SY87721LHG

Application Specific Clock/Timing Overview

The SY87721LHG is a Clock and Data Recovery (CDR) integrated circuit manufactured by Micrel, Inc. It supports NRZ data rates from 28 Mbps to 2.7 Gbps and includes an integrated Clock Multiplier Unit (CMU). The device recovers embedded clocks via a VCO synchronized to the incoming data stream. It operates on a single 3.3V supply with typical current consumption of 360 mA. The unit is housed in a 64-lead EPAD-TQFP package and functions within an industrial temperature range of -40°C to +85°C.

Application Specific Clock/Timing Feature Summary

• Recovers any data rate from 28 Mbps to 2.7 Gbps using AnyRate technology
• Integrated Clock Multiplier Unit (CMU) for low jitter clock generation
• Selectable multiplexer for pass-through mode to avoid jitter accumulation
• Supports SONET/SDH, ATM, Gigabit Ethernet, Fibre Channel, and P1394

Application Specific Clock/Timing Applications

• SONET/SDH/ATM transmission systems and test equipment
• Transponders and section repeaters
• Multiplexers including access, add-drop (ADM), and terminal (TM)
• Terabit routers and broadband cross-connects
• Fiber optic test equipment

Application Specific Clock/Timing Procurement Notes

Verify component authenticity through authorized channels as the original manufacturer Micrel was acquired by Microchip Technology. Confirm lead finish specifications; the HG suffix indicates a Pb-Free variant with NiPdAu finish. Ensure compliance with RoHS directives if required for the specific application environment.

Application Specific Clock/Timing Selection Notes

Select this component when designing systems requiring flexible data rate recovery up to 2.7 Gbps without fixed frequency constraints. Ensure the design accommodates the 3.3V power supply requirement and provides adequate thermal management for the 64-pin TQFP package. Verify that external loop filter components match the recommended values for narrow and wide band PLLs.

Application Specific Clock/Timing Part Context

This part belongs to the SY87721L series of AnyRate CDRs. The 'HG' suffix specifically denotes the Pb-Free version with a NiPdAu lead finish, intended for new designs. It is functionally equivalent to the standard Sn-Pb version but adheres to environmental regulations regarding restricted substances.

Application Specific Clock/Timing Replacement Considerations

Direct replacement requires verifying pin compatibility and electrical characteristics against the standard SY87721LHI. If Pb-free compliance is mandatory, ensure the substitute also carries the appropriate RoHS certification and lead finish specifications.