843034AY

www.icst.com/products/hiperclocks.html

REV. A JULY 25, 2005

1

Integrated

Circuit

Systems, Inc.

ICS843034

PRELIMINARY

The ICS843034 is a general purpose, low phase

noise LVPECL synthesizer which can generate

frequencies for a wide variety of applications. The

ICS843034 has a 4:1 input Multiplexer from which

the following inputs can be selected: 1 differential

input, 1 single-ended input, or two crystal

oscillators, thus making the device ideal for frequency

translation or frequency generation. Each differential LVPECL

output pair has an output divider which can be independently

set so that two different frequencies can be generated.

Additionally, each LVPECL output pair has a dedicated power

supply pin so the outputs can run at 3.3V or 2.5V. The

ICS843034 also supplies a buffered copy of the reference

clock or crystal frequency on the single-ended REF_CLK pin

which can be enabled or disabled (disabled by default). The

output frequency can be programmed using either a serial or

parallel programming interface.

The phase jitter of the ICS843034 is less than 1ps rms, making

it suitable for use in Fibre Channel, SONET, and Ethernet

applications.

Example applications include systems which must support

both FEC and non FEC rates. In 10Gb Fibre Channel, for

example, you can use a 25.5MHz crystal to generate a

159.375MHz reference clock, and then switch to a 20.544MHz

crystal to generate 164.355MHz for 66/64 FEC. Other

applications could include suppor ting both Ether net

frequencies and SONET frequencies in an application. When

Ethernet frequencies are needed, a 25MHz crystal can be

used and when SONET frequencies are needed, the input

MUX can be switched to select a 38.88MHz Crystal.

• Dual differential 3.3V LVPECL outputs which can be set

independently for either 3.3V or 2.5V

• 4:1 Input Mux:

1 differential input

1 single-ended input

2 crystal oscillator interfaces

• CLK, nCLK pair can accept the following differential

input levels: LVPECL, LVDS, LVHSTL, HCSL, SSTL

• TEST_CLK accepts LVCMOS or LVTTL input levels

• Output frequency range: 35MHz to 750MHz

• Crystal input frequency range: 12MHz to 40MHz

• VCO range: 560MHz to 750MHz

• Parallel or serial interface for programming feedback

divider and output dividers

• RMS phase jitter at 333.33MHz, using a 22.222MHz

crystal (12kHz to 20MHz): 0.80ps (typical)

• Supply voltage modes:

LVPECL outputs (core/outputs):

3.3V/3.3V

3.3V/2.5V

REF_CLK output (core/outputs):

3.3V/3.3V

• 0°C to 70°C ambient operating temperature

• Industrial temperature available upon request

• Available in both, Standard and RoHS/Lead-Free compli-

ant packages

HiPerClockS™

ICS

48 47 46 45 44 43 42 41 40 39 38 37

13 14 15 16 17 18 19 20 21 22 23 24

1

2

3

4

5

6

7

8

9

10

11

12

36

35

34

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32

31

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25

M8

NB0

NB1

NB2

OE_REF

OE_A

OE_B

NA0

NA1

NA2

XTAL_OUT1

XTAL_IN1

XTAL_OUT0

XTAL_IN0

TEST_CLK

SEL1

SEL0

S_LOAD

S_DATA

S_CLOCK

MR

ICS843034

48-Pin LQFP

7mm x 7mm x 1.4mm

package body

Y Package

Top View

The Preliminary Information presented herein represents a product in prototyping or pre-production. The noted characteristics are based on initial

product characterization. Integrated Circuit Systems, Incorporated (ICS) reserves the right to change any circuitry or specifications without notice.