Microchip | SY89841UMG-TR

The SY89841UMG TR is a low jitter LVDS, 2:1 input multiplexer (MUX) optimized for redundant source switch over applications. Unlike standard multiplexers, the SY89841U 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 100 mV).

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 100 mV (200 mVpp) without any level shifting or termination resistor networks in the signal path. The outputs are 350 mV, LVDS with fast rise/fall times guaranteed to be less than 150 ps. The SY89841U operates from a 2.5 V ±5% supply and is guaranteed over the full industrial temperature range of –40°C to +85°C. The SY89841U is part of Micrel’s high-speed, Precision Edge® product line.

Key Features:

• Selects between two sources, and provides a glitch-free, stable LVDS output.
• Guaranteed AC performance over temperature and supply voltage:
• wide operating frequency: 1 kHz to >1.5 GHz.
  • <870 ps In-to-Out tpd.
  • <150 ps tr/tf.
• Unique patent-pending input isolation design minimizes crosstalk.
• Fail-safe input prevents oscillations..
• Ultra-low jitter design:
  • <1 psrms random jitter.
  • <1 psrms cycle-to-cycle jitter.
  • <10 pspp total jitter (clock).
  • <0.7 psrms MUX crosstalk induced jitter.
• Unique patent-pending input termination and VT pin accepts DC-coupled and AC-coupled inputs (CML,
• ECL, LVDS).
• 350 mV LVDS output swing.
• 2.5 V +5% power supply.
• –40°C to +85°C industrial temperature range.
• Available in 16-pin (3 mm x 3 mm) MLF™ package.

Applications:

• Redundant clock switchover.
• Fail-safe clock protection.