching between the input reference clock sources is controlled by an external pin.

Features
◆ Line card protection switch - partners Semtech SETS devices for Stratum 3E/3/4E/4 PDH, SONET or SDH applications
◆ High performance DPLL/APLL solution
◆ Output jitter compliant to STM-1
◆ Two independent SEC inputs ports (TTL)
◆ Four independent output ports:
    ◆ Two clock ports: one PECL/LVDS, one TTL
    ◆ Two Syncs (TTL): 8 kHz FrSync & 2 KHz MFrSync
◆ TTL I/O ports: spot frequencies 2 kHz to 77.76 MHz
◆ PECL/LVDS port: spot frequencies 2 kHz to 311 MHz
◆ N x E1/DS1 mode
◆ Programmable pulse width and polarity on Syncs
◆ SONET/SDH frequency translation
◆ Digital Holdover mode on input failure
◆ Separate activity monitors and register alarms on each input.
◆ “Loss of activity” on selected input flagged on dedicated pin
◆ Source switch under external hardware control
◆ PLL “Locked” and “Acquisition” bandwidth selectable from 18, 35 or 70 Hz
◆ Configurable via serial interface or hardware pins
◆ Output clock phase continuity to GR-1244-CORE[13]
◆ Single 3.3 V operation, 5 V I/O compatible
◆ IEEE 1149.1 JTAG Boundary Scan is supported
◆ Operating temperature (ambient) of -40 to +85°C
◆ Available in LQFP 64 package
◆ Lead (Pb)-free version available (ACS8526T), RoHS and WEEE compliant.