SM802104 ClockWorks Fibre Channel (106.25MHz, 212.5MHz), Ultra-Low Jitter, LVPECL Frequency Synthesizer General Description Features The SM802104 is a member of the ClockWorks family of Generates one or two LVPECL clock outputs at devices from Micrel and provides an extremely low-noise 106.25MHz or 212.5MHz timing solution for Fibre Channel clock signals. It is based 2.5V or 3.3V operating range upon a unique, patented RotaryWave architecture that Typical phase jitter 106.25MHz provides very low phase noise. (637kHz to 10MHz): 200fs The device operates from a 3.3V or 2.5V power supply Industrial temperature range and synthesizes LVPECL output clocks at 106.25MHz or Green, RoHS, and PFOS compliant 212.5MHz. There are normally two clock outputs, but one output can be achieved by powering down the second Available in 24-pin 4mm 4mm QFN package output with the OE pin. The SM802104 accepts a 26.5625MHz crystal or LVCMOS reference clock. Applications Data sheets and support documentation can be found on Fibre Channel Micrels web site at: www.micrel.com. Storage Networking (SAN, NAS) Block Diagram ClockWorks is a trademark of Micrel, Inc RotaryWave is a registered trademark of Multigig, Inc. Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. SM802104 Ordering Information (1) Part Number Marking Shipping Junction Temperature Range Package SM802104UMG 802104 Tube -40C to +85C 24-Pin QFN SM802104UMGR 802104 Tape and Reel 24-Pin QFN -40C to +85C Note: 1. Devices are Green, RoHS, and PFOS compliant. Pin Configuration 24-Pin QFN (code) (Top View) Pin Description Pin Number Pin Name Pin Type Pin Level Pin Function Differential Clock Output from Bank 1 19, 20 /Q1, Q1 O, (DIF) LVPECL 106.25MHz or 212.5MHz Differential Clock Output from Bank 2 22, 23 /Q2, Q2 O, (DIF) LVPECL 106.25MHz or 212.5MHz 24 VDDO2 PWR Power Supply for Output Bank 2 2 VSSO2 PWR Power Supply Ground for Output Bank 2 PLL Bypass, Selects Output Source 0 = Normal PLL Operation 3 PLL BYPASS I, (SE) LVCMOS 1 = Output from Input Reference Clock or Crystal 45K pull-down Selects PLL Input Reference Source 4 XTAL SEL I, (SE) LVCMOS 0 = REF IN, 1 = XTAL, 45K pull-up April 2011 M9999-042111-A 2 hbwhelp micrel.com or (408) 955-1690