SM844256 10 Gigabit Ethernet and SONET, 6 Output, Ultra-Low Jitter LVDS Frequency Synthesizer General Description Features The SM844256 provides a low-noise timing solution for Generates six LVDS outputs high speed, high accuracy synthesis of clock signals. 2.5V or 3.3V operating range Common applications include SONET, Gigabit Ethernet, Typical phase jitter 125MHz 10 Gigabit Ethernet, and similar networking standards. It (1.875MHz to 20MHz): 80 fs (typical) 3.3V includes a power reduction methodology, along with a TM 75MHz to 625MHz output frequencies patented RotaryWave architecture that provides a very stable clock with very low noise. Industrial temperature range Power supplies of either 3.3V or 2.5V are supported, with Green, RoHS, and PFOS compliant superior jitter and phase noise performance. The device Available in 24-pin TSSOP EPAD synthesizes different low noise LVDS output frequencies Operating supply modes: such as 125MHz, 156.25MHz, 312.5MHz, and 625MHz for Core/Output Ethernet applications 77.76MHz, 155.52MHz, 311.04MHz, 3.3V/3.3V, 3.3V/2.5V, 2.5V/2.5V and 622.08MHz for SONET applications. The crystal reference frequencies used include 25MHz and 19.44Mhz for Ethernet and SONET applications, respectively. Applications The SM844256 is an excellent replacement for IDT Femto- SONET clocks, with improved accuracy, power consumption, waveform integrity, and jitter. Gigabit Ethernet Data sheets and support documentation can be found on 10-Gigabit Ethernet Micrels web site at: www.micrel.com. Infiniband Block Diagram Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. SM844256 (1, 2) Ordering Information Part Number Marking Shipping Junction Temperature Range Package SM844256KA 844256 Tube, Tape & Reel 40 to +85C 24-Pin TSSOP EPAD Notes: 1. Devices are Green, RoHS, and PFOS Compliant. 2. Lead finish is 100% matte tin. Pin Configuration 24-Pin TSSOP EPAD (Top View) July 2010 2 M9999-072110-B