Low phase-noise clock synthesizer includes typical RMS jitter below 500 femtoseconds
Semtech Corporation announced the general availability of the ACS1790T, a new low phase noise clock synthesizer.
The ACS1790T is a tiny device offering frequency selection better than one part-per-billion on a low phase noise platform with typical RMS jitter below 500 femtoseconds.
The new part is suitable for a wide range of demanding applications including 10G Ethernet, Synchronous Ethernet, SONET/SDH, FibreChannel, CDR, software controlled clock generation and other reference clocks. It can be used either as a stand-alone frequency synthesizer or as a companion chip to the ACS9522T ToPSync system synchronization solution, generating a low phase noise local reference clock that is aligned to the system timing recovered by the ACS9522T.
As a standalone frequency synthesizer, the ACS1790T offers outstanding flexibility with a 24-bit fractional feedback divider that generates any output frequency with a resolution of 0.5 parts-per-billion (ppb). This allows synthesis of any output frequency within the range of 10 MHz to 200 MHz on the LVPECL output and 2 KHz to 125 MHz on the LVCMOS output.
The part is packaged in a 4mm x 4mm 24-QFN package. All loop components are on-chip simplifying the circuit board layout and making the total solution footprint ideal for space-constrained applications. The combination of a high fractional resolution with a simple serial interface also makes the ACS1790T ideal for use in software-controlled loops where a translated but disciplined or traceable clock is required.
Key Features of the ACS1790 Frequency Synthesizer
· Very low RMS phase jitter, < 500 fs typical (integrated from 12kHz-20MHz)
· Flexibly generates any frequency within following frequency ranges with 0.5 ppb precision
o LVPECL output: 10 MHz - 200 MHz
o LVCMOS output: 2 KHz – 125 MHz
· Supports 1G/10G Ethernet, SONET/SDH, E1/T1, PCI Express and many other standards
· Pin-strapped start-up modes for 1G / 10G Ethernet frequencies
· Simple serial interface for control and configuration
· 4mm x 4mm 24-QFN package
Pricing and availability
The ACS1790T product (order code: ACS1790IMLTRT) is available in production quantities and is priced at $9.00 each in 10,000-piece lots. Semtech offers comprehensive design assistance, including field- and factory-based support. Data sheets, volume pricing, and delivery quotes, as well as evaluation kits and samples, are available at www.semtech.com/info.