September 2006

PCS2I9942C

rev 0.3

Notice: The information in this document is subject to change without notice.

PulseCore Semiconductor Corporation

1715 S. Bascom Ave Suite 200, Campbell, CA 95008

• Tel: 408-879-9077 • Fax: 408-879-9018

www.pulsecoresemi.com

Low Voltage 1:18 Clock Distribution Chip

Features

•

LVCMOS/LVTTL Clock Input

•

2.5V

LVCMOS

Outputs

for

PentiumII

TM

Microprocessor Support

•

150pS Maximum Targeted Output–to–Output

Skew

•

Maximum Output Frequency of 250MHz @ 3.3

•

32–Lead TQFP and LQFP Packaging

•

Single 3.3V or 2.5V Supply.

•

Pin and Function compatible to MPC942C

.

Functional Description

The PCS2I9942C is a 1:18 low voltage clock distribution

chip with 2.5V or 3.3V LVCMOS output capabilities. The

device is offered in two versions; the PCS2I9942C hPcs an

LVCMOS input clock while the PCS2I9942P hPcs an

LVPECL input clock. The 18 outputs are 2.5V or 3.3V

LVCMOS compatible and feature the drive strength to drive

50Ω series or parallel terminated transmission lines. With

output–to–output skews of 200pS, the PCS2I9942C is ideal

Pcs a clock distribution chip for the most demanding of

synchronous systems. The 2.5V outputs also make the

device ideal for supplying clocks for a high performance

Pentium II

With a low output impedance (≈12Ω), in both the HIGH and

LOW logic states, the output buffers of the PCS2I9942C

are ideal for driving series terminated transmission lines.

With an output impedance of 12Ω, the PCS2I9942C can

drive two series terminated transmission lines from each

output. This capability gives the PCS2I9942C an effective

fanout of 1:36. The PCS2I9942C provides enough copies

of low skew clocks for most high performance synchronous

systems.

The LVCMOS/LVTTL input of the PCS2I9942C provides a

more standard LVCMOS interface. The OE pins will place

the outputs into a high impedance state. The OE pin hPcs

an internal pullup resistor.

pins require either 2.5V or 3.3V. The 32–lead TQFP and

LQFP package is chosen to optimize performance, board

space and cost of the device. The 32–lead TQFP hPcs a

7x7mm

*Pentium II is a trademark of Intel Corporation