
Micrel
General Description
The SY89221U is a 2.5/3.3V precision, high-speed, integrated clock divider and LVPECL fanout buffer capable of handling clocks up to 1.5GHz. Optimized for communications applications, the four independently controlled output banks are phase-matched and can be configured for pass through ÷1, ÷2 or ÷4 divider ratios.
FEATUREs
• Four low-skew LVPECL output banks with
independently programmable ÷1, ÷2 and ÷4 divider
options
• Four output banks, 15 total outputs
• Guaranteed AC performance over temperature and
voltage:
– Accepts a clock frequency up to 1.5GHz
– <1600ps IN-to-OUT propagation delay
– <270ps rise/fall time
– <35 ps within-bank skew
• Fail Safe Input
– Prevents outputs from oscillating
• Ultra-low jitter design:
– <1psRMS random jitter
– <10psPP total jitter (clock)
• Patent-pending input termination and VT pin
accepts DC- and AC-coupled inputs (CML, PECL,
LVDS)
• CMOS/TTL-compatible output enable (EN) and
divider select control
• 2.5V ±5% or 3.3V ±10% power supply
• –40°C to +85°C temperature range
• Available in 64-pin TQFP
APPLICATIONs
• All SONET/SDH applications
• All Fibre Channel applications
• All Gigabit Ethernet applications