ICS ICS571

PRELIMINARY INFORMATION
ICS571
Low Phase Noise Zero Delay Buffer
Description
Features
The ICS571 is a high speed, high output drive, low
phase noise Zero Delay Buffer (ZDB) which
integrates ICS’ proprietary analog/digital Phase
Locked Loop (PLL) techniques. ICS introduced
the world standard for these devices in 1992 with
the debut of the AV9170, and updated that with
the ICS570. The ICS571, part of ICS’
ClockBlocks™ family, was designed to operate at
higher frequencies, with faster rise and fall times,
and with lower phase noise. The zero delay feature
means that the rising edge of the input clock aligns
with the rising edges of both outputs, giving the
appearance of no delay through the device. There
are two outputs on the chip, one being a low-skew
divide by two of the other.
• Packaged in 8 pin SOIC.
• Can function as low phase noise x2 multiplier.
• Low skew outputs. One is ÷2 of other.
• Input clock frequency up to 160 MHz at 3.3V.
• Phase noise of better than -100 dBc/Hz from
1kHz to 1MHz offset from carrier
• Can recover poor input clock duty cycle.
• Output clock duty cycle of 45/55 at 3.3V.
• High drive strength for >100 MHz outputs.
• Full CMOS clock swings with 25mA drive
capability at TTL levels.
• Advanced, low power CMOS process.
• Operating voltages of 3.0 to 5.5 V.
The chip is ideal for synchronizing outputs in a
large variety of systems, from personal computers
to data communications to video. By allowing offchip feedback paths, the ICS571 can eliminate the
delay through other devices. The use of dividers in
the feedback path will enable the part to multiply
by more than two.
Block Diagram
ICLK
FBIN
Phase
Detector,
Charge
Pump, and
Loop Filter
Voltage
Controlled
Oscillator
Output
Buffer
CLK
Output
Buffer
CLK/2
÷2
External feedback can come from CLK or CLK/2 (see table on page 2).
1
Revision 072899
Printed 11/14/00
Integrated Circuit Systems, Inc.•525 Race Street•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS 571 B
PRELIMINARY INFORMATION
ICS571
Low Phase Noise Zero Delay Buffer
Pin Assignment
ICLK
1
8
FBIN
VDD
2
7
CLK
GND
3
6
VDD
CLK/2
4
5
GND
Feedback Configuration Table and Frequency Ranges (at 3.3V)
Feedback From
CLK
CLK
Input clock frequency
CLK/2
2xInput clock frequency
CLK/2
Input clock frequency/2
Input clock frequency
Input Range
20 -160 MHz
10 - 80 MHz
Pin Descriptions
Number
1
2
3
4
5
6
7
8
Name
ICLK
VDD
GND
CLK/2
GND
VDD
CLK
FBIN
Type
CI
P
P
O
P
P
O
CI
Description
Reference clock input.
Connect to +3.3V or +5V. Must be same as other VDD.
Connect to ground.
Clock output per Table above. Low skew divide by two of pin 7 clock.
Connect to ground.
Connect to +3.3V or +5V. Must be same as other VDD.
Clock output per Table above.
Feedback clock input. Connect to CLK or CLK/2 per table above.
Key: CI = clock input, I = input, O = output, P = power supply connection
External Components
The ICS571 requires a 0.01 µF decoupling capacitor to be connected between VDD and GND on each
side of the chip (between pins 2 and 3, and also between pins 6 and 5). They must be connected close to
the ICS571 to minimize lead inductance. No external power supply filtering is required for this device.
A 33 Ω terminating resistor can be used next to each output pin.
2
Revision 072899
Printed 11/14/00
Integrated Circuit Systems, Inc.•525 Race Street•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS 571 B
PRELIMINARY INFORMATION
ICS571
Low Phase Noise Zero Delay Buffer
Electrical Specifications
Parameter
Conditions
ABSOLUTE MAXIMUM RATINGS (Note 1)
Supply Voltage, VDD
Referenced to GND
Inputs
Referenced to GND
Clock Output
Referenced to GND
Ambient Operating Temperature
Soldering Temperature
Max of 10 seconds
Storage temperature
DC CHARACTERISTICS (VDD = 5.0V or 3.3V unless otherwise noted)
Operating Voltage, VDD
Input High Voltage, VIH, ICLK, FBIN
Pins 1, 8
Input Low Voltage, VIL, ICLK, FBIN
Pins 1, 8
Output High Voltage, VOH, CMOS level
IOH=-4mA
Output High Voltage, VOH
IOH=-25mA
Output Low Voltage, VOL
IOL=25mA
IDD Operating Supply Current, 133 in, 133 out No Load, 3.3V
IDD Operating Supply Current, 50 in, 100 out No Load, 3.3V
Short Circuit Current
Each Output
Input Capacitance, ICLK, FBIN
AC CHARACTERISTICS (VDD = 5.0V or 3.3V unless otherwise noted)
Input Frequency, clock input
FB from CLK
Input Frequency, clock input
FB from CLK/2
Skew CLK/2 with respect to CLK
Note 2
Input clock to output connected to FBIN
Note 2
Output Clock Rise Time, 5V
0.8 to 2.0V, 15 pF load
Output Clock Fall Time, 5V
2.0 to 0.8V, 15 pF load
Output Clock Rise Time, 3.3V
0.8 to 2.0V, 15 pF load
Output Clock Fall Time, 3.3V
2.0 to 0.8V, 15 pF load
Output Clock Duty Cycle, 5V
at VDD/2
Output Clock Duty Cycle, 3.3V
at VDD/2
Absolute Clock Period Jitter, CLK, note 3
Deviation from mean
One Sigma Clock Period Jitter, CLK, note 3
Phase Noise, relative to carrier
1kHz offset
Phase Noise, relative to carrier
100kHz offset
Notes:
Minimum
Typical
-0.5
-0.5
0
-65
3
VDD/2+1
VDD/2
VDD/2
Maximum
Units
7
VDD+0.5
VDD+0.5
70
260
150
V
V
V
°C
°C
°C
5.5
V
V
V
V
V
V
mA
mA
mA
pF
VDD/2-1
VDD-0.4
2.4
0.4
34
26
±100
5
20
10
150
-500
40
45
500
0.3
0.4
0.45
0.55
52 to 55
49 to 51
±80
50
-105
-115
160
80
850
500
60
55
MHz
MHz
ps
ps
ns
ns
ns
ns
%
%
ps
ps
dBc/Hz
dBc/Hz
1. Stresses beyond these can permanently damage the device.
2. Assumes clocks with same rise time, measured from rising edges at VDD/2. Measured with 33Ω
termination resistors and 15 pF loads. Applies to both 3.3V and 5V operation.
3. CLK/2 has lower jitter (both absolute and one sigma, in ps) than CLK.
3
Revision 072899
Printed 11/14/00
Integrated Circuit Systems, Inc.•525 Race Street•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS 571 B
PRELIMINARY INFORMATION
ICS571
Low Phase Noise Zero Delay Buffer
Package Outline and Package Dimensions
8 pin SOIC
E
H
Pin 1
h x 45°
D
Q
A
c
e
b
L
Symbol
A
b
D
E
H
e
h
L
Q
Inches
Min
Max
0.055 0.068
0.013 0.019
0.185 0.200
0.150 0.160
0.225 0.245
.050 BSC
0.015
0.016 0.035
0.004
0.01
Millimeters
Min
Max
1.397 1.7272
0.330
0.483
4.699
5.080
3.810
4.064
5.715
6.223
1.27 BSC
0.381
0.406
0.889
0.102
0.254
Ordering Information
Part/Order Number
ICS571M
ICS571MT
Marking
ICS571M
ICS571M
Package
8 pin SOIC
8 pin SOIC on tape and reel
Temperature
0 to 70 °C
0 to 70 °C
While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems (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.
ClockBlocks is a trademark of ICS
4
Revision 072899
Printed 11/14/00
Integrated Circuit Systems, Inc.•525 Race Street•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax
MDS 571 B