AD800

a FEATURES Standard Products 44.736 Mbps—DS-3 51.84 Mbps—STS-1 155.52 Mbps—STS-3 or STM-1 Accepts NRZ Data, No Preamble Required Recovered Clock and Retimed Data Outputs Phase-Locked Loop Type Clock Recovery—No Crystal Required Random Jitter: 20؇ Peak-to-Peak Pattern Jitter: Virtually Eliminated 10KH ECL Compatible Single Supply Operation: –5.2 V or +5 V Wide Operating Temperature Range: –40؇C to +85 ؇C Clock Recovery and Data Retiming Phase-Locked Loop AD800/AD802* FUNCTIONAL BLOCK DIAGRAM CD DATA INPUT ØDET COMPENSATING ZERO ∑ LOOP FILTER VCO fDET RETIMING DEVICE RECOVERED CLOCK OUTPUT RETIMED DATA OUTPUT AD800/AD802 FRAC OUTPUT PRODUCT DESCRIPTION The AD800 and AD802 employ a second order phase-locked loop architecture to perform clock recovery and data retiming on Non-Return to Zero, NRZ, data. This architecture is capable of supporting data rates between 20 Mbps and 160 Mbps. The products described here have been defined to work with standard telecommunications bit rates. 45 Mbps DS-3 and 52 Mbps STS-1 are supported by the AD800-45 and AD800-52 respectively. 155 Mbps STS-3 or STM-1 are supported by the AD802-155. Unlike other PLL-based clock recovery circuits, these devices do not require a preamble or an external VCXO to lock onto input data. The circuit acquires frequency and phase lock using two control loops. The frequency acquisition control loop initially acquires the clock frequency of the input data. The phase-lock loop then acquires the phase of the in...