Integrated
Circuit
Systems, Inc.
ICS8521I-03
L
OW
S
KEW
, 1-
TO
-9
D
IFFERENTIAL
-
TO
-LVHSTL F
ANOUT
B
UFFER
F
EATURES
•
9 LVHSTL outputs
•
Redundant differential CLK0, nCLK0 and CLK1, nCLK1 inputs
•
CLKx, nCLKx pairs can accept the following differential
input levels: LVPECL, LVDS, LVHSTL, SSTL, HCSL
•
Maximum output frequency: 500MHz
•
Output skew: 50ps (maximum)
•
Part-to-part skew: 250ps (maximum)
•
Propagation delay: 1.6ns (maximum)
•
V
OH
= 1V (maximum)
•
3.3V core, 1.8V output operating supply voltages
•
-40°C to 85°C ambient operating temperature
G
ENERAL
D
ESCRIPTION
The ICS8521I-03 is a low skew, 1-to-9 Differen-
tial-to-LVHSTL Fanout Buffer and a member of
HiPerClockS™
the HiPerClockS™ family of High Performance
Clock Solutions from ICS. The ICS8521I-03 has
two selectable clock inputs. Redundant clock
pairs, CLK0, nCLK0 and CLK1, nCLK1 can accept most stan-
dard differential input levels. The clock enable is internally syn-
chronized to eliminate runt pulses on the outputs during asyn-
chronous assertion/deassertion of the clock enable pin.
,&6
Guaranteed output skew and part-to-part skew characteris-
tics make the ICS8521I-03 ideal for today’s most advanced
applications, such as IA64 and static RAMs.
B
LOCK
D
IAGRAM
CLK_EN
CLK0
nCLK0
CLK1
nCLK1
CLK_SEL
D
Q
LE
0
1
Q0
nQ0
Q1
nQ1
Q2
nQ2
Q3
nQ3
Q4
nQ4
Q5
nQ5
Q6
nQ6
Q7
nQ7
Q8
nQ8
P
IN
A
SSIGNMENT
V
DDO
V
DDO
nQ2
Q2
nQ1
Q1
nQ0
Q0
32 31 30 29 28 27 26 25
V
DD
CLK0
nCLK0
CLK_SEL
CLK1
nCLK1
GND
CLK_EN
1
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
9 1 0 1 1 1 2 1 3 1 4 1 5 16
V
DDO
Q6
nQ6
Q7
nQ7
Q8
nQ8
V
DDO
V
DDO
Q3
nQ3
Q4
nQ4
Q5
nQ5
V
DDO
ICS8521I-03
32-Lead LQFP
7mm x 7mm x 1.4mm Package Body
Y Package
Top View
8521AYI-03
www.icst.com/products/hiperclocks.html
1
REV. A APRIL 29, 2003
Integrated
Circuit
Systems, Inc.
ICS8521I-03
L
OW
S
KEW
, 1-
TO
-9
D
IFFERENTIAL
-
TO
-LVHSTL F
ANOUT
B
UFFER
Type
Power
Input
Input
Input
Input
Input
Power
Input
Power
Output
Output
Output
Output
Output
Output
Output
Output
Output
Pullup
Pulldown
Pullup
Pulldown
Pulldown
Pullup
Description
Core supply pin.
Non-inver ting differential clock input.
Inver ting differential clock input.
Clock select input. When HIGH, selects CLK1, nCLK1 inputs.
When LOW, selects CLK0, nCLK0.
LVTTL / LVCMOS interface levels.
Non-inver ting differential clock input.
Inver ting differential clock input.
Power supply ground.
Synchronizing clock enable. When HIGH, clock outputs follow
clock input. When LOW, Q outputs are forced low, nQ outputs
are forced high. LVCMOS /LVTTL interface levels.
Output supply pins.
Differential output pair. LVHSTL interface level.
Differential output pair. LVHSTL interface level.
Differential output pair. LVHSTL interface level.
Differential output pair. LVHSTL interface level.
Differential output pair. LVHSTL interface level.
Differential output pair. LVHSTL interface level.
Differential output pair. LVHSTL interface level.
Differential output pair. LVHSTL interface level.
Differential output pair. LVHSTL interface level.
T
ABLE
1. P
IN
D
ESCRIPTIONS
Number
1
2
3
4
5
6
7
8
9, 16, 17,
24, 25, 32
10, 11
12, 13
14, 15
18, 19
20, 21
22, 23
26, 27
28, 29
30, 31
Name
V
DD
CLK0
nCLK0
CLK_SEL
CLK1
nCLK1
GND
CLK_EN
V
DDO
nQ8, Q8
nQ7, Q7
nQ6, Q6
nQ5, Q5
nQ4, Q4
nQ3, Q3
nQ2, Q2
nQ1, Q1
nQ0, Q0
NOTE:
Pullup
and
Pulldown
refer to internal input resistors. See Table 2, Pin Characteristics, for typical values.
T
ABLE
2. P
IN
C
HARACTERISTICS
Symbol
C
IN
R
PULLUP
R
PULLDOWN
Parameter
Input Capacitance
Input Pullup Resistor
Input Pulldown Resistor
Test Conditions
Minimum Typical
4
51
51
Maximum Units
pF
KΩ
KΩ
8521AYI-03
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2
REV. A APRIL 29, 2003
Integrated
Circuit
Systems, Inc.
ICS8521I-03
L
OW
S
KEW
, 1-
TO
-9
D
IFFERENTIAL
-
TO
-LVHSTL F
ANOUT
B
UFFER
Inputs
Outputs
Selected Sourced
CLK0, nCLK0
CLK1, nCLK1
CLK0, nCLK0
Q0:Q8
Disabled; LOW
Disabled; LOW
Enabled
nQ0:nQ8
Disabled; HIGH
Disabled; HIGH
Enabled
T
ABLE
3A. C
ONTROL
I
NPUT
F
UNCTION
T
ABLE
CLK_EN
0
0
1
CLK_SEL
0
1
0
1
1
CLK1, nCLK1
Enabled
Enabled
After CLK_EN switches, the clock outputs are disabled or enabled following a rising and falling input clock edge
as shown in
Figure 1
.
In the active mode, the state of the outputs are a function of the CLKx, nCLKx inputs as described
in
Table 3B.
Disabled
nCLK0, CLK1
CLK0, CLK1
Enabled
CLK_EN
nQ0:nQ8
Q0:Q8
F
IGURE
1. CLK_EN T
IMING
D
IAGRAM
T
ABLE
3B. C
LOCK
I
NPUT
F
UNCTION
T
ABLE
Inputs
CLK0 or CLK1
0
1
0
1
Biased; NOTE 1
Biased; NOTE 1
nCLK0 or nCLK1
1
0
Biased; NOTE 1
Biased; NOTE 1
0
1
Q0:Q8
LOW
HIGH
LOW
HIGH
HIGH
LOW
Outputs
nQ0:nQ8
HIGH
LOW
HIGH
LOW
LOW
HIGH
Input to Output Mode
Differential to Differential
Differential to Differential
Single Ended to Differential
Single Ended to Differential
Single Ended to Differential
Single Ended to Differential
Polarity
Non Inver ting
Non Inver ting
Non Inver ting
Non Inver ting
Inver ting
Inver ting
NOTE 1: Please refer to the Application Information "Wiring the Differential Input to Accept Single Ended Levels".
8521AYI-03
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3
REV. A APRIL 29, 2003
Integrated
Circuit
Systems, Inc.
ICS8521I-03
L
OW
S
KEW
, 1-
TO
-9
D
IFFERENTIAL
-
TO
-LVHSTL F
ANOUT
B
UFFER
4.6V
-0.5V to V
DD
+ 0.5 V
-0.5V to V
DDO
+ 0.5V
47.9°C/W (0 lfpm)
-65°C to 150°C
NOTE: Stresses beyond those listed under Absolute
Maximum Ratings may cause permanent damage to the
device. These ratings are stress specifications only. Functional
operation of product at these conditions or any conditions be-
yond those listed in the
DC Characteristics
or
AC Character-
istics
is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect product reliability.
A
BSOLUTE
M
AXIMUM
R
ATINGS
Supply Voltage, V
DD
Inputs, V
I
Outputs, V
O
Package Thermal Impedance,
θ
JA
Storage Temperature, T
STG
T
ABLE
4A. P
OWER
S
UPPLY
DC C
HARACTERISTICS
,
V
DD
= 3.3V±5%, V
DDO
= 1.8V±0.2V, T
A
= -40°C
TO
85°C
Symbol
V
DD
V
DDO
I
DD
Parameter
Core Supply Voltage
Output Supply Voltage
Power Supply Current
Test Conditions
Minimum
3.135
1.6
Typical
3.3
1.8
Maximum
3.465
2.0
95
Units
V
V
mA
T
ABLE
4B. LVCMOS/LVTTL DC C
HARACTERISTICS
,
V
DD
= 3.3V±5%, V
DDO
= 1.8V±0.2V, T
A
= -40°C
TO
85°C
Symbol
V
IH
V
IL
I
IH
I
IL
Parameter
Input High Voltage
Input Low Voltage
Input High Current
Input Low Current
CLK_EN
CLK_SEL
CLK_EN
CLK_SEL
V
IN
= V
DD
= 3.465V
V
IN
= V
DD
= 3.465V
V
IN
= 0V, V
DD
= 3.465V
V
IN
= 0V, V
DD
= 3.465V
-150
-5
Test Conditions
Minimum
2
-0.3
Typical
Maximum
V
DD
+ 0.3
0.8
5
150
Units
V
V
µA
µA
µA
µA
T
ABLE
4C. D
IFFERENTIAL
DC C
HARACTERISTICS
,
V
DD
= 3.3V±5%, V
DDO
= 1.8V±0.2V, T
A
= -40°C
TO
85°C
Symbol
I
IH
I
IL
V
PP
Parameter
Input High Current
Input Low Current
CLKx
nCLKx
CLKx
nCLKx
Test Conditions
V
IN
= V
DD
= 3.465V
V
IN
= V
DD
= 3.465V
V
IN
= 0V, V
DD
= 3.465V
V
IN
= 0V, V
DD
= 3.465V
-5
-150
1.3
V
DD
- 0.85
Minimum
Typical
Maximum
150
5
Units
µA
µA
µA
µA
V
V
Peak-to-Peak Input Voltage
0.15
Common Mode Input Voltage;
V
CMR
0.5
NOTE 1, 2
NOTE 1: For single ended applications, the maximum input voltage for CLKx and nCLKx is V
DD
+ 0.3V.
NOTE 2: Common mode voltage is defined as V
IH
.
8521AYI-03
www.icst.com/products/hiperclocks.html
4
REV. A APRIL 29, 2003
Integrated
Circuit
Systems, Inc.
ICS8521I-03
L
OW
S
KEW
, 1-
TO
-9
D
IFFERENTIAL
-
TO
-LVHSTL F
ANOUT
B
UFFER
Test Conditions
Minimum
0.7
0
0.4
Typical
Maximum
1.0
0.4
1.0
Units
V
V
V
T
ABLE
4D. LVHSTL DC C
HARACTERISTICS
,
V
DD
= 3.3V±5%, V
DDO
= 1.8V±0.2V, T
A
= -40°C
TO
85°C
Symbol Parameter
V
OH
V
OL
V
SWING
Output High Voltage; NOTE 1
Output Low Voltage; NOTE 1
Peak-to-Peak Output Voltage Swing
NOTE 1: Outputs terminated with 50
Ω
to ground.
T
ABLE
5. AC C
HARACTERISTICS
,
V
DD
= 3.3V±5%, V
DDO
= 1.8V±0.2V, T
A
= -40°C
TO
85°C
Symbol
f
MAX
t
PD
Parameter
Output Frequency
Propagation Delay; NOTE 1
Output Skew; NOTE 2, 4
Par t-to-Par t Skew; NOTE 3, 4
Output Rise/Fall Time
Output Duty Cycle
IJ 266MHz
200
48
1.0
Test Conditions
Minimum
Typical
Maximum
500
1.6
50
250
700
52
55
Units
MHz
ns
ps
ps
ps
%
%
t
sk(o)
t
sk(pp)
t
R
/ t
F
odc
266MHz < ƒ
≤
500MHz
45
NOTE 1: Measured from the differential input crossing point to the differential output crossing point.
NOTE 2: Defined as skew between outputs at the same supply voltage and with equal load conditions.
Measured at the output differential cross points.
NOTE 3: Defined as skew between outputs on different devices operating at the same supply voltages
and with equal load conditions. Using the same type of inputs on each device, the outputs are measured
at the differential cross points.
NOTE 4: This parameter is defined in accordance with JEDEC Standard 65.
8521AYI-03
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5
REV. A APRIL 29, 2003