SY55856UHG

Overview

The SY55856UHG is a SuperLite differential two-channel precision CML delay line manufactured by Microchip Technology. It operates within a supply voltage range of 2.3V to 3.6V and supports maximum frequencies exceeding 2.5GHz with a throughput up to 5Gbps. The device provides a total adjustable delay range of ±350ps in 50ps increments, controlled via three digital select pins. It features source-terminated CML outputs optimized for 50Ω loads, delivering a 400mV differential swing. Propagation delay is guaranteed at less than 384ps, with rise/fall times under 120ps. The component is housed in a 32-pin EPAD-TQFP package and functions across an industrial temperature range from -40°C to +85°C.

Feature Summary

• Provides digitally controlled relative delay adjustment between clock and data channels in precise 50ps steps.
• Features fully differential CML inputs and outputs designed for high-speed signal integrity.
• Includes a variable threshold control input (LVL) to accommodate various logic families such as TTL or PECL.

Applications

• Signal de-skewing in high-speed data communication systems
• Pulse alignment in telecom infrastructure
• Digitally controlled delay lines for high-speed backplanes

Procurement Notes

Verify the specific ordering suffix to confirm the package type and lead finish. The 'HG' suffix indicates a Pb-Free variant with NiPdAu finish. Confirm that the procurement channel sources the correct tape and reel quantity if applicable. Ensure the supplier provides valid RoHS compliance documentation matching the specific manufacturing batch.

Selection Notes

Select this component when precise relative timing adjustments are required between differential signals. Ensure the system design accommodates the 2.3V to 3.6V supply range and utilizes appropriate 50Ω source termination for the CML outputs. Verify that the control interface logic levels match the LVL pin configuration requirements.

Part Context

This part belongs to the SuperLite family of high-speed analog and digital crosspoint ICs originally developed by Micrel, which was acquired by Microchip Technology. The series focuses on precision timing and signal routing solutions for telecommunications and networking applications requiring low jitter and fast switching speeds.

Replacement Considerations

Check for updated Microchip datasheets as the original manufacturer notes this part is not recommended for new designs. Evaluate alternative devices from the same family or newer generations that offer equivalent delay ranges and CML specifications while supporting current manufacturing standards.

FAQ

How is the delay direction controlled?

The DELAY_SEL pin determines whether the clock signal is delayed relative to the data signal or vice versa. A logic high delays the clock, while a logic low delays the data.

What is the function of the LVL pin?

The LVL pin sets the voltage threshold for the variable threshold inputs (S0, S1, S2, DELAY_SEL, CINV), allowing the device to interface with different logic families like TTL or PECL.

Can the clock input be inverted?

Yes, the CINV pin allows for optional inversion of the CLK_IN signal, resulting in an inverted CLK_OUT output when driven above the threshold voltage.