DATASHEET
LOW EMI, SPREAD MODULATING, CLO C K GENERATO R ICS91730
IDT®
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR 1
ICS91730 REV F 061611
Features/Benefits
•ICS91730 is a Spread Spectrum Clock targeted for
Mobile PC and LCD panel applications that generates an
EMI-optimized clock signal (EMI peak reduction of 7-14
dB on 3rd-19th harmonics) through use of Spread
Spectrum techniques.
•ICS91730 focuses on the lower input frequency range of
14.318 to 80.00 MHz with a spread modulation of 20kHz
to 40kHz.
Specifications
•Supply Voltages: VDD = 3.3V ±0.3V
•Frequency range: 14.318 MHz <Fin > 80 MHz
•Cyc to Cyc jitter: <150ps
•Output duty cycle 45-55%
•0°C to +85°C operation
•8-pin SOIC
•Reference input
Pin Configuration
Functionality
Block Diagram
CLKIN 18
PD #*
VDD 27
SC LK
GND 36
SD ATA
CLKOUT 45
REF_OUT/FS_IN1*
8 Pin SOIC
* Internal Pull-Up Resistor
FSIN_1
0 -0.8 down spread
1 -1.25 down spread27.00MHz in --> 27.00MHz out
MHz Spread % default
14.318 MHz in --> 27MHz out
ICS91730
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR
IDT®
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR 2
ICS91730 REV F 061611
Pin Descriptions
PIN # PIN NAME PIN
TYPE DESCRIPTION
1CLKIN PWRIn
p
ut for reference clock.
2VDD INPower su
pp
l
y
, nominal 3.3
V
3 GND OUT Ground
p
in .
4 CLKOUT I/O Modulated clock out
p
ut.
Un-modulated 3.3V reference clock out
p
ut.
Fre
uenc
select latch in
ut. Refer to the functionalit
table.
6 SDATA PWR Data
p
in for SMBus circuitr
y
, 5V tolerant.
7 SCLK PWR Clock
p
in of SMBus circuitr
y
, 5V tolerant.
8PD#* PWR
Asynchronous active low input pin, with 120Kohm internal pull-up resistor,
used to pow er down the device. The internal clocks are disabled and the
VCO and the cr
y
stal are sto
pp
ed.
* Internal Pull-Up Resistor ** Internal Pull-Down Resistor
I/OREF_OUT/FS_IN1*5
ICS91730
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR
IDT®
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR 3
ICS91730 REV F 061611
Table 1: Frequency Configuration (see I2C Byte0)
Above is the hard coded 5 bit (32 entry) ROM table.
FS3:0 are ONLY accessible through I2C software programming bits (byte0 bits5:7). FS4 can also be decoded from FS_IN1
latched input hardware pins.
FS_IN1 → FS4. Upon power-up the default is to use hardware selection of FS_IN1 latched value.
FS3 = 0, FS2 = 0, FS1 = 0, FS0 = 1 upon power-up (refer to the functionality table on page 1).
To access non-default spread entries in the ROM, byte0 programming should be used. In order to change the power up
default of FS_IN1 = 1 (-1.25% down spread) to any other spread % entry, first change byte0bit 0 to software selection by
switching this bit to a ‘1’ and then program the desired percentage by changing byte0 bits 7:3.
FS4 FS3 FS2 FS1 FS0
Sprd Typ
e
Sprd %
00000 0.60
00001 0.8 0
00010 1.0 0
00011 1.25
00100 1.50
00101 2.0 0
00110 0.50
00111 1.0 0
01000 0.60
01001 1.00
01010 -0.80
01011CTR SPD
+/-0.3
01100
1.50
01101 1.7 5
01110 2.00
01111 2.50
10000 3.00
10001
1.25
10010 0.40
10011 0.50
10100 0.70
10101 1.00
10110 1.20
10111 1.50
11000 0.60
11001 0.80
11010 1.00
11011 1.2 5
11100 1.5 0
11101 2.0 0
11110 0.50
11111 1.0 0
DOWN
SPREAD
(-)
DOWN
SPREAD
(-)
48in/48out
66in/66out
DOWN
SPREAD
(-)
CENTER
SPD (+/-)
14in/27out
DOWN
SPREAD
(-)
CENTER
SPD (+/-)
14in/14out
27in/27out
CENTER
SPD (+/-)
ICS91730
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR
IDT®
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR 4
ICS91730 REV F 061611
General SMBus Serial Interface Information
How to Write
•Controller (host) sends a start bit
•Controller (host) sends the write address
•IDT clock will acknowledge
•Controller (host) sends the beginning byte location = N
•IDT clock will acknowledge
•Controller (host) sends the byte count = X
•IDT clock will acknowledge
•Controller (host) starts sending Byte N through Byte
N+X-1
•IDT clock will acknowledge each byte one at a time
•Controller (host) sends a Stop bit
How to Read
•Controller (host) will send a start bit
•Controller (host) sends the write address
•IDT clock will acknowledge
•Controller (host) sends the beginning byte location = N
•IDT clock will acknowledge
•Controller (host) will send a separate start bit
•Controller (host) sends the read address
•IDT clock will acknowledge
•IDT clock will send the data byte count = X
•IDT clock sends Byte N+X-1
•IDT clock sends Byte 0 through Byte X (if X(H) was
written to Byte 8)
•Controller (host) will need to acknowledge each byte
•Controller (host) will send a not acknowledge bit
•Controller (host) will send a stop bit
Index Block Write Operation
Controller (Host) IDT (Slave/Receiver)
TstarT bit
Slave Address
WR WRite
ACK
Beginning Byte = N
ACK
Data Byte Count = X
ACK
Beginning Byte N
X Byte
ACK
O
OO
OO
O
Byte N + X - 1
ACK
PstoP bit
Read Address Write Address
D5(H) D4(H)
Index Block Read Operation
Controller (Host) IDT (Slave/Receiver)
TstarT bit
Slave Address
WR WRite
ACK
Beginning Byte = N
ACK
RT Repeat starT
Slave Address
RD ReaD
ACK
Data Byte Count=X
ACK
X Byte
Beginning Byte N
ACK
O
OO
OO
O
Byte N + X - 1
N Not acknowledge
PstoP bit
ICS91730
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR
IDT®
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR 5
ICS91730 REV F 061611
Byte
0Pin # Name Control Function 0 1 PWD
Bit 7 - FS0 Spread/FS0 RW 1
Bit 6 - FS1 Spread/FS1 RW 0
Bit 5 FS2 Spread/FS2 RW 0
Bit 4 FS3 Spread/FS3 RW 0
Bit 3 FS4 FS4 RW 0
Bit 2 PD# Tri_Sate PD# Tri_Sate RW Hi-Z LOW 1
Bit 1 Spread Enable Spread Enable RW OFF ON 1
Bit 0 HW/SW Control
S
prea
d
S
pec
t
rum
C
on
t
ro
l
FS 3:4 Hard/Software
Select RW HW SW 0
Byte
1Pin # Name Control Function 0 1 PWD
Bit 7
REF_OUT REF_OUT_Enable RW Disable Enable 1
Bit 6
- REF_OUT Slew Rate REF-OUT RW Nominal Fast 1
Bit 5 FS-IN_1 FS-IN_1 Readback R - -
X
Bit 4
(Reserved) (Reserved)
R- -0
Bit 3 CLK_OUT Slew Rate CLK-OUT RW Nominal Fast 1
Bit 2 CLK_OUT CLK_OUT_Enable RW Disable Enable 1
Bit 1
(Reserved) (Reserved)
R- -1
Bit 0
(Reserved) (Reserved)
R- -1
Byte
2Pin # Name Control Function 0 1 PWD
Bit 7
x-
(
Reserved
)
-- -1
Bit 6
x
(
Reserved
)
(
Reserved
)
RW D isable Enable 1
Bit 5
x
(
Reserved
)
(
Reserved
)
RW D isable Enable 1
Bit 4
x
(
Reserved
)
(
Reserved
)
RW D isable Enable 1
Bit 3
x
(
Reserved
)
(
Reserved
)
RW D isable Enable 1
Bit 2
x
(
Reserved
)
(
Reserved
)
RW D isable Enable 1
Bit 1
x (Reserved) (Reserved) RW Disable Enable 1
Bit 0 x
(Reserved) (Reserved)
RW D isable Enable 1
Byte
3Pin # Name Control Function 0 1 PWD
Bit 7
X
(
Reserved
)
(
Reserved
)
RW - - 1
Bit 6
X
(
Reserved
)
(
Reserved
)
RW - - 1
Bit 5
X
(
Reserved
)
(
Reserved
)
RW - - 1
Bit 4
X
(
Reserved
)
(
Reserved
)
RW - - 1
Bit 3
x
(
Reserved
)
(
Reserved
)
RW - - 1
Bit 2
X
(
Reserved
)
(
Reserved
)
RW - - 1
Bit 1
X
(
Reserved
)
(
Reserved
)
RW - - 1
Bit 0
X
(Reserved) (Reserved)
RW - - 1
Affected Pin
Affected Pin
Affected Pin
Affected Pin
Srpead Pecentage
See Table1
These are I2C bits
only
Type
Bit Control
Type
Bit Control
Bit Control
Type
Type
Bit Control
ICS91730
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR
IDT®
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR 6
ICS91730 REV F 061611
Byte
4Pin # Name Control Function 0 1 PWD
Bit 7
X (Reserved) (Reserved) RW
--
1
Bit 6
X (Reserved) (Reserved) RW
--
1
Bit 5
X (Reserved) (Reserved) RW
--
1
Bit 4
X (Reserved) (Reserved) RW
--
1
Bit 3
X (Reserved) (Reserved) RW
--
1
Bit 2
X (Reserved) (Reserved) RW
--
1
Bit 1
X (Reserved) (Reserved) RW
--
1
Bi
t
0
X (Reserved) (Reserved) RW
--
1
Byte
5Pin # Name Control Function 0 1 PWD
Bit 7
X
(
Reserved
)
(
Reserved
)
-
--
1
Bit 6
X
(
Reserved
)
(
Reserved
)
-
--
1
Bit 5
X (Reserved) (Reserved) - - - 1
Bit 4
X (Reserved) (Reserved) - - - 1
Bit 3
X (Reserved) (Reserved) RW
--
1
Bit 2
X (Reserved) (Reserved) RW
--
1
Bit 1
X (Reserved) (Reserved) RW
--
1
Bit 0
X (Reserved) (Reserved) RW
--
1
Byte
6Pin # Name Control Function 0 1 PWD
Bit 7
X
Revision ID Bit 3
(
Reserved
)
R- -1
Bit 6
X
Revision ID Bit 2
(
Reserved
)
R- -1
Bit 5
X
Revision ID Bit 1
(Reserved)
R- -1
Bit 4
X
Revision ID Bit 0
(Reserved)
R- -1
Bit 3
X
Vendor ID Bit 3
(Reserved)
R- -1
Bit 2
X
Vendor ID Bit 2
(Reserved)
R- -1
Bit 1
X
Vendor ID Bit 1
(Reserved)
R- -1
Bit 0
X Vendor ID Bit 0
(Reserved)
R- -1
Affected Pin
Type
Bit Control
Type
Bit ControlAffected Pin
Affected Pin
Type
Bit Control
ICS91730
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR
IDT®
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR 7
ICS91730 REV F 061611
Absolute Maximum Ratings
Stresses above the ratings listed below can cause permanent damage to the ICS91730. These ratings, which are standard
values for IDT 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.
Electrical Characteristics–Input/Supply/Common Output Parameters
TA = 0 - 85°C; Supply Voltage VDD = 3.3 V +/-5%
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Input High Voltage VIH 2V
DD
+ 0.3 V
Input Low Voltage V
IL
V
SS
- 0.3 0.8 V
Input High Current I
IH
V
IN
= V
DD
-5 5 mA
Input Low Current IIL1 VIN = 0 V; Inputs with no pull-up resistors -5 mA
Powerdown Current I
D D3. 3PD
15mA
fin = 14.318MHz
2
27 41 mA
fin = 66.67MHz
2
32 50 mA
Input Frequency Fi V
DD
= 3.3 V 14.318 MHz
Pin Inductance Lpin 7nH
CIN Logic Inputs 5 pF
C
OUT
Output pin capacitance 6 pF
CINX X1 & X2 pins 27 36 45 pF
Transition time
1
T
tra ns
To 1st crossing of target frequency 3 ms
Settling time1Ts From 1st crossing to 1% target frequency 3 ms
Clk Stabilization
1T
STAB
From V
DD
= 3.3 V to 1% target frequency 3 ms
Delay
1
tPZH,tPZL Output enable delay (all outputs) 1 10 ns
1
Guaranteed by design, not 100% tested in production.
Input C apacitance1
Operating Current ID D3.3OP
2Operating current depends on both the input and output frequencies. The values shown represent the upper and lower
extremes. The higher the input/output frequency, the higher the current draw. The relationship is linear.
ICS91730
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR
IDT®
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR 8
ICS91730 REV F 061611
Electrical Characteristics–CLKOUT
Electrical Characteristics–REF
TA = 0 - 85°C; VDD
= 3.3V +/-5%; CL = 15 pF (unless otherwise specified)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Output H igh Voltage VOH 3 IOH = -1 mA 2.4 V
Output Low Voltage V
OL3
I
OL
= 1 mA 0.4
Rise Time tr3 V
OL
= 0.41V, V
OH
= 0.86V 0.5 0.6 1 ns
Fall Time tf3 VOH = 0.86V VOL = 0.41V 0.5 0.6 1 ns
Duty Cycle dt3
measurement from differential wavefrom -
0.35V to +035V 45 50 55 %
Jitter, Cycle to cycle tjcyc-cyc
1
VT = 50% 50 150 ps
1
Guaranteed by design, not 100% tested in production.
TA = 0 - 85°C; VDD
= 3.3V +/-5%; CL = 15 pF (unless otherwise specified)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Output Frequency FO1 14.318 MHz
Output Impedance R
DSP1
1
V
O
= V
DD
*(0.5) 20 48 60 Ω
Output H igh Voltage VOH
1
IOH = -1 mA 2.4 V
Output Low Voltage V
OL
1
I
OL
= 1 mA 0.4 V
Output High Current I
OH
1
V OH@MIN = 1 .0 V, V OH@MAX = 3.135 V -29 -23 mA
Output Low Current I
OL
1
V
OL @ MIN
= 1.95 V, V
OL @MAX
= 0.4 V 29 27 mA
Rise Time tr1
1VOL = 0.4 V, VOH = 2.4 V 1 1.2 2 ns
Fall Time t
f1
1
V
OH
= 2.4 V, V
OL
= 0.4 V 1 1.2 2 ns
Duty Cycle d
t1
1V
T
= 1.5 V 455155%
Jitter tjcyc-cyc
1
VT = 1.5 V 105 300 ps
1
Guaranteed by design, not 100% tested in production.
ICS91730
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR
IDT®
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR 9
ICS91730 REV F 061611
Package Outline and Package Dimensions (8-pin SOIC, 150 Mil. Body)
Package dimensions are kept current with JEDEC Publication No. 95
Ordering Information
"LF" suffix to the part number are the Pb-Free configuration and are RoHS compliant.
“A” is the device revision designator (will not correlate with the datasheet revision).
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 requiring extended temperature range, high reliability, or other extraordinary environmental requirements are not
recommended without additional processing 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.
INDEX
AREA
1 2
8
D
E
SEATING
PLANE
A1
A
e
- C -
B
.10 (.004) C
C
L
H
h x 45
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°
Part / Order Number Shipping Packaging Package Temperature
91730AMLF Tubes 8-pin SOIC 0 to +85°C
91730AMLFT Tape and Reel 8-pin SOIC 0 to +85°C
ICS91730
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR
IDT®
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR 10
ICS91730 REV F 061611
Revision History
Issue Date Who Description Page #
06/25/04 Add Lead Free package description to Ordering Information 10
06/29/04 Add Revision History table to datasheet. 11
05/23/05
1. Revise ABS max ratings.
2. Updated REF Electrical Characteristics table.
3. Updated LF ordering information from "lead free" to "RoHS compliant". 8-10
06/04/08 Updated MLF ordering info 9
06/16/11 RDW
1. Added operating current specs that were inadvertantly ommitted
2. Updated ordering info to latest format
3. Changed CL from "10-20 pF" to 15 pF 1, 7-9
Rev.
C
B
D
E
F
© 2011 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to change without notice. IDT, ICS, 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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Corporate Headquarters
Integrated Device Technology, Inc.
www.idt.com
For Sales
800-345-7015
408-284-8200
Fax: 408-284-2775
For Tech Support
www.idt.com/go/clockhelp
pcclockhelp@idt.com
Innovate with IDT and accelerate your future networks. Contact:
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ICS91730
LOW EMI, SPREAD MODULATING, CLOCK GENERATOR SYNTHESIZERS