ICS650-07B

Broadcom Clock Source

MD S 650-07B A

Revision 042600

Printed 11/15/00

Integrated Circuit Systems, Inc. ˇ 525 Race Street ˇ San Jose ˇ CA ˇ 95126ˇ(408)295-9800tel ˇ www.icst.com

The ICS650-07B is a low cost, low jitter, high
performance clock synthesizer customized for
Broadcom. Using analog Phase-Locked Loop
(PLL) techniques, the device accepts a 25.00 MHz
clock or fundamental mode crystal input to
produce multiple output clocks of 25.0 MHz, two
125.0 MHz, 133.33 MHz, and a selectable
33.3/66.6 MHz clock. All output clocks are
frequency locked together. The ICS650-07B
outputs all have 0 ppm synthesis error.

Do not use the 125 MHz outputs to drive Gigabit
Ethernet SERDES. Instead, the 25 MHz clock
can be driven into our ICS601 in the X5 mode.
The ICS601 has low enough jitter and phase noise
for all popular SERDES.

Block Diagram

Description

Features

ˇ Packaged in 20 pin narrow (150 mil) SSOP (QSOP)

ˇ 25.00 MHz fundamental crystal or clock input

ˇ Four fixed output clocks of 25 MHz, 133.33 MHz,

and two copies of 125 MHz

ˇ One selectable output clock of 33.3 or 66.6 MHz

ˇ Zero ppm synthesis error in all clocks

ˇ PCI clock switching occurs within 1

ˇ Ideal for Broadcom's BCM5600 chipset

ˇ Full CMOS output swing

ˇ Advanced, low power, sub-micron CMOS process

ˇ 3.0 V to 5.5 V operating voltage

Clock

Buffer/

Crystal

Oscillator

VDD

GND

Clock Synthesis

and Control

Circuitry

133.33 MHz

25.00 MHz
crystal or clock

Output

Buffer

Output

Buffer

125.00 MHz

25.00 MHz

Output

Buffer

125.00 MHz

Output

Buffer

Output

Buffer

PCI CLK

Optional crystal capacitors are shown and may be required for tuning of initial accuracy (determined once per board).

OE (all outputs)

ICS650-07B

Broadcom Clock Source

MD S 650-07B A

Revision 042600

Printed 11/15/00

Integrated Circuit Systems, Inc. ˇ 525 Race Street ˇ San Jose ˇ CA ˇ 95126ˇ(408)295-9800tel ˇ www.icst.com

Pin Descriptions

Key: XI, XO = crystal connections; I = Input; O = Output; P = power supply connection

Pin Assignment

Number

Name

Type

Description

PCI Clock frequency select input. Determines PCI CLK output per table above.

Crystal connection. Connect to 25 MHz crystal or leave unconnected for a clock input.

X1/ICLK

Crystal connection. Connect to 25 MHz fundamental crystal or clock input.

VDD

Connect to +3.3 V or +5 V. Must be same as other VDDs.

Don't Connect. Do not connect anything to this pin.

GND

Connect to ground.

125M

125.0 MHz clock output. Cannot be used for Gigabit Ethernet SERDES.

125M

125.0 MHz clock output. Cannot be used for Gigabit Ethernet SERDES.

Don't Connect. Do not connect anything to this pin.

133M

133.33 MHz clock output.

GND

Connect to ground.

Don't Connect. Do not connect anything to this pin.

GND

Connect to ground.

Output Enable. Tri-states all outputs when low. Internal pull-up.

VDD

Connect to +3.3 V or +5 V. Must be same as other VDDs.

PCICLK

PCI Clock output per table above.

25M

25.0 MHz buffered reference clock output.

VDD

Connect to +3.3 V or +5 V. Must be same as other VDDs.

VDD

Connect to +3.3 V or +5 V. Must be same as other VDDs.

2
3
4

15
14
13

VDD

D C

VDD

20 pin (150 mil) SSOP

5
6
7
8

12
11

133M

VDD

X1/ICLK

25M

VDD

PCICLK

D C
GND

125M

18
17

GND

D C

GND

PCICLK

Pin 1

Pin 17

33.33 MHz

66.66 MHz

PCI CLK Output Select Table

0 = connect directly to GND
1 = connect directly to VDD

ICS650-07B

Broadcom Clock Source

MD S 650-07B A

Revision 042600

Printed 11/15/00

Integrated Circuit Systems, Inc. ˇ 525 Race Street ˇ San Jose ˇ CA ˇ 95126ˇ(408)295-9800tel ˇ www.icst.com

Parameter

Conditions

Minimum

Typical

Maximum

Units

ABSOLUTE MAXIMUM RATINGS (n

note 1)

Supply voltage, VDD

Referenced to GND

Inputs and Clock Outputs

Referenced to GND

-0.5

VDD+0.5

Ambient Operating Temperature

°C

Soldering Temperature

Max of 20 seconds

260

°C

Storage temperature

-65

150

°C

DC CHARACTERISTICS (VDD = 3.3 V unless noted)

Operating Voltage, VDD

5.5

Input High Voltage, VIH, X1 pin only

VDD/2 + 1

VDD/2

Input Low Voltage, VIL, X1 pin only

VDD/2

VDD/2 - 1

Input High Voltage, VIH, PS pin only

VDD-0.5

Input Low Voltage, VIL, PS pin only

0.5

Output High Voltage, VOH

IOH=-12 mA

2.4

Output Low Voltage, VOL

IOL=12 mA

0.4

Output High Voltage, VOH, CMOS level

IOH=-4 mA

VDD-0.4

Operating Supply Current, IDD

No Load

Short Circuit Current

Each output

ą50

Internal pull-up resistor

PS, OE

200

AC CHARACTERISTICS (VDD = 3.3 V

V unless noted)

Input Frequency

25.000

M H z

Output Clock Rise Time

0.8 to 2.0 V

1.5

Output Clock Fall Time

2.0 to 0.8 V

1.5

Output Clock Duty Cycle

At VDD/2

Frequency error

All clocks

ppm

Absolute Jitter, short term

Variation from mean

ą200

Electrical Specifications

Notes:

1. Stresses beyond those listed under Absolute Maximum Ratings could cause permanent damage to the device. Prolonged

exposure to levels above the operating limits but below the Absolute Maximums may affect device reliability.

External Components

The ICS650-07B requires a minimum number of external components for proper operation. Decoupling
capacitors of 0.01ľF should be connected between each VDD and GND, as close to the ICS650-07B as
possible. A series termination resistor of 33

may be used for each clock output. The 25.00 MHz crystal

must be connected as close to the chip as possible. The crystal should be a fundamental mode (do not use
third overtone), parallel resonant. Crystal capacitors should be connected from pins X1 to ground and X2
to ground to optimize the initial accuracy. The value of these capacitors is given by the following equation,
where C

is the crystal load capacitance: Crystal caps (pF) = (C

-6) x 2. So for a crystal with 16 pF load

capacitance, two 20 pF caps should be used.

ICS650-07B

Broadcom Clock Source

MD S 650-07B A

Revision 042600

Printed 11/15/00

Integrated Circuit Systems, Inc. ˇ 525 Race Street ˇ San Jose ˇ CA ˇ 95126ˇ(408)295-9800tel ˇ www.icst.com

While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems, Inc (ICS) assumes no responsibility for either its use or for
the infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use
in normal commercial applications. Any other applications such as those requiring extended temperature range, high reliability, or other extraordinary environmental
requirements are not recommended without additional processing by ICS. ICS reserves the right to change any circuitry or specifications without notice. ICS does not authorize
or warrant any ICS product for use in life support devices or critical medical instruments.

Ordering Information

Part/Order Number

Marking

Shipping packaging

Package

Temperature

ICS650R-07

tubes

20 pin SSOP

0-70°C

ICS650R-07T

ICS650R-07

tape and reel

20 pin SSOP

0-70°C

20 pin SSOP

Inchees

Millim

meters

Symbol

Min

Max

Min

Max

0.053

0.069

1.35

1.75

0.004

0.010

0.10

0.25

0.008

0.012

0.20

0.30

0.007

0.010

0.19

0.25

0.337

0.344

8.56

8.74

.025 BSSC

0.635 B

BSC

0.228

0.244

5.79

6.20

0.150

0.157

3.81

3.99

0.016

0.050

0.41

1.27

INDEX

AREA

Package Outline and Package Dimensions
(

For current dimensional specifications, see JEDEC Publication No. 95.)

Part Number ICS650-07B