ICS651
MDS 651 C
1
Revision 120805
I n t e gra t e d C i r c u i t S y s t e m s
5 2 5 R a c e S t r e e t , S a n J o s e, C A 9 5 1 2 6
t e l ( 4 0 8 ) 2 9 7 - 1 2 0 1
w w w. i c s t . c o m
L
OW
S
KEW
1
TO
4 C
LOCK
B
UFFER
Description
The ICS651 is a low skew, single input to four output,
clock buffer. Part of ICS' ClockBlocks
TM
family, this is a
low skew, small clock buffer.
ICS makes many non-PLL and PLL based low skew
output devices as well as Zero Delay Buffers to
synchronize clocks. Contact us for all of your clocking
needs.
Features
Low skew outputs (250 ps)
Packaged in 8-pin SOIC
Available in Pb (lead) free package
Low power CMOS technology
Operating Voltages of 1.8 V to 2.5 V
Output Enable pin tri-states outputs
3.3 V tolerant input clock
Industrial temperature range
Block Diagram
Q0
ICLK
Q1
Q2
Q3
Output Enable
L
OW
S
KEW
1
TO
4 C
LOCK
B
UFFER
MDS 651 C
2
Revision 120805
I n t e gr a t e d C i r c u i t S y s t e m s
5 2 5 R a c e S t r e e t , S a n J o s e, C A 9 5 1 2 6
t e l ( 4 0 8 ) 2 9 7 - 1 2 0 1
w w w. i c s t . c o m
ICS651
Pin Assignment
Pin Descriptions
External Components
A minimum number of external components are required for proper operation. A decoupling capacitor of
0.01
F should be connected between VDD on pin 7 and GND on pin 6, as close to the device as possible.
A 33
series terminating resistor may be used on each clock output if the trace is longer than 1 inch.
To achieve the low output skew that the ICS651 is capable of, careful attention must be paid to board
layout. Essentially, all four outputs must have identical terminations, identical loads and identical trace
geometries. If they do not, the output skew will be degraded. For example, using a 30
series termination
on one output (with 33
on the others) will cause at least 15 ps of skew.
1
2
3
4
5
6
7
8
ICLK
Q1
Q2
Q3
Q4
OE
VDD
GND
Pin
Number
Pin
Name
Pin
Type
Pin Description
1
ICLK
Input
Clock Input. 3.3 V tolerant input.
2
Q1
Output
Clock Output 1.
3
Q2
Output
Clock Output 2.
4
Q3
Output
Clock Output 3.
5
Q4
Output
Clock Output 4.
6
GND
Power
Connect to ground.
7
VDD
Power
Connect to +1.8 V or +2.5 V.
8
OE
Input
Output Enable. Tri-states outputs when low. Connect to VDD for normal operation.
L
OW
S
KEW
1
TO
4 C
LOCK
B
UFFER
MDS 651 C
3
Revision 120805
I n t e gr a t e d C i r c u i t S y s t e m s
5 2 5 R a c e S t r e e t , S a n J o s e, C A 9 5 1 2 6
t e l ( 4 0 8 ) 2 9 7 - 1 2 0 1
w w w. i c s t . c o m
ICS651
Absolute Maximum Ratings
Stresses above the ratings listed below can cause permanent damage to the ICS651. These ratings, 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.
Recommended Operation Conditions
Item
Rating
Supply Voltage, VDD
7 V
Output Enable and All Outputs
-0.5 V to VDD+0.5 V
ICLK
-0.5 V to 3.6 V (VDD > 0V)
Ambient Operating Temperature
-40 to +85
C
Storage Temperature
-65 to +150
C
Junction Temperature
125
C
Soldering Temperature
260
C
Parameter
Min.
Typ.
Max.
Units
Ambient Operating Temperature
-40
+85
C
Power Supply Voltage (measured in respect to GND)
+1.6
+3.6
V
L
OW
S
KEW
1
TO
4 C
LOCK
B
UFFER
MDS 651 C
4
Revision 120805
I n t e gr a t e d C i r c u i t S y s t e m s
5 2 5 R a c e S t r e e t , S a n J o s e, C A 9 5 1 2 6
t e l ( 4 0 8 ) 2 9 7 - 1 2 0 1
w w w. i c s t . c o m
ICS651
DC Electrical Characteristics
VDD=1.8 V
5%
, Ambient temperature -40 to +85
C, unless stated otherwise
Notes: 1. Nominal switching threshold is VDD/2
VDD=2.5 V 5%
, Ambient temperature -40 to +85
C, unless stated otherwise
Notes: 1. Nominal switching threshold is VDD/2
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Units
Operating Voltage
VDD
1.71
1.89
V
Input High Voltage
V
IH
Note 1, ICLK, OE
1.17
3.6
V
Input Low Voltage
V
IL
Note 1, ICLK, OE
0.63
V
Output High Voltage
V
OH
I
OH
= -6 mA
1.35
V
Output Low Voltage
V
OL
I
OL
= 6 mA
0.45
V
Operating Supply Current
IDD
No load, 133 MHz
25
mA
Nominal Output Impedance
Z
O
20
Input Capacitance
C
IN
ICLK, OE pin
5
pF
Short Circuit Current
I
OS
28
mA
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Units
Operating Voltage
VDD
2.375
2.625
V
Input High Voltage, ICLK
V
IH
Note 1, ICLK, OE
1.7
3.6
V
Input Low Voltage, ICLK
V
IL
Note 1, ICLK, OE
0.7
V
Output High Voltage
V
OH
I
OH
= -8 mA
2
V
Output Low Voltage
V
OL
I
OL
= 8mA
0.4
V
Operating Supply Current
IDD
No load, 133 MHz
50
mA
Nominal Output Impedance
Z
O
20
Input Capacitance
C
IN
ICLK, OE pin
5
pF
Short Circuit Current
I
OS
50
mA
L
OW
S
KEW
1
TO
4 C
LOCK
B
UFFER
MDS 651 C
5
Revision 120805
I n t e gr a t e d C i r c u i t S y s t e m s
5 2 5 R a c e S t r e e t , S a n J o s e, C A 9 5 1 2 6
t e l ( 4 0 8 ) 2 9 7 - 1 2 0 1
w w w. i c s t . c o m
ICS651
AC Electrical Characteristics
VDD = 1.8 V 5%
, Ambient Temperature -40 to +85
C, unless stated otherwise
VDD = 2.5 V 5%
, Ambient Temperature -40 to +85
C, unless stated otherwise
Notes: 1. With rail to rail input clock
2. Between any 2 outputs with equal loading.
Thermal Characteristics
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Units
Input Frequency
0
166
MHz
Output Rise Time
t
OR
0.63 V to 1.17 V
1.0
1.5
ns
Output Fall Time
t
OF
1.17 V to 0.63 V
1.0
1.5
ns
Propagation Delay
Note 1
2.2
3
5
ns
Output to Output Skew
Note 2
Rising edges at VDD/2
0
250
ps
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Units
Input Frequency
0
200
MHz
Output Rise Time
t
OR
0.7 V to 1.7 V
1.0
1.5
ns
Output Fall Time
t
OF
1.7 V to 0.7 V
1.0
1.5
ns
Propagation Delay
Note 1
2.2
3
5
ns
Output to Output Skew
Note 2
Rising edges at VDD/2
0
250
ps
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Units
Thermal Resistance Junction to
Ambient
JA
Still air
150
C/W
JA
1 m/s air flow
140
C/W
JA
3 m/s air flow
120
C/W
Thermal Resistance Junction to Case
JC
40
C/W
L
OW
S
KEW
1
TO
4 C
LOCK
B
UFFER
MDS 651 C
6
Revision 120805
I n t e gr a t e d C i r c u i t S y s t e m s
5 2 5 R a c e S t r e e t , S a n J o s e, C A 9 5 1 2 6
t e l ( 4 0 8 ) 2 9 7 - 1 2 0 1
w w w. i c s t . c o m
ICS651
Package Outline and Package Dimensions
(8-pin SOIC, 150 Mil. Narrow Body)
Package dimensions are kept current with JEDEC Publication No. 95
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 Circuit Systems (ICS)
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.
Part / Order Number
Marking
Shipping Packaging
Package
Temperature
ICS651MI
ICS651MI
Tubes
8-pin SOIC
-40 to +85
C
ICS651MIT
ICS651MI
Tape and Reel
8-pin SOIC
-40 to +85
C
ICS651MILF
651MILF
Tubes
8-pin SOIC
-40 to +85
C
ICS651MILFT
651MILF
Tape and Reel
8-pin SOIC
-40 to +85
C
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
0.33
0.51
.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
0.25
0.50
.010
.020
L
0.40
1.27
.016
.050
0
8
0
8
L
OW
S
KEW
1
TO
4 C
LOCK
B
UFFER
MDS 651 C
7
Revision 120805
I n t e gr a t e d C i r c u i t S y s t e m s
5 2 5 R a c e S t r e e t , S a n J o s e, C A 9 5 1 2 6
t e l ( 4 0 8 ) 2 9 7 - 1 2 0 1
w w w. i c s t . c o m
ICS651
Revision History
Rev.
Originator
Date
Description of Change
A
K. Beckmeyer
6/27/05
Preliminary Datasheet
B
K. Beckmeyer
8/31/05
Output high and low voltage current conditions changed to 6mA and 6mA respectively at
1.8V, and -8mA and 8mA respectively at 2.5V operation. Short circuit current spec
changed to 50mA typical at 2.5V operation. Output-to-output skew max spec changed to
250ps at both 1.8V and 2.5V operation.
C
K. Beckmeyer
12/08/05
Added LF ordering info.
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