CDCVF857RTBT

Clock Generators, PLLs, Frequency Synthesizers Overview

The CDCVF857RTBT is a discontinued 2.5-V phase-locked-loop clock driver manufactured by Texas Instruments. It functions as a zero-delay buffer, distributing a differential clock input pair to ten differential pairs of clock outputs and one differential feedback pair. The device operates within a frequency range of 60 MHz to 220 MHz. Key electrical characteristics include cycle-cycle jitter of ±35 ps, period jitter of ±30 ps, and static phase offset of ±50 ps. It utilizes SSTL2 signaling standards and requires dual supplies: AVDD for the PLL and VDDQ for I/O. The component is housed in a 40-pin MLF (VQFN) package with an exposed pad.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Zero-delay buffer architecture that aligns output clock phases directly with the reference input.
• Supports spread-spectrum clocking capabilities to reduce electromagnetic interference.
• Integrates low-power mode functionality that disables outputs and shuts down the PLL when no input signal is detected or during power-down states.

Clock Generators, PLLs, Frequency Synthesizers Applications

• DDR memory modules supporting PC1600 through PC3200 specifications
• High-speed digital systems requiring precise clock distribution
• Spread-spectrum clock generation for EMI reduction

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the obsolete status of this part number before initiating any procurement actions. Confirm availability through authorized distributors or secondary market suppliers, as production has ceased. Ensure that the specific package variant matches design requirements, as lead times may vary significantly for remaining stock.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this component only if the application specifically requires the 40-pin MLF package form factor and SSTL2 interface compatibility. Evaluate alternative active devices from the same family, such as the RHAT or DGG variants, which offer different packaging options while maintaining identical electrical performance profiles.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This device belongs to the CDCVF857 series of high-performance clock drivers designed for DDR memory applications. It shares functional similarities with other members of the family but is distinguished by its specific 40-pin MLF packaging configuration. The RTB suffix indicates the specific physical package type used in this discontinued iteration.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

CDCVF857RHAT

Clock Generators, PLLs, Frequency Synthesizers FAQ

What is the stabilization time required for the PLL to achieve phase lock?

The stabilization time for the integrated PLL circuit to obtain phase lock is 10 microseconds following power-up.

How does the device behave when the PWRDWN pin is set low?

When the PWRDWN pin is low, all outputs switch to a high-impedance state, and the PLL is shut down to enter a low-power mode.

What are the recommended supply voltage ranges for operation?

The device operates from dual supplies: AVDD typically at 2.5 V and VDDQ ranging from 2.3 V to 2.7 V depending on the specific speed grade.