FEATURES:

? 1 to 10 differential clock distribution

? Optimized for clock distribution in DDR (Double Data Rate)

SDRAM applications requiring improved output crosspoint

voltage

? Operating frequency: 60MHz to 220MHz

? Very low skew:

– <100ps for PC1600 - PC2700

– <75ps for PC3200

? Very low jitter:

– <75ps for PC1600 - PC2700

– <50ps for PC3200

? 2.5V AVDD and 2.5V VDDQ for PC1600-PC2700

? 2.6V AVDD and 2.6V VDDQ for PC3200

? CMOS control signal input

? Test mode enables buffers while disabling PLL

? Low current power-down mode

? Tolerant of Spread Spectrum input clock

? Available in 48-pin TSSOP, 40-pin VFQFPN, and 56-pin VFBGA

packages

DESCRIPTION:

The CSPT857D is a PLL based clock driver that acts as a zero delay buffer

to distribute one differential clock input pair(CLK, CLK ) to 10 differential output

pairs (Y [0:9],Y [0:9]) and one differential pair of feedback clock output (FBOUT,

FBOUT). External feedback pins (FBIN, FBIN) for synchronization of the

outputs to the input reference is provided. A CMOS Enable/Disable pin is

available for low power disable. When the input frequency falls below

approximately 20MHz, the device will enter power down mode. In this mode,

the receivers are disabled, the PLL is turned off, and the output clock drivers

are tristated, resulting in a current consumption of less than 200μA.

The CSPT857D requires no external components and has been optimised

for very low I/O phase error, skew, and jitter, while maintaining frequency and

duty cycle over the operating voltage and temperature range. The CSPT857D,

designed for use in both module assemblies and system motherboard based

solutions, provides an optimum high-performance clock source.

The CSPT857D is available in Commercial Temperature Range (0°C to

+70°C). See Ordering Information for details