FemtoClock
®
680MHz Crystal-to-3.3V
Differential LVPECL Frequency Synthesizer
PRODUCT DISCONTINUATION NOTICE - LAST TIME BUY EXPIRES MAY 6, 2017
843202I
DATA SHEET
G
ENERAL
D
ESCRIPTION
The 843202I is a 2 output LVPECL Synthesizer optimized to generate
Gigabit Ethernet and SONET reference clock frequencies and is
a member of the family of high performance clock solutions from
IDT. Using a 19.44MHz and 25MHz, 18pF parallel resonant crystal,
155.52MHz and 156.25MHz frequencies can be generated. The part
also allows the use of a recovered clock at QB output. The 843202I
uses IDT’s FemtoClock
TM
low phase noise VCO technology and can
achieve 1ps or lower typical RMS phase jitter. The 843202I is
packaged in a 32-pin LQFP package.
F
EATURES
• Two 3.3V LVPECL outputs
• Selectable crystal oscillator interface or one differential recov-
ered clock inputs
• Supports the following output frequencies: 155.52MHz and
156.25MHz
• VCO range: 560MHz - 680MHz
• RMS phase jitter @ 155.52MHz, using a 19.44MHz crystal
(12kHz – 1.3MHz): 0.86ps (typical)
• RMS phase jitter @ 156.25MHz, using a 25MHz crystal
(1.875MHz –- 20MHz): 0.56ps (typical)
• Full 3.3V supply mode
SELB
X
F
UNCTION
T
ABLE
Control Inputs
SEL[1:0]
00
01
10
11
Outputs
nQB, QB
High, Low
REC_CLK
156.25MHz driven by XTAL_0
155.52MHz driven by XTAL_1
• -40°C to 85°C ambient operating temperature
• Available in lead-free (RoHS 6) package
•
For functional replacement part use 8T49N242
B
LOCK
D
IAGRAM
OEA
Pullup
P
IN
A
SSIGNMENT
XTAL_OUT0
XTAL_IN0
nQA
25MHz
V
EE
QA
XTAL_IN0
XTAL_OUT0
OSC
Phase
Detector
VCO
625MHz
QA
nc
nc
nc
÷4
nQA
156.25MHz
32 31 30 29 28 27 26 25
V
CCO
_
A
nc
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16
nc
QB
nQB
nc
nc
nc
nc
V
CCA
24
23
22
21
20
19
18
17
OEA
V
CC
V
CCA
SEL0
V
EE
OEB
V
CC
SEL1
÷25
00
REC_CLK
Pulldown
nREC_CLK
Pullup
19.44MHz
XTAL_IN1
XTAL_OUT1
nc
01
10
OSC
Phase
Detector
VCO
622.08MHz
QB
nQB
REC_CLK
nREC_CLK
V
CCO
_
B
XTAL_IN1
XTAL_OUT1
÷4
155.52MHz
11
843202I
÷32
SEL[1:0]
Pullup
OEB
Pullup
32-Lead LQFP
7mm x 7mm x 1.4mm
package body
Y Package
Top View
843202I REVISION A 5/26/16
1
©2016 Integrated Device Technology, Inc.
843202I DATA SHEET
T
ABLE
1. P
IN
D
ESCRIPTIONS
Number
1
2, 5, 9, 12, 13,
14, 15, 26, 29, 32
3,
4
6
7
8
10, 11
16, 22
17, 21
18, 23
19
20, 25
24
27, 28
30, 31
Pullup
Name
V
CCO_A
nc
XTAL_IN1, XTAL_
OUT1
REC_CLK
nREC_CLK
V
CCO_B
QB, nQB
V
CCA
SEL1, SEL0
V
CC
OEB
V
EE
OEA
XTAL_OUT0,
XTAL_IN0
nQA, QA
Power
Type
Description
Output supply pin for Bank A output.
No connect.
Parallel resonant crystal interface. XTAL_OUT1 is the output,
XTAL_IN1 is the input.
Unused
Input
Input
Input
Power
Ouput
Power
Input
Power
Input
Power
Input
Input
Output
Pullup
Pullup
Pullup
Pulldown Non-inverting differential recovered clock inputs.
Pullup
Inverting differential recovered clock inputs.
Output supply pin for Bank B output.
Differential output pair. LVPECL interface levels.
Analog supply pins.
Select pins. See SELx Function Table.
LVCMOS/LVTTL interface levels.
Core supply pins.
Output enable pin. QB/nQB output is enabled.
LVCMOS/LVTTL interface levels.
Negative supply pins.
Output enable pin. QA/nQA output is enabled.
LVCMOS/LVTTL interface levels.
Parallel resonant crystal interface. XTAL_OUT0 is the output,
XTAL_IN0 is the input.
Differential output pair. LVPECL interface levels.
NOTE: refers 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
FEMTOCLOCK
®
680MHZ, CRYSTAL-TO-3.3V
DIFFERENTIAL LVPECL FREQUENCY SYNTHESIZER
2
REVISION A 5/26/16
843202I DATA SHEET
A
BSOLUTE
M
AXIMUM
R
ATINGS
Supply Voltage, V
CC
Inputs, V
I
Outputs, I
O
Continuous Current
Surge Current
Package Thermal Impedance,
θ
JA
Storage Temperature, T
STG
4.6V
-0.5V to V
CC
+ 0.5V
50mA
100mA
80.8°C/W (0 mps)
-65°C to 150°C
N OT E : S t r e s s e s b eyo n d t h o s e l i s t e d u n d e r A b s o l u t e
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 Characteristics
is not
implied. Exposure to absolute maximum rating conditions for ex-
tended periods may affect product reliability.
T
ABLE
3A. P
OWER
S
UPPLY
DC C
HARACTERISTICS
,
V
CC
= V
CCO_A
= V
CCO_B
= 3.3V±10%, T
A
= -40°C
TO
85°C
Symbol
V
CC
V
CCA
V
CCO_A,
V
CCO_B
I
EE
I
CCA
Parameter
Core Supply Voltage
Analog Supply Voltage
Output Supply Voltage
Power Supply Current
Analog Supply Current
Test Conditions
Minimum
2.97
V
CC
– 0.22
2.97
Typical
3.3
3.3
3.3
Maximum
3.63
V
CC
3.63
138
22
Units
V
V
V
mA
mA
T
ABLE
3B. LVCMOS / LVTTL DC C
HARACTERISTICS
,
V
CC
= V
CCO_A
= V
CCO_B
= 3.3V±10%, 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
OEA, OEB,
SEL0, SEL1
OEA, OEB,
SEL0, SEL1
VCC = VIN = 3.63V
Test Conditions
Minimum
2
-0.3
Typical
Maximum
V
CC
+ 0.3
0.8
5
Units
V
V
µA
µA
VCC = 3.63V, VIN = 0V
-150
T
ABLE
3C. D
IFFERENTIAL
DC C
HARACTERISTICS
,
V
CC
= V
CCO_A
= V
CCO_B
= 3.3V±10%, T
A
= -40°C
TO
85°C
Symbol
I
IH
I
IL
V
PP
V
CMR
Parameter
Input High Current
Input Low Current
REC_CLK
nREC_CLK
REC_CLK
nREC_CLK
Test Conditions
V
CC
= V
IN
= 3.465V
V
CC
= V
IN
= 3.465V
V
CC
= 3.63V, V
IN
= 0V
V
CC
= 3.63V, 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
NOTE 1: Common mode voltage is defined as V
IH
.
REVISION A 5/26/16
3
FEMTOCLOCK
®
680MHZ, CRYSTAL-TO-3.3V
DIFFERENTIAL LVPECL FREQUENCY SYNTHESIZER
843202I DATA SHEET
T
ABLE
3D. LVPECL DC C
HARACTERISTICS
,
V
CC
= V
CCO_A
= V
CCO_B
= 3.3V±10%, T
A
= -40°C
TO
85°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
- 0.9
V
CCO
- 1.7
1.0
Units
V
V
V
NOTE 1: Outputs terminated with 50Ω to V
CCO_A, _B
- 2V.
T
ABLE
4. C
RYSTAL
C
HARACTERISTICS
Parameter
Mode of Oscillation
Frequency
Equivalent Series Resistance (ESR)
Shunt Capacitance
Drive Level
NOTE: Characterized using an 18pF parallel resonant crystal.
19.44
Test Conditions
Minimum
Typical
Maximum
25
50
7
1
Units
MHz
Ω
pF
mW
Fundamental
T
ABLE
5. AC C
HARACTERISTICS
,
V
CC
= V
CCO_A
= V
CCO_B
= 3.3V±10%, T
A
= -40°C
TO
85°C
Symbol
f
OUT
tjit(Ø)
t
R
/ t
F
odc
Parameter
Output Frequency
QB/nQB
QA/nQA
RMS Phase Jitter (Random);
NOTE 1
Output Rise/Fall Time
Output Duty Cycle
155.52MHz, (12kHz - 1.3MHz)
156.25MHz, (1.875MHz - 20MHz)
PLL Mode, 20% to 80%
PLL Mode
300
49
Test Conditions
PLL Mode
Minimum
140
140
Typical
155.52
156.25
0.86
0.56
550
51
Maximum
170
170
Units
MHz
MHz
ps
ps
ps
%
All parameters measured up to 170MHz unless otherwise specified.
NOTE 1: See Phase Noise plots.
FEMTOCLOCK
®
680MHZ, CRYSTAL-TO-3.3V
DIFFERENTIAL LVPECL FREQUENCY SYNTHESIZER
4
REVISION A 5/26/16
843202I DATA SHEET
-10
-20
-30
-40
-50
-60
➤
Filter
155.52MHz
RMS Phase Jitter (Random)
12kHz to 1.3MHz = 0.86ps (typical)
0
T
YPICAL
P
HASE
N
OISE AT
155.52MH
Z
N
OISE
P
OWER
dBc
Hz
-70
-80
-90
-100
Raw Phase Noise Data
➤
-110
-120
-130
-140
-150
-160
-170
-180
-190
10
100
➤
Phase Noise Result by adding
a Filter to raw data
1k
10k
100k
1M
10M
100M
O
FFSET
F
REQUENCY
(H
Z
)
T
YPICAL
P
HASE
N
OISE AT
156.25MH
Z
-10
-20
-30
-40
-50
-60
-70
➤
Filter
156.25MHz
RMS Phase Jitter (Random)
1.875MHz to 20MHz = 0.56ps (typical)
0
N
OISE
P
OWER
dBc
Hz
-80
-90
-100
-110
-120
-130
-140
-150
-170
-180
-190
10
100
1k
10k
100k
1M
10M
100M
Raw Phase Noise Data
➤
➤
-160
Phase Noise Result by adding
a Filter to raw data
O
FFSET
F
REQUENCY
(H
Z
)
REVISION A 5/26/16
5
FEMTOCLOCK
®
680MHZ, CRYSTAL-TO-3.3V
DIFFERENTIAL LVPECL FREQUENCY SYNTHESIZER