SY87700LHI - 3.3V 175Mbps AnyRate CDR | Microchip Technology

SONET Line-Card Timing Recovery

The SY87700LHI fits SONET line-card timing blocks because it combines clock generation and clock-and-data recovery for 32Mbps to 175Mbps NRZ streams. According to the Microchip Technology product information, the device supports SONET/SDH systems and uses two on-chip PLLs, allowing one recovery path and one generation path to share a compact timing architecture. Its 3.3V supply and 32-pin TQFP-EP package reduce board-area requirements compared with multiple discrete timing devices. The principal engineering check is the recovered jitter and lock behavior at the exact SONET tributary rate; neither value was included in the supplied extracts and must be confirmed from the manufacturer datasheet. PECL routing also requires controlled impedance and terminations designed according to the device interface specifications.

SDH Transport Equipment

The SY87700LHI can support SDH transport equipment requiring extraction of a stable clock from an incoming NRZ data stream. Its verified 32Mbps-to-175Mbps operating range covers the rate envelope associated with the stated SONET/SDH use case, while the two internal PLLs provide dedicated resources for clock generation and clock recovery. This integration is useful when the equipment must present regenerated timing to framing logic, mapper circuitry, or payload processing rather than merely buffering data. Designers should verify loop bandwidth, jitter tolerance, acquisition time, and output phase behavior for the designated SDH hierarchy level. The exposed-pad TQFP-EP construction also permits a direct thermal path into the board, although the required pad connection and via pattern must follow the package drawing.

ATM Network Interface Timing

The SY87700LHI is suitable for ATM network-interface timing because its manufacturer-derived product description explicitly identifies ATM applications. The IC recovers timing from 32Mbps to 175Mbps NRZ streams and supports both clock generation and clock-and-data recovery, which suits ATM physical-layer blocks that need a stable timing reference downstream of the line receiver. The single-output configuration should be matched carefully against the intended recovered-clock and recovered-data routing architecture. Before schematic release, engineers must confirm output multiplexing, reference-clock requirements, PLL configuration, and interface voltages in the manufacturer datasheet. Board planning should reserve the complete 32-pin TQFP-EP footprint and place decoupling close to the supply pins to minimize supply-induced timing disturbance.

Ethernet Backplane Timing

The SY87700LHI can be considered for legacy or proprietary Ethernet backplane blocks that use PECL and operate within the verified 32Mbps-to-175Mbps range. Its clock-recovery function removes timing distortion from the received serial stream, while the PLL-based generation path can support related synchronization functions. This makes the device more specialized than a generic Ethernet PHY and requires the system architect to confirm that the electrical interface, recovered-data format, and clock architecture are compatible. Exact jitter, latency, input sensitivity, and reference-clock requirements were not included in the supplied verified extracts. They should be reviewed in the current Microchip Technology datasheet before qualification. Any replacement design must preserve the original 32-pin TQFP-EP land pattern and tested high-speed routing topology.

High-Speed Network Card Timing

The SY87700LHI can serve the timing-recovery section of a high-speed network card handling NRZ links between 32Mbps and 175Mbps. Integrating recovery and clock generation into one 3.3V device can simplify synchronization partitioning while reducing the number of separate ICs on the line interface. The 7x7 mm, 32-pin TQFP-EP package is suitable for dense communications boards, and its exposed-pad construction provides a practical thermal path when continuous recovery operation is required. Designers should still account for PECL supply requirements, input termination, trace length, output loading, and separation between clock and data paths. The verified data does not include power dissipation or junction-temperature limits, so thermal sizing requires the manufacturer datasheet and a calculation based on actual supply and interface activity.

Industrial Communication Equipment

The SY87700LHI is suitable for industrial communication equipment that must recover deterministic timing from a noisy or degraded high-speed NRZ stream. Its verified industrial temperature range of -40°C to +85°C supports use in temperature-controlled industrial networking, test, and transport systems. The device can provide recovered timing and a generated clock from the same package, which helps synchronize downstream digital blocks without relying on an external oscillator-based timing tree. However, the PECL interface and legacy 3.3V architecture require careful grounding and impedance control. Engineers should confirm the device's exact jitter tolerance, lock behavior, supply tolerances, and absolute maximum ratings before using it in new designs. Any upgrade should be treated as a pin-level and timing-performance qualification project rather than a simple marketplace substitution.