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©2016 Integrated Device Technology, Inc

Revision B June 28, 2016

General Description

The 831752 is a high-performance, differential HCSL clock switch.

The device is designed for the routing of PCIe clock signals in

ATCA/AMC system and is optimized for PCIe Gen 1, Gen 2 and Gen

3. The device has one differential, bi-directional I/O (FCLK) for

connection to ATCA clock sources and to clock receivers through a

connector. The differential clock input CLK is the local clock input

and the HCSL output Q is the local clock output. In the common

clock mode, FCLK serves as an input and is routed to the differential

HCSL output Q. There are two local clock modes. In the local clock

mode 0, CLK is the input, Q is the clock output and FCLK is in

high-impedance state. In the local clock mode 1, CLK is the input

and both Q and FCLK are the outputs of the locally generated PCIe

clock signal. The 831752 is characterized to operate from a 3.3V

power or 2.5V power supply. The 831752 supports the switching of

PCI Express (2.5 Gb/s), Gen 2 (5 Gb/s) and Gen 3 (8 Gb/s) clock

signals.

Features

• Clock switch for PCIe and ATCA/AMC applications

• Supports local and common ATCA/AMC clock modes

• Bi-directional clock I/O FCLK:

- When operating as an output, FCLK is a source-terminated

HCSL signal.

- When operating as an input, FCLK accepts HCSL, LVDS and

LVPECL levels.

• Local clock input (CLK) accepts HCSL, LVDS and LVPECL

differential signals

• Local HCSL clock output (Q)

• Maximum input/output clock frequency: 500MHz

• Maximum input/output data rate: 1000Mb/s (NRZ)

• LVCMOS interface levels for the control inputs

• PCI Express (2.5 Gb/S), Gen 2 (5 Gb/s) and Gen 3 (8 Gb/s) jitter

compliant

• Full 3.3V or 2.5V supply voltage

• Lead-free (RoHS 6) 16-lead TSSOP package

• -40°C to 85°C ambient operating temperature

831752

16-lead TSSOP

4.4mm x 5.0mm x 0.925mm package body

G Package, Top View

Pin Assignment

16

IREF

15

GND

14

VDD

13

Q

12

nQ

11

GND

10

VDD

9

nc

DIR_SEL

1

nOEFCLK

2

VDD

3

FCLK

4

nFCLK

5

GND

6

CLK

7

nCLK

8

Block Diagram

Pulldown

Pullup/Pulldown

Pullup

Pulldown

FCLK

nFCLK

CLK

nCLK

nOEFCLK

DIR_SEL

IREF

1

0

Q

nQ

1=disable

50

50

50

50

22.33

22.33

Clock Switch for ATCA/AMC and PCIe

Applications

831752

Data Sheet