ICS8634-01
1-
TO
-5 D
IFFERENTIAL
-
TO
-3.3V LVPECL
Z
ERO
D
ELAY
B
UFFER
PRODUCT DISCONTINUATION NOTICE - LAST TIME BUY EXPIRES 4/25/2015
G
ENERAL
D
ESCRIPTION
The ICS8634-01 is a high performance 1-to-5 Differen-
tial-to-3.3V LVPECL Zero Delay Buffer. The ICS8634-01 has
two selectable clock inputs. The CLKx, nCLKx pair can accept
most standard differential input levels. Utilizing one of the out-
puts as feedback to the PLL, output frequencies up to 700MHz
can be regenerated with zero delay with respect to the input.
Dual reference clock inputs support redundant clock or multiple
reference applications.
F
EATURES
•
Five differential 3.3V LVPECL outputs
•
Selectable differential clock inputs
•
CLKx, nCLKx pair can accept the following differential
input levels: LVPECL, LVDS, LVHSTL, HCSL, SSTL
•
Output frequency range: 31.25MHz to 700MHz
•
Input frequency range: 31.25MHz to 700MHz
•
VCO range: 250MHz to 700MHz
•
External feedback for “zero delay” clock regeneration
•
Cycle-to-cycle jitter: 25ps (maximum)
•
Output skew: 25ps (maximum)
•
PLL reference zero delay: 50ps ± 100ps
•
3.3V operating supply
•
0°C to 70°C ambient operating temperature
•
Lead-Free package available
•
Industrial temperature information available upon request
•
Functional replacement parts; 8735AY-31LF,
8735BYI-01LF or 8735BKI-01LF
B
LOCK
D
IAGRAM
Q0
nQ0
PLL_SEL
÷4, ÷8
CLK0
nCLK0
CLK1
nCLK1
CLK_SEL
FB_IN
nFB_IN
0
1
1
0
Q1
nQ1
Q2
nQ2
Q3
nQ3
P
IN
A
SSIGNMENT
PLL_SEL
V
CCO
V
CCA
nQ4
V
CC
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16
V
CC
nFB_IN
FB_IN
V
EE
V
EE
nQ0
Q0
V
CCO
V
EE
V
EE
Q4
32 31 30 29 28 27 26 25
SEL0
SEL1
CLK0
nCLK0
CLK1
nCLK1
CLK_SEL
MR
24
23
22
V
CCO
Q3
nQ3
Q2
nQ2
Q1
nQ1
V
CCO
PLL
Q4
nQ4
ICS8634-01
21
20
19
18
17
SEL0
SEL1
MR
32-Lead LQFP
7mm x 7mm x 1.4mm package body
Y Package
Top View
32-Lead VFQFN
5mm x 5mm x 0.95 package body
K Package
Top View
8634BY-01
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REV. D MAY 12, 2014
1
ICS8634-01
1-
TO
-5 D
IFFERENTIAL
-
TO
-3.3V LVPECL
Z
ERO
D
ELAY
B
UFFER
T
ABLE
1. P
IN
D
ESCRIPTIONS
Number
1
2
3
4
5
6
7
8
9, 32
10
V
CC
nFB_IN
Name
SEL0
SEL1
CLK0
nCLK0
CLK1
nCLK1
CLK_SEL
MR
Input
Input
Input
Input
Input
Input
Input
Input
Power
Input
Input
Power
Output
Power
Output
Output
Output
Output
Power
Type
Description
Pulldown Determines output divider values in Table 3. LVCMOS / LVTTL interface levels.
Pulldown Determines output divider values in Table 3. LVCMOS / LVTTL interface levels.
Pulldown Non-inverting differential clock input.
Pullup
Pullup
Inverting differential clock input.
Pulldown Non-inverting differential clock input.
Inverting differential clock input.
Clock select input. When LOW, selects CLK0, nCLK0.
Pulldown
When HIGH, selects CLK1, nCLK1. LVCMOS / LVTTL interface levels.
Active High Master Reset. When logic HIGH, the internal dividers are reset caus-
ing the true outputs Qx to go low and the inverted outputs nQx to go
Pulldown
high. When logic LOW, the internal dividers and the outputs are enabled.
LVCMOS / LVTTL interface levels.
Core supply pins.
Pullup
Feedback input to phase detector for regenerating clocks with “zero delay”.
Negative supply pins.
Differential output pair. LVPECL interface levels.
Output supply pins.
Differential output pair. LVPECL interface levels.
Differential output pair. LVPECL interface levels.
Differential output pair. LVPECL interface levels..
Differential output pair. LVPECL interface levels.
Pulldown Feedback input to phase detector for regenerating clocks with “zero delay”.
11
FB_IN
12, 13
V
EE
28, 29
14, 15
nQ0, Q0
16. 17,
V
CCO
24, 25
18, 19
nQ1, Q1
20, 21
22, 23
26, 27
30
nQ2, Q2
nQ3, Q3
nQ4, Q4
V
CCA
Analog supply pin.
Selects between the PLL and the reference clock as the input to the dividers.
31
PLL_SEL
Input
Pullup When HIGH, selects PLL. When LOW, selects reference clock. LVCMOS / LVTTL
interface levels.
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
T
ABLE
3A. C
ONTROL
I
NPUT
F
UNCTION
T
ABLE
Inputs
SEL1
0
0
1
1
SEL0
0
1
0
1
Reference Frequency Range (MHz)*
250 - 700
125 - 350
62.5 - 175
31.25 - 87.5
Outputs
PLL_SEL = 1
PLL Enable Mode
Q0:Q4, nQ0:nQ4
÷1
÷1
÷1
÷1
T
ABLE
3B. PLL B
YPASS
F
UNCTION
T
ABLE
Inputs
SEL1
0
0
1
1
SEL0
0
1
0
1
Outputs
PLL_SEL = 0
PLL Bypass Mode
Q0:Q4, nQ0:nQ4
÷4
÷4
÷4
÷8
*NOTE: VCO frequency range for all configurations above is
250MHz to 700MHz.
8634BY-01
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2
REV. D MAY 12, 2014
ICS8634-01
1-
TO
-5 D
IFFERENTIAL
-
TO
-3.3V LVPECL
Z
ERO
D
ELAY
B
UFFER
A
BSOLUTE
M
AXIMUM
R
ATINGS
Supply Voltage, V
CC
Inputs, V
I
Outputs, I
O
Continuous Current
Surge Current
4.6V
-0.5V to V
CC
+ 0.5V
50mA
100mA
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
beyond those listed in the
DC Characteristics
or
AC Charac-
teristics
is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect product reliability.
Package Thermal Impedance,
θ
JA
32 Lead LQFP
47.9°C/W (0 lfpm)
32 Lead VFQFN
34.8°C/W (0 lfpm)
Storage Temperature, T
STG
-65°C to 150°C
T
ABLE
4A. P
OWER
S
UPPLY
DC C
HARACTERISTICS
,
V
CC
= V
CCA
= V
CCO
= 3.3V±5%, T
A
= 0°C
TO
70°C
Symbol
V
CC
V
CCA
V
CCO
I
EE
I
CCA
Parameter
Core Supply Voltage
Analog Supply Voltage
Output Supply Voltage
Power Supply Current
Analog Supply Current
Test Conditions
Minimum
3.135
3.135
3.135
Typical
3.3
3.3
3.3
Maximum
3.465
3.465
3.465
150
15
Units
V
V
V
mA
mA
T
ABLE
4B. LVCMOS/LVTTL DC C
HARACTERISTICS
,
V
CC
= V
CCA
= V
CCO
= 3.3V±5%, T
A
= 0°C
TO
70°C
Symbol
V
IH
V
IL
I
IH
Parameter
Input High Voltage
Input Low Voltage
Input High Current
SEL0, SEL1,
CLK_SEL, MR
PLL_SEL
I
IL
Input Low Current
SEL0, SEL1,
CLK_SEL, MR
PLL_SEL
V
CC
= V
IN
= 3.465V
V
CC
= V
IN
= 3.465V
V
CC
= 3.465V, V
IN
= 0V
V
CC
= 3.465V, V
IN
= 0V
-5
-150
Test Conditions
Minimum
2
-0.3
Typical
Maximum
V
CC
+ 0.3
0.8
150
5
Units
V
V
µA
µA
µA
µA
T
ABLE
4C. D
IFFERENTIAL
DC C
HARACTERISTICS
,
V
CC
= V
CCA
= V
CCO
= 3.3V±5%, T
A
= 0°C
TO
70°C
Symbol
I
IH
I
IL
V
PP
V
CMR
Parameter
Input High Current
Input Low Current
CLK0, CLK1, FB_IN
nCLK0, nCLK1, nFB_IN
CLK0, CLK1, FB_IN
nCLK0, nCLK1, nFB_IN
Test Conditions
V
CC
= V
IN
= 3.465V
V
CC
= V
IN
= 3.465V
V
CC
= 3.465V, V
IN
= 0V
V
CC
= 3.465V, V
IN
= 0V
-5
-150
0.15
V
EE
+ 0.5
1.3
V
CC
- 0.85
Minimum
Typical
Maximum
150
5
Units
µA
µA
µA
µA
V
V
Peak-to-Peak Input Voltage
Common Mode Input Voltage; NOTE 1, 2
NOTE 1: For single ended applications, the maximum input voltage for CLK0, nCLK0 and CLK1, nCLK1 is V
CC
+ 0.3V.
NOTE 2: Common mode voltage is defined as V
IH
.
8634BY-01
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REV. D MAY 12, 2014
3
ICS8634-01
1-
TO
-5 D
IFFERENTIAL
-
TO
-3.3V LVPECL
Z
ERO
D
ELAY
B
UFFER
T
ABLE
4D. LVPECL DC C
HARACTERISTICS
,
V
CC
= V
CCA
= V
CCO
= 3.3V±5%, T
A
= 0°C
TO
70°C
Symbol
V
OH
V
OL
V
SWING
Parameter
Output High Voltage; NOTE 1
Output Low Voltage; NOTE 1
Peak-to-Peak Output Voltage Swing
Test Conditions
Minimum
V
CCO
- 1.4
V
CCO
- 2.0
0.6
Typical
Maximum
V
CCO
- 0.7
V
CCO
- 1.7
1.0
Units
V
V
V
NOTE 1: Outputs terminated with 50Ω to V
CCO
- 2V.
T
ABLE
5. I
NPUT
F
REQUENCY
C
HARACTERISTICS
,
V
CC
= V
CCA
= V
CCO
= 3.3V±5%, T
A
= 0°C
TO
70°C
Symbol
f
IN
Parameter
Input Frequency
CLK0, nCLK0,
CLK1, nCLK1
Test Conditions
PLL_SEL = 1
PLL_SEL = 0
Minimum
31.25
Typical
Maximum
700
700
Units
MHz
MHz
T
ABLE
6. AC C
HARACTERISTICS
,
V
CC
= V
CCA
= V
CCO
= 3.3V±5%, T
A
= 0°C
TO
70°C
Symbol
f
MAX
t
PD
t(Ø)
tsk(o)
tjit(cc)
tjit(θ)
t
L
t
R
/ t
F
odc
Parameter
Output Frequency
Propagation Delay; NOTE 1
PLL Reference Zero Delay;
NOTE 2, 4
Output Skew; NOTE 3, 4
Cycle-to-Cycle Jitter; NOTE 4, 6
Phase Jitter; NOTE 4, 5, 6
PLL Lock Time
Output Rise/Fall Time
Output Duty Cycle
20% to 80% @ 50MHz
300
47
PLL_SEL = 0V,
f
≤
700MHz
PLL_SEL = 3.3V
3.2
-50
50
Test Conditions
Minimum
Typical
Maximum
700
4.2
150
25
25
±50
1
700
53
Units
MHz
ns
ps
ps
ps
ps
ms
ps
%
All parameters measured at f
MAX
unless noted otherwise.
NOTE 1: Measured from the differential input crossing point to the differential output crossing point.
NOTE 2: Defined as the time difference between the input reference clock and the average feedback input signal
when the PLL is locked and the input reference frequency is stable.
NOTE 3: Defined as skew between outputs at the same supply voltage and with equal load conditions.
Measured at the output differential cross points.
NOTE 4: This parameter is defined in accordance with JEDEC Standard 65.
NOTE 5: Phase jitter is dependent on the input source used.
NOTE 6: Characterized at VCO frequency of 622MHz.
8634BY-01
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4
REV. D MAY 12, 2014
ICS8634-01
1-
TO
-5 D
IFFERENTIAL
-
TO
-3.3V LVPECL
Z
ERO
D
ELAY
B
UFFER
P
ARAMETER
M
EASUREMENT
I
NFORMATION
3.3V O
UTPUT
L
OAD
AC T
EST
C
IRCUIT
D
IFFERENTIAL
I
NPUT
L
EVEL
O
UTPUT
S
KEW
C
YCLE
-
TO
-C
YCLE
J
ITTER
O
UTPUT
R
ISE
/F
ALL
T
IME
O
UTPUT
D
UTY
C
YCLE
/PU
LSE
W
IDTH
/P
ERIOD
P
ROPAGATION
D
ELAY
8634BY-01
P
HASE
J
ITTER
& S
TATIC
P
HASE
O
FFSET
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REV. D MAY 12, 2014
5