8752CYI

REV. C JULY 30, 2010

1

ICS8752I

LOW SKEW, 1-TO-8

LVCMOS CLOCK MULTIPLIER/ZERO DELAY BUFFER

BLOCK DIAGRAM

PIN ASSIGNMENT

32 31 30 29 28 27 26 25

9

10 11 12 13 14 15 16

1

2

3

4

5

6

7

8

24

23

22

21

20

19

18

17

GND

QB1

QB0

VDDO

VDDO

QA3

QA2

GND

DIV_SELB0

DIV_SELB1

DIV_SELA0

DIV_SELA1

MR/nOE

CLK0

GND

FB_IN

ICS8752I

32-Lead LQFP

7mm x 7mm x 1.4mm package body

Y package

Top View

÷2

÷4

÷6

÷8

÷12

PLL

PHASE

DETECTOR

PLL_SEL

FB_IN

CLK0

CLK1

CLK_SEL

DIV_SELA1

DIV_SELA0

DIV_SELB1

DIV_SELB0

MR/nOE

QA0

QA1

QA2

QA3

QB0

QB1

QB2

QB3

0

1

1

0

00

01

10

11

00

01

10

11

VCO

GENERAL DESCRIPTION

The ICS8752I is a low voltage, low skew LVCMOS clock

generator. With output

up to 240MHz, the ICS8752I is

targeted for high performance clock applications. Along with

a fully integrated PLL, the ICS8752I contains frequency

configurable outputs and an external feedback input for

regenerating clocks with “zero delay”.

Dual clock inputs, CLK0 and CLK1, support redundant clock

applications. The CLK_SEL input determines which reference

clock is used. The output divider values of Bank A and B are

controlled by the DIV_SELA0:1, and DIV_SELB0:1, respectively.

For test and system debug purposes, the PLL_SEL input

allows the PLL to be bypassed. When HIGH, the MR/nOE

input resets the internal dividers and forces the outputs to

the high impedance state.

The low impedance LVCMOS outputs of the ICS8752I are

designed to drive ter minated transmission lines. The

effective fanout of each output can be doubled by

utilizing the ability of each output to drive two series

terminated transmission lines.

FEATURES

• Fully integrated PLL

• 8 LVCMOS outputs, 7Ω typical output impedance

• Selectable LVCMOS CLK0 or CLK1 inputs for

redundant clock applications

• Input/Output frequency range: 18.33MHz to 240MHz

at V

CC = 3.3V ± 5%

• VCO range: 220MHz to 480MHz

• External feedback for “zero delay” clock regeneration

• Cycle-to-cycle jitter: 75ps (maximum),

(all outputs are the same frequency)

• Output skew: 100ps (maximum)

• Bank skew: 55ps (maximum)

• Full 3.3V or 2.5V supply voltage

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

• Lead-Free package fully RoHS compliant