Micrel, Inc.
3.3V, 500MHz 1:22 DIFFERENTIAL HSTL (1.5V) FANOUT BUFFER/TRANSLATOR
Precision Edge®
Precision ESdY8g9e82®...
Micrel, Inc.
3.3V, 500MHz 1:22 DIFFERENTIAL HSTL (1.5V) FANOUT BUFFER/TRANSLATOR
Precision Edge®
Precision ESdY8g9e82®3L SY89823L
FEATURES
s 22 differential HSTL (low-
voltage swing) output pairs s HSTL outputs drive 50Ω to ground with no offset
voltage s 3.3V core supply, 1.8V output supply for reduced
power s LVPECL and HSTL inputs s Low part-to-part skew (200ps max.) s Low pin-to-pin skew (50ps max.) s Triple-buffered output enable (OE) s –40°C to +85°C temperature range s Available in a 64-pin EPAD-TQFP
APPLICATIONS
s High-performance PCs s Workstations s Parallel processor-based systems s Other high-performance computing s Communications
Precision Edge®
DESCRIPTION
The SY89823L is a high-performance bus clock driver with 22 differential High-Speed Transceiver Logic (HSTL), 1.5V compatible output pairs. The device is designed for use in low-
voltage (3.3V/ 1.8V) applications that require a large number of outputs to drive precisely aligned, ultra-low skew signals to their destination. The input is multiplexed from either HSTL or Low-
Voltage PositiveEmitter-Coupled Logic (LVPECL) by the CLK_SEL pin.
The Output Enable (OE) is synchronous and triple-buffered so that the outputs will only be enabled/disabled when they are already in the LOW state. This avoids any potential of generating a runt clock pulse when the device is enabled/disabled, as can occur with an asynchronous control. The triple-buffering feature provides a threeclock delay from the time the OE input is ass...