DATASHEET
SPREAD SPECTRUM CLOCK GENERATOR ICS7152A
IDT™ / ICS™
SPREAD SPECTRUM CLOCK GENERATOR 1
ICS7152A REV B 011008
Description
The ICS7152A-02 and -11 are cloc k generators for EMI
(Electromagnetic Inter ference) reduction (see below for
frequency ranges and multiplier ratios). Spectral peaks are
attenuated by modulating the system clock frequency.
Down or center spread profiles are selectable. Down
spread will not exceed the maximum frequency of an
unspread clock, and center spread does not change the
average operating frequency of the system
IDT offers many other clocks for computers and computer
peripherals . Consult IDT when y ou need to remov e crystals
and oscillators from your board.
Features
•Operating voltage of 3.3 V ±0.3 V
•Packaged in 8-pin SOIC
•Input frequency range of 16.6 to 134.0 MHz
•Output frequency range of 16.6 to 134.0 MHz
•Provides a spre ad spect rum cloc k out p ut ( ±0. 5%, ±1. 5%
center spread; -1.0%, -3.0% down spread)
•Low cycle-to-cycle jitter - less than 100 ps
•Advanced, low-power CMOS process
•Industrial and commercial temperature ranges
•Availab le in Pb (lead) free package
•Pin compatible with Fujitsu MB88152-102 and -111
Block Diagram
Product Lineup
Product Input Frequency Range Modulation Type Modulation Enable Pin
ICS7152AM -0 2 , IC S7 15 2AMI-02 40.0 MHz to 134.0 MHz Down spread Yes
ICS7152AM-11, ICS7152AMI-11 16.6 MHz to 67.0 MHz Center spread
PLL Clock
Synthesis
and Spread
Spectrum
Circuitry
SEL
FREQ
CKOUT
GND
VDD
Clock Buffer/
Crystal
Ocsillator
XIN
XOUT
External caps required with crystal for
accurate tuning of the clock
XENS
ICS7152A
SPREAD SPECTRUM CLOCK GENERATOR SSCG
IDT™ / ICS™
SPREAD SPECTRUM CLOCK GENERATOR 2
ICS7152A REV B 011008
Pin Assignment
Modulation Enable Select Table
Spread Direction and Percentage
Select Table
Frequency Select Table
Pin Descriptions
XENS
Pin 8 Modulation
0 Modulation
1 No modulation
XENS
XOUT
GND
FREQ
SEL CKOUT
VDD
XIN 1
2
3
4
8
7
6
5
8 pin (150 mil) SOIC
SEL
Pin 4 Spread
Direction
Spread
Percentage (%)
Part Number
0 Center ±0.5 ICS7152AM-11
Down -1.0 ICS7152AM-02
1 Center ±1.5 ICS7152AM-11
Down -3.0 ICS7152AM-02
FREQ
Pin 7 Frequency
0 16.6 to 40 MHz ICS7152AM-11
40 to 80 MHz ICS7152AM-02
1 33 to 67 MHz ICS7152AM-11
66 to 134 MHz ICS7152AM-02
Pin
Number Pin
Name Pin Type Pin Description
1 XIN Input Crystal/clock input pin.
2 XOUT Output Crystal.
3 GND Power Connect to ground.
4 SEL Input Spread modulation select.
5 CKOUT Output Spread modulation select.
6 VDD Power Connect to +3.3 V.
7 FREQ Input Frequency select.
8 XENS Output Modulation enable select.
ICS7152A
SPREAD SPECTRUM CLOCK GENERATOR SSCG
IDT™ / ICS™
SPREAD SPECTRUM CLOCK GENERATOR 3
ICS7152A REV B 011008
External Components
The ICS7152A requires a minimum number of external
components for proper operation.
Decoupling Capacitor
A decoupling capacitor of 0.01µF must be connected
between GND and VDD on pins 3 and 6, as close to these
pins as possible. For optimum device performance, the
decoupling capa citor should be mounted on th e component
side of the PCB. Avoid the use of vias in the decoupling
circuit.
Series Termination Resistor
Series termination should be used on the clock output. To
series ter m in at e a 50Ω trace (a commonl y use d trace
impedance) place a 27Ω resistor in series with the clock line,
as close to the clock output pin as possible. The nominal
impedance of the clock output is 25Ω.
PCB Layout Recommendations
For optimum device performance and lowest output pha se
noise, the following guidelines should be observed.
1) The 0.01µF d ecoupling ca pacit or sh ou ld be mount ed o n
the componen t side of the board as close to the VDD pin as
possible. No vias should be used between the decoupling
capacitor and VDD pin. The PCB t race to VDD pin should
be k ept as short as possible , as should the PCB trace t o the
ground via.
2) To minimize EMI, the 27Ω series termination resistor (if
needed) shou ld be placed close to the clock output.
3) An optimum layout is one with all components on the
same side of the board, minimizing vias through other signal
layer s. Other signal traces should be routed away from the
ICS7152A. This includes signa l traces just underneath the
de vice, or on la yers adjacent t o the ground plane la yer used
by the device.
Crystal Information
The crystal used should be a fundamental mode, parallel
resonant. Crystal capacitors should be connected from pins
X1 to ground and X2 to grou nd to optimize the initial
accuracy. The value of these capacitors is given by the
following equation:
Crystal caps (pF) = (CL - 6) x 2
In the equation, CL is the crystal load capaci tance. So, f or a
crystal with a 16 pF load capacitan ce, two 20 pF [(16 -6) x 2]
capacitors should be used .
Spread Spectrum Profile
The ICS7152A lo w EMI clock generator uses a triangular
frequency modulation profile for optimal down stream
tracking of ze ro delay buffers and other PLL devices. The
frequency modulation amplitude is constant with variations
of the input frequency.
Time
Frequency
Modulation Rate
ICS7152A
SPREAD SPECTRUM CLOCK GENERATOR SSCG
IDT™ / ICS™
SPREAD SPECTRUM CLOCK GENERATOR 4
ICS7152A REV B 011008
Absolute Maximum Ratings
Stresses above the ratings listed below can cause permanent damage to the ICS7152A. These ra tings, which are
standard values for ICS commercially rated parts, are stress ratings only. Functional operation of the device at
these or any other conditions above those indicated in the operational sections of the specifications is not implied.
Exposure to absolute maximum rating conditions for extended periods can affect product reliability. Electrical
parameters are guaranteed only over the recommended operating temperature range.
Overshoot/Undershoot
Recommended Operation Conditions
Item Rating
Supply Voltage , VDD -0.5 to 4.0 V
All Inputs and Outputs (referenced to GND) -0.5 V to VDD+0.5 V
Ambient Operating Temperature -40 to +85°C
Storage Temperature -55 to +125°C
Junction Temperature -40 to +125°C
Soldering Temperature 260°C
Overshoot (VIOVER) VDD + 1.0 V (tOVER < 50 ns) max
Undershoot (VIUNDER) GND - 1.0 V (tUNDER < 50 ns) min
Parameter Min. Typ. Max. Units
Ambient Operating Temperature -40 +85 °C
Power Supply Voltage (measured in respect to GND) +3.0 3.3 3.6 V
Input pin
VIOVER < VDD + 1.0 V
VIUNDER < GND - 1.0 V
tOVER < 50 ns
tUNDER < 50 ns
VDD
GND
ICS7152A
SPREAD SPECTRUM CLOCK GENERATOR SSCG
IDT™ / ICS™
SPREAD SPECTRUM CLOCK GENERATOR 5
ICS7152A REV B 011008
DC Electrical Characteristics
Unless stated otherwise, VDD = 3.3 V ±0.3 V, Ambient Temperature -40 to +85°C
Parameter Symbol Conditions Min. Typ. Max. Units
Operating Voltage VDD 3.0 3.3 3.6 V
Supply Current IDD No load, at 3.3 V,
output = 24 MHz 10 14 mA
Input High Voltage VIH
SEL, FREQ, XENS VDD x 0.8 VDD + 0.3 V
XIN, Input slew rate
3 V/ns, 16.6 to 100
MHz
VDD x 0.8 VDD + 0.3 V
XIN, Input slew rate
3 V/ns, 100 to 134
MHz
VDD x 0.9 VDD + 0.3 V
Input Low Voltage VIL
SEL, FREQ, XENS GND VDD x 0.20 V
XIN, Input slew rate
3 V/ns, 16.6 to 100
MHz
GND VDD x 0.20 V
XIN, Input slew rate
3 V/ns, 100 to 134
MHz
GND VDD x 0.10 V
Output High Voltage VOH CKOUT, IOH = -4 mA VDD - 0.5 VDD V
Output Low Voltage VOL CKOUT, IOL = 4 mA GND 0.4 V
Input Capacitance CIN XIN, SEL, XENS 16 pF
Load Capacitance CL
CKOUT, 16.6 to 67
MHz 15 pF
CKOUT, 67 to 100
MHz 10 pF
CKOUT, 100 to 134
MHz 7pF
Output Impedance ZOCKOUT, 16.6 to 134
MHz 25 Ω
ICS7152A
SPREAD SPECTRUM CLOCK GENERATOR SSCG
IDT™ / ICS™
SPREAD SPECTRUM CLOCK GENERATOR 6
ICS7152A REV B 011008
AC Electrical Characteristics
Unless stated otherwise, VDD = 3.3 V ±0.3 V, Ambient Temperature -40 to +85° C
Note 1: Contact ICS Applications for more information.
Parameter Symbol Conditions Min. Typ. Max. Units
Oscillation Frequency fXXIN, XOUT,
Fundamental
oscillation
16.6 40 MHz
XIN, XOUT, 3rd over
tone, note 1 40 48 MHz
Input Frequency fIN XIN, ICS7152A-11 16.6 67 MHz
XIN, ICS7152A-02 40 134 MHz
Output Frequency fOUT CKOUT, ICS7152A-11 16.6 67 MHz
CKOUT, ICS7152A-02 40 134 MHz
Input Clock Duty Cycle tDCI XIN, 16.6 to 100 MHz 40 50 60 %
XIN, 100 to 134 MHz 45 50 55 %
Output Clock Duty Cycle tDCC CKOUT, 1.5 V 40 60 %
Output Slew Rate CKOUT, 0.4 to 2.4 V,
load capacitance 15 pF 0.5 TBD 3.0 V/ns
Cycle to Cycle Jitter tJC No load, standard
deviation TBD 100 ps
Lock Time tLK CKOUT 2 5 ms
Modulation Frequency fMOD CKOUT=TBD 33 kHz
ICS7152A
SPREAD SPECTRUM CLOCK GENERATOR SSCG
IDT™ / ICS™
SPREAD SPECTRUM CLOCK GENERATOR 7
ICS7152A REV B 011008
Input Frequency (fIN = 1/tIN)
Output Slew Rate
Thermal Characteristics
Parameter Symbol Conditions Min. Typ. Max. Units
Thermal Resistance Junction to
Ambient θJA Still air 150 °C/W
θJA 1 m/s air flow 140 °C/W
θJA 3 m/s air flow 120 °C/W
Thermal Resistance Junction to Case θJC 40 °C/W
CKIN
tIN
0.8 VDD
CKOUT
SR = (2.4 - 0.4) /tr, SR = (2.4 - 0.4) /tf
tr
2.4 V
tf
0.4 V
ICS7152A
SPREAD SPECTRUM CLOCK GENERATOR SSCG
IDT™ / ICS™
SPREAD SPECTRUM CLOCK GENERATOR 8
ICS7152A REV B 011008
Package Outline and Package Dimensions (8-pin SOIC, 150 Mil. Body)
Package dimensions are kept current with JEDEC Publication No. 95
INDEX
AREA
1 2
8
D
E
SEATING
PLANE
A1
A
e
- C -
B
.10 (.004) C
C
L
H
h x 45
*For reference only. Controlling dimensions in mm.
Millimeters Inches*
Symbol Min Max Min Max
A 1.35 1.75 .0532 .0688
A1 0.10 0.25 .0040 .0098
B 0.330.51.013.020
C 0.19 0.25 .0075 .0098
D 4.80 5.00 .1890 .1968
E 3.80 4.00 .1497 .1574
e 1.27 BASIC 0.050 BASIC
H 5.80 6.20 .2284 .2440
h 0.250.50.010.020
L 0.401.27.016.050
α0°8°0°8°
ICS7152A
SPREAD SPECTRUM CLOCK GENERATOR SSCG
IDT™ / ICS™
SPREAD SPECTRUM CLOCK GENERATOR 9
ICS7152A REV B 011008
Ordering Information
Parts that are ordered with a “LF” suffix to the part number are the Pb-Free configuration and are RoHS compliant.
While the information presented herein has been checked for both accuracy and reliability, Integrated Device Technology (IDT) 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 requir ing extended temperature range, high reliability, or other extraordinary environmental requirements are not
recommended without additional processin g by IDT. IDT reserves the right to change any circuitry or specifications without notice. IDT
does not authorize or warrant any IDT product for use in life support devices or critical medical instruments.
Part / Order Number Marking Shipping Packaging Package Temperature
ICS7152AM-02 7152AM02 Tubes 8-pin SOIC 0 to +70° C
ICS7152AM-02T 7152AM02 Tape and Reel 8-pin SOIC 0 to +70° C
ICS7152AM-02LF 152AM02L Tubes 8-pin SOIC 0 to +70° C
ICS7152AM-02LFT 152AM02L Tape and Reel 8-pin SOIC 0 to +70° C
ICS7152AMI-02 152AMI02 Tubes 8-pin SOIC -40 to +85° C
ICS7152AMI-02T 152AMI02 Tape and Reel 8-pin SOIC -40 to +85° C
ICS7152AMI-02LF 52AMI02L Tubes 8-pin SOIC -40 to +85° C
ICS7152AMI-02LFT 52AMI02L Tape and Reel 8-pin SOIC -40 to +85° C
ICS7152AM-11 7152AM11 Tubes 8-pin SOIC 0 to +70° C
ICS7152AM-11T 7152AM11 Tape and Reel 8-pin SOIC 0 to +70° C
ICS7152AM-11LF 7152A11L Tubes 8-pin SOIC 0 to +70° C
ICS7152AM-11LFT 7152A11L Tape and Reel 8-pin SOIC 0 to +70° C
ICS7152AMI-11 7152AI11 Tubes 8-pin SOIC -40 to +85° C
ICS7152AMI-11T 7152AI11 Tape and Reel 8-pin SOIC -40 to +85° C
ICS7152AMI-11LF 152AI11L Tubes 8-pin SOIC -40 to +85° C
ICS7152AMI-11LFT 152AI11L Tape and Reel 8-pin SOIC -40 to +85° C
ICS7152A
SPREAD SPECTRUM CLOCK GENERATOR SSCG
IDT™ / ICS™
SPREAD SPECTRUM CLOCK GENERATOR 10
ICS7152A REV B 011008
Revision History
Rev. Originator Date Description of Change
A J. Sarma 10/20/05 Rev A; new device/datasheet.
B 01/10/08 Updated the -11 device markings.
© 2006 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to change without notice. IDT and the IDT logo are trademarks of Integrated Device
Technology, Inc. Accelerated Thinking is a service mark of Integrated Device Technology, Inc. All other brands, product names and marks are or may be trademarks or registered
trademarks used to identify products or services of their respective owners.
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ICS7152A
SPREAD SPECTRUM CLOCK GENERATOR SSCG
