843003AG

www.icst.com/products/hiperclocks.html

REV. A JULY 27, 2004

1

Integrated

Circuit

Systems, Inc.

ICS843003

The ICS843003 is a 3 differential output LVPECL

Synthesizer designed to generate Ethernet refer-

ence clock frequencies and is a member of the

HiPerClocks™ family of high performance clock

solutions from ICS. Using a 31.25MHz or

26.041666MHz, 18pF parallel resonant crystal, the following fre-

quencies can be generated based on the settings of 4 frequency

select pins (DIV_SEL[A1:A0], DIV_SEL[B1:B0]): 625MHz,

312.5MHz, 156.25MHz, and 125MHz.The 843003 has 2 output

banks, Bank A with 1 differential LVPECL output pair and Bank

B with 2 differential LVPECL output pairs.

The two banks have their own dedicated frequency select pins

and can be independently set for the frequencies mentioned

above.The ICS843003 uses ICS’3rd generation low phase noise

VCO technology and can achieve 1ps or lower typical rms phase

jitter, easily meeting Ethernet jitter requirements.The ICS843003

is packaged in a small 24-pin TSSOP package.

• Three 3.3V LVPECL outputs on two banks, A Bank with

one LVPECL pair and B Bank with 2 LVPECL output pairs

• Using a 31.25MHz or 26.041666 crystal, the two output

banks can be independently set for 625MHz, 312.5MHz,

156.25MHz or 125MHz

• Selectable crystal oscillator interface or LVCMOS/LVTTL

single-ended input

• VCO range: 560MHz to 700MHz

• RMS phase jitter @ 156.25MHz (1.875MHz - 20MHz):

0.51ps (typical)

• RMS phase noise at 156.25MHz

Phase noise:

Offset

Noise Power

100Hz ............... -96.8 dBc/Hz

1KHz .............. -119.1 dBc/Hz

10KHz .............. -126.4 dBc/Hz

100KHz .............. -127.0 dBc/Hz

• Full 3.3V supply mode

• 0°C to 70°C ambient operating temperature

• Industrial temperature available upon request

HiPerClockS™

ICS

0

1

0

1

Phase

Detector

VCO

625MHz

0 = ÷20 (default)

1 = ÷24

0 0

÷1

0 1

1 0

÷4

1 1

÷5

0 0

÷1

0 1

÷2

1 0

1 1

÷5

FB_DIV

OSC

OEA

DIV_SELA[1:0]

VCO_SEL

TEST_CLK

XTAL_IN

XTAL_OUT

XTAL_SEL

FB_DIV

DIV_SELB[1:0]

MR

OEB

QA0

nQA0

QB0

nQB0

QB1

nQB1

Pulldown

Pulldown

Pullup

Pullup

Pullup

Pullup

ICS843003

24-Lead TSSOP

4.40mm x 7.8mm x 0.92mm

package body

G Package

Top View

DIV_SELB0

VCO_SEL

MR

QA0

nQA0

OEB

OEA

FB_DIV

DIV_SELA0

1

2

3

4

5

6

7

8

9

10

11

12

DIV_SELB1

QB0

nQB0

QB1

nQB1

XTAL_SEL

TEST_CLK

XTAL_IN

XTAL_OUT

DIV_SELA1

24

23

22

21

20

19

18

17

16

15

14

13

Pulldown