SY89855U Precision Low Power Differential LVPECL 4:1 MUX with 1:2 Fanout and Internal Termination General Description The SY89855U is a 2.5V/3.3V precision, high-speed, Precision Edge 4:1 differential multiplexer with 100K LVPECL (800mV) Features compatible outputs, capable of handling clocks up to 2.5GHz and data streams up to 2.5Gbps. In addition, a Select 1 of 4 differential inputs 1:2 fanout buffer provides two copies of the selected Provides two copies of the selected input inputs. Low power 260mW (V = 2.5V) CC The differential input includes Micrels unique, 3-pin Guaranteed AC performance over temperature and input termination architecture that allows customers to voltage: interface to any differential signal (AC- or DC-coupled) DC-to->2.5Gbps data rate throughput as small as 100mV without any level shifting or <410ps In-to-Q t pd termination resistor networks in the signal path. The <180ps t / t times r f result is a clean, stub-free, low-jitter interface solution. The outputs are 800mV LVPECL, (100K temperature Ultra low-jitter design: compensated) with fast rise/fall times guaranteed to be <10ps total jitter (clock) PP less than 180ps. <1ps random jitter RMS The SY89855U operates from a 2.5V 5% supply or a <10ps deterministic jitter PP 3.3V 10% supply and is guaranteed over the full <0.7ps crosstalk-induced jitter RMS industrial temperature range of 40C to +85C. For Unique, patent-pending input design minimizes applications that require higher performance, consider crosstalk the SY58029U. The SY89855U is part of Micrels high- Accepts an input signal as low as 100mV speed, Precision Edge product line. Unique patented input termination and VT pin All support documentation can be found on Micrels web accepts DC- and AC-coupled inputs (CML, LVPECL, site at www.micrel.com. LVDS) 800mV 100K LVPECL output swing Typical Performance Power supply 2.5V 5% or 3.3V 10% 40C to +85C temperature range Available in 32-pin (5mm x 5mm) QFN package Applications Redundant clock and/or data distribution All SONET/OC-3 to OC-48 clock/data distribution Loopback All Fibre Channel applications All GigE applications Markets LAN/WAN communication Enterprise servers ATE Test and measurement Precision Edge is a registered trademark of Micrel, Inc. Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. SY89855U Functional Block Diagram Truth Table SEL1 SEL0 Q 0 0 IN0 Input Select 0 1 IN1 Input Select 1 0 IN2 Input Select 1 1 IN3 Input Select 2 M9999-082907-C August 2007 hbwhelp micrel.com or (408) 955-1690