ICS557-05A

QUAD DIFFERENTIAL PCI-EXPRESS CLOCK SOURCE

PCIE SSCG

IDT™ / ICS™ QUAD DIFFERENTIAL PCI-EXPRESS CLOCK SOURCE

3

ICS557-05A

REV H 092407

Pin Descriptions

Pin

Pin

Name

Pin

Type

Pin Description

1

VDDXD

Power

Connect to +3.3 V digital supply.

2

S0

Input

Spread spectrum select pin #0. See table above. Internal pull-up resistor.

3

S1

Input

Spread spectrum select pin #1. See table above Internal pull-up resistor.

4

S2

Input

Spread spectrum select pin #2. See table above. Internal pull-up resistor.

5

X1

Input

Crystal connection. Connect to a fundamental mode crystal or clock input.

6

X2

Output

Crystal connection. Connect to a fundamental mode crystal or leave open.

7

PD

Input

Powers down all PLL’s and tri-states outputs when low. Internal pull-up resistor.

8

OE

Input

Provides output on, tri-states output (High = enable outputs; Low = disable outputs).

Internal pull-up resistor.

9

GND

Power

Connect to digital ground.

10

IREF

Output

Precision resistor attached to this pin is connected to the internal current reference.

11

CLKD

Output

Selectable 100/200 MHz spread spectrum differential Compliment output clock D.

12

CLKD

Output

Selectable 100/200 MHz spread spectrum differential True output clock D.

13

CLKC

Output

Selectable 100/200 MHz spread spectrum differential Compliment output clock C.

14

CLKC

Output

Selectable 100/200 MHz spread spectrum differential True output clock C.

15

VDDODA

Power

Connect to +3.3 V analog supply.

16

GND

Power

Connect to analog ground.

17

CLKB

Output

Selectable 100/200 MHz spread spectrum differential Compliment output clock B.

18

CLKB

Output

Selectable 100/200 MHz spread spectrum differential True output clock B.

19

CLKA

Output

Selectable 100/200 MHz spread spectrum differential Compliment output clock A.

20

CLKA

Output

Selectable 100/200 MHz spread spectrum differential True output clock A.