SY89845U Datasheet | Micrel Semiconductor

Precision CML Runt Pulse Eliminator 2:1 MUX with 1:2 Fanout and Internal Termination General Description The SY89845U is a low jitter CML, 2:1 differential input multiplexer (MUX) optimized for redundant source switchover applications. Unlike standard multiplexers, the SY89845U unique 2:1 Runt Pulse Eliminator (RPE) MUX prevents any short cycles or “runt” pulses during switchover. In addition, a unique Fail-Safe Input protection prevents metastable conditions when the selected input clock fails to a DC voltage (voltage between the pins of the differential input drops below 100m V). The differential input includes Micrel’s unique, 3-pin input termination architecture that allows customers to interface to any differential signal (AC- or DCcoupled) as small as 100m V (200m VPP) without any level shifting or termination resistor networks in the signal path. The outputs are 400m V CML with fast rise/fall times guaranteed to be less than 80ps. The SY89845U operates from a 2.5V ±5% or 3.3V ±10% supply and is guaranteed over the full industrial temperature range of - 40°C to +85°C. The SY89845U is part of Micrel’s high-speed, Precision Edge® product line. All support documentation can be found on Micrel’s web site at: .micrel.. Features Precision Edge® - Selects between two sources, and provides a glitchfree, stable CML output - Guaranteed AC performance over temperature and supply voltage: - Wide operating frequency: 1k Hz to >1.5GHz - < 840ps In-to-Out tpd - < 80ps tr/tf - Unique, patent-pending input isolation design minimizes crosstalk - Fail-Safe Input prevents oscillations - Ultra-low jitter design: - <1ps RMS random jitter - <1ps RMS cycle-to-cycle jitter - <10ps PP total jitter (clock) - <0.7ps RMS MUX crosstalk induced jitter - Unique patented input termination and VT pin accepts DC- and AC-coupled inputs (CML, PECL, LVDS) - 400m V CML output swing - 2.5V ±5% or 3.3V ±10% supply voltage - -40°C to +85°C industrial temperature range - Available in 24-pin...