DATASHEET
ZERO DELAY, LOW SKEW BUFFER
Description
The ICS574 is a low jitter, low-skew, high performance
PLL-based zero delay buffer for high speed applications.
Based on IDT’s proprietary low jitter Phase Locked Loop
(PLL) techniques, the device provides four low skew
outputs at speeds up to 160 MHz at 3.3 V. When one of the
outputs is connected directly to FBIN, the rising edge of
each output is aligned with the rising edge of the input
clock. External delay elements connected in the feedback
loops will cause the outputs to occur before the inputs by
the amount of propagation delay of the external element.
ICS574
Features
•
•
•
•
•
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Packaged in 8 pin narrow SOIC, Pb (lead) free available
Zero input-to-output delay
Four 1X outputs
Output to output skew is less than 150 ps
Output clocks up to 160 MHz at 3.3 V
External feedback path for output edge placement
Spread Smart™ technology works with spread spectrum
clock generators
TTL levels at 3.3 V
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Full CMOS outputs with 18 mA output drive capability at
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Advanced, low power, sub-micron CMOS process
•
Operating voltage from 3.0 to 5.5 V
•
Industrial temperature version available
NOTE: EOL for non-green parts to occur on 5/13/10
per PDN U-09-01
Block Diagram
CLK1
FBIN
CLKIN
CLK2
PLL
CLK3
CLK4
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Pin Assignment
CLKIN
CLK1
CLK2
GND
1
2
3
4
8
7
6
5
FBIN
CLK4
CLK3
VDD
Pin Descriptions
Pin
Number
1
2, 3, 6, 7
4
5
8
Pin
Name
CLKIN
CLK1:4
GND
VDD
FBIN
Pin
Type
Input
Output
Power
Power
Input
Clock Outputs (4).
Connect to ground.
Pin Description
Clock input. Connect to input clock source.
Power supply. Connect both pins to same voltage (either 3.3 V or 5 V).
Feedback input.
IDT™/ ICS™
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External Components
The ICS574 requires a minimum number of external components for proper operation. Decoupling capacitors of
0.1µF should be connected between VDD and GND on pins 4 and 5, as close to the device as possible. A series
termination resistor of 33Ω may be used close to the pin for each clock output to reduce reflections.
Absolute Maximum Ratings
Stresses above the ratings listed below can cause permanent damage to the ICS574. 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.
Item
Supply Voltage, VDD (referenced to ground)
All Inputs and Outputs
Electrostatic Discharge (MIl-STD-883)
Ambient Operating Temperature
Soldering Temperature (10 seconds max.)
Junction Temperature
Storage Temperature
-0.5 V to 7 V
Rating
-0.5 V to VDD+0.5 V
2000 V (minimum)
-40° C to +85° C
260° C
150° C
-65 to +150° C
IDT™/ ICS™
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DC Electrical Characteristics
Unless stated otherwise,
VDD = 3.3 V,
Ambient Temperature -40 to +85° C
Parameter
Operating Supply Voltage
Input High Voltage
Input Low Voltage
Output High Voltage, CMOS
level
Output High Voltage
Output Low Voltage
IDD Operating Supply Current
Short Circuit Current
Input Capacitance
Symbol
VDD
V
IH
V
IL
V
OH
V
OH
V
OL
I
OS
C
IN
Conditions
Min.
3
VDD/2+1
Typ.
Max.
5.5
VDD/2-1
Units
V
V
V
V
V
I
OH
= -5 mA
I
OH
= -18 mA
I
OL
= 18 mA
No load (Note 2)
Each output
VDD-0.4
2.4
0.4
36
±65
7
V
mA
mA
pF
AC Electrical Characteristics
Unless stated otherwise,
VDD = 3.3 V,
Ambient Temperature -40 to +85° C
Parameter
Input Frequency, clock
Output Frequency, clock
Output Clock Rise Time
Output Clock Fall Time
Output Clock Duty Cycle, 3.3 V
Device-to-device Skew, equally
loaded
Outpu-to-output Skew, equally
loaded
Maximum Absolute Jitter
Cycle-to-cycle Jitter, 15 pF loads
Symbol
f
IN
Conditions
FBIN from CLK4
FBIN from CLK4
0.8 to 2.0 V, 15 pF load
2.0 to 0.8 V, 15 pF load
At 1.4 V
Rising edges at VDD/2
Rising edges at VDD/2
Min.
20
20
Typ.
Max. Units
160
160
1.5
1.5
MHz
MHz
ns
ns
%
ps
ps
ps
250
ps
40
50
60
700
150
170
66.67 MHz outputs
Notes:
1. Stresses beyond those listed in Absolute Maximum Ratings can permanently damage the device. Prolonged
exposure to levels above the operating limits but below the Absolute Maximum Ratings may affect device reliability.
2. With CLKIN = 160 MHz, FBIN to CLK4.
Using Spread Spectrum Input Clocks
The ICS574 uses IDT’s Spread Smart technology, allowing it to accurately track (pass through) any clocks that
implement spread spectrum techniques.
IDT™/ ICS™
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Thermal Characteristics
Parameter
Thermal Resistance Junction to
Ambient
Symbol
θ
JA
θ
JA
θ
JA
θ
JC
Ψ
JT
Conditions
Still air
1 m/s air flow
3 m/s air flow
Still air
Min.
Typ.
150
140
120
40
20
Max. Units
°
C/W
°
C/W
°
C/W
°
C/W
°
C/W
Thermal Resistance Junction to Case
Thermal Resistance Junction to Top
of Case
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