Ultra-low jitter fanout buffers with unique fail safe I/O protection

Micrel Inc. has added two new fanout buffers to its unique, patent-pending Fail Safe Input (FSI) family. The SY89467/8U are high-speed, fully differential LVPECL and LVDS buffers with a fanout of 20, and a 2:1 MUX input targeted at hot swap applications.

The SY89467U and SY89468U, along with the rest of Micrel’s FSI MUX and buffer family, are optimized to prevent unwanted oscillations and maintain output stability when an input signal’s swing collapses or disappears. Unlike existing LVPECL or LVDS buffers currently on the market, Micrel’s FSI family prevents a metastable output condition when the input signal is removed or the amplitude fails. In addition, the 3-pin internal input termination simplifies designs and interfaces to any differential signal, AC- or DC-coupled, without any level shifting or termination resistor networks in the signal path.

To further improve the jitter performance, a superior, patented MUX input crosstalk isolation design has been implemented that reduces crosstalk by up to 70 percent. AC performance is guaranteed from DC through 1.5GHz, with rise and fall times less than 110ps for LVDS and LVPECL outputs.

Jitter performance is guaranteed to be less than 10psp-p over temperature and voltage. The product family guarantees operation over the full industrial temperature range (-40C to +85C) and supply voltage operation from 2.5V to 3.3V. All solutions are available in MLF packaging, which features low inductance and capacitance, making the SY89467/8 ideal for today’s high-speed, low jitter designs.