SY89809LTH-TR

Clock Buffers, Drivers Overview

The SY89809LTH-TR is a high-performance bus clock driver manufactured by Microchip Technology, housed in a 32-pin TQFP package. It provides nine differential HSTL output pairs and supports both HSTL and LVPECL inputs selected via the CLK_SEL pin. The device operates with a 3.3V core supply (VCCI: 3.0V to 3.6V) and an 1.8V output supply (VCCO: 1.6V to 2.0V). Key electrical parameters include a maximum operating frequency of 500MHz, a maximum part-to-part skew of 200ps, and a maximum pin-to-pin skew of 50ps. The synchronous Output Enable (OE) prevents runt clock pulses.

Clock Buffers, Drivers Feature Summary

• Features a 1:9 fanout ratio with nine differential HSTL output pairs driving 50Ω loads to ground without offset voltage.
• Supports dual input logic levels (HSTL or LVPECL) selectable via the CLK_SEL pin.
• Provides low skew performance with a maximum pin-to-pin skew of 50ps and part-to-part skew of 200ps.
• Includes a synchronous Output Enable (OE) mechanism that disables outputs only during the LOW state to prevent glitches.

Clock Buffers, Drivers Applications

• High-performance PCs
• Workstations
• Parallel processor-based systems
• Other high-performance computing applications
• Communications equipment

Clock Buffers, Drivers Procurement Notes

Verify component authenticity through authorized channels as the datasheet indicates the product is not recommended for new designs. Confirm lead finish specifications, as the TH suffix denotes a Pb-Free package with NiPdAu finish. Ensure compliance with RoHS standards and check moisture sensitivity level (MSL 3) requirements for surface mount assembly processes.

Clock Buffers, Drivers Selection Notes

Select this component when a large number of precisely aligned clock signals are required from a single source. Ensure the design accommodates separate 3.3V and 1.8V power supplies for the core and output buffers respectively. Verify that the input signal matches either HSTL or LVPECL standards, as the device does not support simultaneous operation of both input types.

Clock Buffers, Drivers Part Context

The SY89809L belongs to the Precision Edge series of clock drivers originally developed by Micrel, which was subsequently acquired by Microchip Technology. The device is designed to replace standard clock distribution solutions requiring ultra-low skew across multiple outputs. The -TR suffix indicates the component is supplied in tape and reel packaging for automated surface-mount assembly.

Clock Buffers, Drivers Replacement Considerations

The datasheet explicitly states the SY89809L is not recommended for new designs. Engineers should evaluate newer generation clock buffer families from Microchip or other manufacturers that offer similar 1:9 fanout ratios with updated process technologies and improved power efficiency.

Clock Buffers, Drivers FAQ

How is the input source selected between HSTL and LVPECL?

The input source is selected via the CLK_SEL pin. When CLK_SEL is LOW, the HSTL_CLK inputs are active. When CLK_SEL is HIGH, the LVPECL_CLK inputs are active.

What is the function of the synchronous Output Enable (OE)?

The OE signal synchronizes the enabling and disabling of outputs with the low level of the clock signal. This ensures outputs are disabled only when already in the LOW state, preventing the generation of runt clock pulses.

What are the power supply requirements for the SY89809L?

The device requires two distinct power supplies: VCCI (Core Power) must be between 3.0V and 3.6V, and VCCO (Output Buffer Power) must be between 1.6V and 2.0V.