ICST ICS843246AMT Femtoclocksâ ¢ crystal-to-3.3v lvpecl frequency synthesizer w/integrated fanout buffer Datasheet

PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
GENERAL DESCRIPTION
FEATURES
The ICS843246 is a Crystal-to-3.3V LVPECL
Clock Synthesizer/Fanout Buffer designed for
HiPerClockS™
Fibre Channel and Gigabit Ethernet applications and is a member of the HiperClockS™
family of High Performance Clock Solutions
from ICS. The output frequency can be set using the frequency select pins and a 25MHz crystal for Ethernet
frequencies, or a 26.5625MHz crystal for a Fibre Channel.
The low phase noise characteristics of the ICS843246
make it an ideal clock for these demanding applications.
• Six LVPECL outputs
ICS
• Crystal oscillator interface
• Output frequency range: 53.125MHz to 333.3333MHz
• Crystal input frequency range: 25MHz to 33.333MHz
• RMS phase jitter at 125MHz, using a 25MHz crystal
(1.875MHz to 20MHz): 0.41ps (typical)
• Full 3.3V or 3.3V core, 2.5V output supply mode
• 0°C to 70°C ambient operating temperature
• Industrial temperature information available upon request
• Available in both standard and lead-free RoHS-compliant
packages
SELECT FUNCTION TABLE
Inputs
Function
FB_SEL
N_SEL1
N_SEL0
M Divide
N Divide
M/N
0
0
0
20
2
10
0
0
1
20
4
5
0
1
0
20
5
4
0
1
1
20
8
2.5
1
0
0
24
3
8
1
0
1
24
4
6
1
1
0
24
6
4
1
1
1
24
12
2
BLOCK DIAGRAM
PIN ASSIGNMENT
Q0
nQ0
PLL_BYPASS
Pullup
Q1
1
XTAL_IN
OSC
PLL
nQ1
Output
Divider
0
XTAL_OUT
Q2
nQ2
Q3
Feedback
Divider
nQ3
FB_SEL
Pulldown
Q4
N_SEL1
Pullup
nQ4
N_SEL0
Pullup
Q5
nQ5
VCCO
VCCO
nQ2
Q2
nQ1
Q1
nQ0
Q0
PLL_BYPASS
V CCA
VCC
FB_SEL
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
Q3
nQ3
Q4
nQ4
Q5
nQ5
N_SEL1
V EE
V EE
N_SEL0
XTAL_OUT
XTAL_IN
ICS843246
24-Lead, 300-MIL SOIC
7.5mm x 15.33mm x 2.3mm
body package
M Package
Top View
24-Lead TSSOP
4.40mm x 7.8mm x 0.92mm
body package
G Package
Top View
The Preliminary Information presented herein represents a product in prototyping or pre-production. The noted characteristics are based on
initial product characterization. Integrated Circuit Systems, Incorporated (ICS) reserves the right to change any circuitry or specifications
without notice.
843246AM
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REV. A SEPTEMBER 29, 2005
1
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
TABLE 1. PIN DESCRIPTIONS
Number
Name
1, 2
VCCO
3, 4
5, 6
Type
Description
Power
Output supply pins.
nQ2, Q2
Output
Differential output pair. LVPECL interface levels.
nQ1, Q1
Output
Differential output pair. LVPECL interface levels.
7, 8
nQ0, Q0
Output
9
PLL_BYPASS
Input
10
VCCA
Power
Differential output pair. LVPECL interface levels.
Selects between the PLL and crystal inputs as the input to the dividers.
When LOW, selects PLL. When HIGH, selects XTAL_IN, XTAL_OUT.
LVCMOS / LVTTL interface levels.
Analog supply pin.
11
VCC
Power
Core supply pin.
12
13,
14
15,
18
16, 17
FB_SEL
XTAL_IN,
XTAL_OUT
N_SEL0
N_SEL1
VEE
Input
19, 20
nQ5, Q5
Output
21, 22
nQ4, Q4
Output
Differential output pair. LVPECL interface levels.
23, 24
nQ3, Q3
Output
Differential output pair. LVPECL interface levels.
Input
Input
Pullup
Pulldown Feedback frequency select pin. LVCMOS/LVTTL interface levels.
Crystal oscillator interface. XTAL_IN is the input.
XTAL_OUT is the output.
Pullup
Output frequency select pin. LVCMOS/LVTTL interface levels.
Negative supply pin.
Differential output pair. LVPECL interface levels.
NOTE: Pullup and Pulldown refer to internal input resistors. See Table 2, Pin Characteristics, for typical values.
TABLE 2. PIN CHARACTERISTICS
Symbol
Parameter
CIN
Input Capacitance
4
pF
RPULLUP
Input Pullup Resistor
51
kΩ
RPULLDOWN
Input Pulldown Resistor
51
kΩ
843246AM
Test Conditions
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2
Minimum
Typical
Maximum
Units
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ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
TABLE 3. CRYSTAL FUNCTION TABLE
Inputs
XTAL (MHz)
FB_SEL
Function
N_SEL1
N_SEL0
M
VCO (MHz)
N
Output (MHz)
25
0
0
0
20
500
2
250
25
0
0
1
20
500
4
125
25
0
1
0
20
500
5
10 0
25
0
1
1
20
500
8
62.5
25
1
0
0
24
600
3
200
25
1
0
1
24
600
4
150
25
1
1
0
24
600
6
100
25
1
1
1
24
600
12
50
26.5625
0
1
0
20
531.25
5
106.25
26.5625
1
0
0
24
637.5
3
212.5
26.5625
1
0
1
24
637.5
4
159.375
26.5625
1
1
0
24
637.5
6
106.25
26.5625
1
1
1
24
637.5
12
53.125
30
0
0
0
20
600
2
300
30
0
0
1
20
600
4
150
30
0
1
0
20
600
5
12 0
30
0
1
1
20
600
8
75
31.25
0
0
0
20
625
2
312.5
31.25
0
0
1
20
62 5
4
156.25
31.25
0
1
0
20
62 5
5
12 5
31.25
0
1
1
20
625
8
78.125
33.3333
0
0
0
20
666.6667
2
333.3333
33.3333
0
0
1
20
666.6667
4
166.6667
33.3333
0
1
0
20
666.6667
5
133.3333
33.3333
0
1
1
20
666.6667
8
83.3333
843246AM
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3
REV. A SEPTEMBER 29, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VCC
4.6V
Inputs, VI
-0.5V to VCC + 0.5V
Outputs, IO
Continuous Current
Surge Current
50mA
100mA
Package Thermal Impedance, θJA
24 Lead SOIC
24 Lead TSSOP
50°C/W (0 lfpm)
70°C/W (0 mps)
Storage Temperature, TSTG
-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 beyond those listed in the DC Characteristics or AC Characteristics is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect product reliability.
TABLE 4A. POWER SUPPLY DC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol
Parameter
VCC
Core Supply Voltage
Test Conditions
Minimum
Typical
Maximum
Units
3.135
3. 3
3.465
V
VCCA
Analog Supply Voltage
3.135
3.3
3.465
V
VCCO
Output Supply Voltage
3.135
3.3
3.465
V
IEE
Power Supply Current
107
mA
ICCA
Analog Supply Current
7
mA
TABLE 4B. POWER SUPPLY DC CHARACTERISTICS, VCC = VCCA = 3.3V±5%, VCCO = 2.5V±5%, TA = 0°C TO 70°C
Symbol
Parameter
VCC
Core Supply Voltage
Test Conditions
Minimum
Typical
Maximum
Units
3.135
3.3
3.465
V
VCCA
Analog Supply Voltage
3.135
3.3
3.465
V
VCCO
Output Supply Voltage
2.375
2.5
2.625
V
IEE
Power Supply Current
107
mA
ICCA
Analog Supply Current
7
mA
TABLE 4C. LVCMOS / LVTTL DC CHARACTERISTICS, VCC = VCCA = 3.3V±5%, VCCO = 3.3V±5% OR 2.5V±5%, TA = 0°C TO 70°C
Symbol
Parameter
VIH
Input High Voltage
VIL
Input Low Voltage
IIH
Input High Current
IIL
Input Low Current
843246AM
Test Conditions
Minimum
2
-0.3
FB_SEL
PLL_BYPASS,
N_SEL0, N_SEL1
FB_SEL
PLL_BYPASS,
N_SEL0, N_SEL1
Typical
Maximum
Units
VCC + 0.3
V
0.8
V
VCC = VIN = 3.465V
150
µA
VCC = VIN = 3.465V
5
µA
VCC = 3.465V, VIN = 0V
-5
µA
VCC = 3.465V, VIN = 0V
-150
µA
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REV. A SEPTEMBER 29, 2005
PRELIMINARY
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ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
TABLE 4D. LVPECL DC CHARACTERISTICS, VCC = VCCA = 3.3V±5%, VCCO = 3.3V±5% OR 2.5V±5%, TA = 0°C TO 70°C
Symbol
Parameter
Test Conditions
VOH
Output High Voltage; NOTE 1
VOL
Output Low Voltage; NOTE 1
VSWING
Peak-to-Peak Output Voltage Swing
Minimum
Typical
Maximum
Units
VCCO - 1.4
VCCO - 0.9
V
VCCO - 2.0
VCCO - 1.7
V
0.6
1. 0
V
NOTE 1: Outputs terminated with 50Ω to VCCO - 2V.
TABLE 5. CRYSTAL CHARACTERISTICS
Parameter
Test Conditions
Minimum
Mode of Oscillation
Typical Maximum
Units
Fundamental
Frequency
25
33.333
MHz
Equivalent Series Resistance (ESR)
50
Ω
Shunt Capacitance
7
pF
Drive Level
1
mW
Maximum
Units
333.33
MHz
NOTE: Characterized using an 18pf parallel resonant crystal.
TABLE 6A. AC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol Parameter
FOUT
Test Conditions
Minimum
Output Frequency
t jit(Ø)
RMS Phase Jitter (Random)
t sk(o)
Output Skew; NOTE 1, 2
tR / tF
Output Rise/Fall Time
odc
Output Duty Cycle
Typical
53.125
125MHz, Integration Range:
1.875MHz - 20MHz
20% to 80%
0.41
ps
TBD
ps
380
ps
50
%
PLL Lock Time
tLOCK
See Parameter Measurement Information section.
NOTE 1: Defined as skew between outputs at the same supply voltage and with equal load conditions.
Measured at the output differential crossing points.
NOTE 2: This parameter is defined in accordance with JEDEC Standard 65.
1
ms
Maximum
Units
333.33
MHz
TABLE 6B. AC CHARACTERISTICS, VCC = VCCA = 3.3V±5%, VCCO = 2.5V±5%, TA = 0°C TO 70°C
Symbol Parameter
FOUT
Test Conditions
Minimum
Output Frequency
tjit(Ø)
RMS Phase Jitter (Random)
t sk(o)
Output Skew; NOTE 1, 2
tR / tF
Output Rise/Fall Time
odc
Output Duty Cycle
Typical
53.125
125MHz, Integration Range:
1.875MHz - 20MHz
20% to 80%
0.41
ps
TBD
ps
360
ps
50
PLL Lock Time
tLOCK
See Parameter Measurement Information section.
NOTE 1: Defined as skew between outputs at the same supply voltage and with equal load conditions.
Measured at the output differential crossing points.
NOTE 2: This parameter is defined in accordance with JEDEC Standard 65.
843246AM
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5
%
1
ms
REV. A SEPTEMBER 29, 2005
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Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
TYPICAL PHASE NOISE
AT
125MHZ @ 3.3V
➤
0
-10
-20
Gb Ethernet Filter
-30
-40
125MHz
-50
RMS Phase Jitter (Random)
1.875MHz to 20MHz = 0.41ps (typical)
-60
-70
-80
-90
-100
Raw Phase Noise Data
-110
➤
NOISE POWER dBc
Hz
ICS843246
-120
-130
-140
➤
-150
-160
Phase Noise Result by adding
Gb Ethernet Filter to raw data
-170
-180
-190
1k
10k
100k
1M
10M
100M
OFFSET FREQUENCY (HZ)
843246AM
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REV. A SEPTEMBER 29, 2005
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ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
PARAMETER MEASUREMENT INFORMATION
2.8V±0.04V
2V
2V
VCC,
VCCA, VCCO
Qx
SCOPE
VCC,
VCCA
Qx
SCOPE
VCCO
LVPECL
LVPECL
V EE
nQx
nQx
V EE
-1.3V ± 0.165V
-0.5V ± 0.125V
3.3V OUTPUT LOAD AC TEST CIRCUIT
3.3V/2.5V OUTPUT LOAD AC TEST CIRCUIT
nQx
nQ0:nQ5
Qx
Q0:Q5
t PW
t
nQy
Qy
odc =
tsk(o)
PERIOD
t PW
x 100%
t PERIOD
OUTPUT SKEW
OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD
80%
80%
VSW I N G
Clock
Outputs
20%
20%
tR
tF
OUTPUT RISE/FALL TIME
843246AM
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REV. A SEPTEMBER 29, 2005
PRELIMINARY
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ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
APPLICATION INFORMATION
POWER SUPPLY FILTERING TECHNIQUES
As in any high speed analog circuitry, the power supply pins
are vulnerable to random noise. The ICS843246 provides
separate power supplies to isolate any high switching
noise from the outputs to the internal PLL. VCC, VCCA and
VCCO should be individually connected to the power supply
plane through vias, and bypass capacitors should be used
for each pin. To achieve optimum jitter performance, power
supply isolation is required. Figure 1 illustrates how a 10Ω
resistor along with a 10μF and a .01μF bypass capacitor
should be connected to each V CCA pin. The 10Ω resistor
can also be replaced by a ferrite bead.
3.3V
VCC
.01μF
10Ω
V CCA
.01μF
10μF
FIGURE 1. POWER SUPPLY FILTERING
CRYSTAL INPUT INTERFACE
below were determined using an 18pF parallel resonant
crystal and were chosen to minimize the ppm error.
The ICS843246 has been characterized with 18pF parallel
resonant crystals. The capacitor values shown in Figure 2
XTAL_OUT
C1
22p
X1
18pF Parallel Crystal
XTAL_IN
C2
22p
Figure 2. CRYSTAL INPUt INTERFACE
843246AM
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REV. A SEPTEMBER 29, 2005
PRELIMINARY
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Systems, Inc.
ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
RECOMMENDATIONS FOR UNUSED INPUT AND OUTPUT PINS
INPUTS:
OUTPUTS:
LVPECL OUTPUT
All unused LVPECL outputs can be left floating. We
recommend that there is no trace attached. Both sides of the
differential output pair should either be left floating or
terminated.
LVCMOS CONTROL PINS:
All control pins have internal pull-ups or pull-downs; additional
resistance is not required but can be added for additional
protection. A 1kΩ resistor can be used.
TERMINATION FOR 3.3V LVPECL OUTPUT
The clock layout topology shown below is a typical termination for LVPECL outputs. The two different layouts mentioned are recommended only as guidelines.
designed to drive 50Ω transmission lines. Matched impedance techniques should be used to maximize operating
frequency and minimize signal distortion. Figures 3A and
3B show two different layouts which are recommended only
as guidelines. Other suitable clock layouts may exist and it
would be recommended that the board designers simulate to
guarantee compatibility across all printed circuit and clock
component process variations.
FOUT and nFOUT are low impedance follower outputs that
generate ECL/LVPECL compatible outputs. Therefore, terminating resistors (DC current path to ground) or current
sources must be used for functionality. These outputs are
3.3V
Zo = 50Ω
125Ω
FOUT
FIN
Zo = 50Ω
Zo = 50Ω
FOUT
50Ω
RTT =
1
Z
((VOH + VOL) / (VCC – 2)) – 2 o
FIN
50Ω
Zo = 50Ω
VCC - 2V
RTT
84Ω
FIGURE 3A. LVPECL OUTPUT TERMINATION
843246AM
125Ω
84Ω
FIGURE 3B. LVPECL OUTPUT TERMINATION
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REV. A SEPTEMBER 29, 2005
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FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
TERMINATION FOR 2.5V LVPECL OUTPUT
Figure 4A and Figure 4B show examples of termination for
2.5V LVPECL driver. These terminations are equivalent to
terminating 50Ω to VCC - 2V. For VCC = 2.5V, the VCC - 2V is very
close to ground level. The R3 in Figure 4B can be eliminated
and the termination is shown in Figure 4C.
2.5V
2.5V
2.5V
VCCO=2.5V
VCCO=2.5V
R1
250
R3
250
Zo = 50 Ohm
Zo = 50 Ohm
+
+
Zo = 50 Ohm
Zo = 50 Ohm
-
-
2,5V LVPECL
Driv er
2,5V LVPECL
Driv er
R2
62.5
R1
50
R4
62.5
R2
50
R3
18
FIGURE 4B. 2.5V LVPECL DRIVER TERMINATION EXAMPLE
FIGURE 4A. 2.5V LVPECL DRIVER TERMINATION EXAMPLE
2.5V
VCCO=2.5V
Zo = 50 Ohm
+
Zo = 50 Ohm
2,5V LVPECL
Driv er
R1
50
R2
50
FIGURE 4C. 2.5V LVPECL TERMINATION EXAMPLE
843246AM
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REV. A SEPTEMBER 29, 2005
PRELIMINARY
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FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
POWER CONSIDERATIONS
This section provides information on power dissipation and junction temperature for the ICS843246.
Equations and example calculations are also provided.
1. Power Dissipation.
The total power dissipation for the ICS843246 is the sum of the core power plus the power dissipated in the load(s).
The following is the power dissipation for VCC = 3.3V + 5% = 3.465V, which gives worst case results.
NOTE: Please refer to Section 3 for details on calculating power dissipated in the load.
•
•
Power (core)MAX = VCC_MAX * IEE_MAX = 3.465V * 107mA = 370.75mW
Power (outputs)MAX = 30.2mW/Loaded Output pair
If all outputs are loaded, the total power is 6 * 30mW = 180mW
Total Power_MAX (3.465V, with all outputs switching) = 370.75mW + 180mW = 550.75mW
2. Junction Temperature.
Junction temperature, Tj, is the temperature at the junction of the bond wire and bond pad and directly affects the reliability of the
device. The maximum recommended junction temperature for HiPerClockSTM devices is 125°C.
The equation for Tj is as follows: Tj = θJA * Pd_total + TA
Tj = Junction Temperature
θJA = Junction-to-Ambient Thermal Resistance
Pd_total = Total Device Power Dissipation (example calculation is in section 1 above)
TA = Ambient Temperature
In order to calculate junction temperature, the appropriate junction-to-ambient thermal resistance θJA must be used. Assuming a
moderate air flow of 200 linear feet per minute and a multi-layer board, the appropriate value is 43°C/W per Table 7 below.
Therefore, Tj for an ambient temperature of 70°C with all outputs switching is:
70°C + 0.551W * 43°C/W = 93.7°C. This is well below the limit of 125°C.
This calculation is only an example. Tj will obviously vary depending on the number of loaded outputs, supply voltage, air flow,
and the type of board (single layer or multi-layer).
TABLE 7. THERMAL RESISTANCE θJA FOR 24-PIN SOIC, FORCED CONVECTION
θJA by Velocity (Linear Feet per Minute)
Multi-Layer PCB, JEDEC Standard Test Boards
0
200
500
50°C/W
43°C/W
38°C/W
NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs.
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REV. A SEPTEMBER 29, 2005
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ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
3. Calculations and Equations.
The purpose of this section is to derive the power dissipated into the load.
LVPECL output driver circuit and termination are shown in Figure 5.
VCCO
Q1
VOUT
RL
50
VCCO - 2V
FIGURE 5. LVPECL DRIVER CIRCUIT AND TERMINATION
To calculate worst case power dissipation into the load, use the following equations which assume a 50Ω load, and a termination
voltage of V - 2V.
CCO
•
For logic high, VOUT = VOH_MAX = VCCO_MAX – 0.9V
(V
CCO_MAX
•
-V
OH_MAX
) = 0.9V
For logic low, VOUT = V
OL_MAX
=V
CCO_MAX
– 1.7V
(VCCO_MAX - VOL_MAX) = 1.7V
Pd_H is power dissipation when the output drives high.
Pd_L is the power dissipation when the output drives low.
Pd_H = [(VOH_MAX – (VCCO_MAX - 2V))/R ] * (VCCO_MAX - VOH_MAX) = [(2V - (VCCO_MAX - VOH_MAX))/R ] * (VCCO_MAX - VOH_MAX) =
L
L
[(2V - 0.9V)/50Ω] * 0.9V = 19.8mW
Pd_L = [(VOL_MAX – (VCCO_MAX - 2V))/R ] * (VCCO_MAX - VOL_MAX) = [(2V - (VCCO_MAX - VOL_MAX))/R ] * (VCCO_MAX - VOL_MAX) =
L
L
[(2V - 1.7V)/50Ω] * 1.7V = 10.2mW
Total Power Dissipation per output pair = Pd_H + Pd_L = 30mW
843246AM
www.icst.com/products/hiperclocks.html
12
REV. A SEPTEMBER 29, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
RELIABILITY INFORMATION
TABLE 8A. θJAVS. AIR FLOW TABLE FOR 24 LEAD SOIC
θJA by Velocity (Linear Feet per Minute)
Multi-Layer PCB, JEDEC Standard Test Boards
0
200
50°C/W
43°C/W
500
38°C/W
NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs.
TABLE 8B. θJAVS. AIR FLOW TABLE FOR 24 LEAD TSSOP
θJA by Velocity (Meters per Second)
Multi-Layer PCB, JEDEC Standard Test Boards
0
1
2.5
70°C/W
65°C/W
62°C/W
TRANSISTOR COUNT
The transistor count for ICS843246 is: 3863
843246AM
www.icst.com/products/hiperclocks.html
13
REV. A SEPTEMBER 29, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
PACKAGE OUTLINE - M SUFFIX
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
FOR
24 LEAD SOIC
PACKAGE OUTLINE - G SUFFIX
FOR
Millimeters
SYMBOL
Minimum
N
24 LEAD TSSOP
TABLE 9B. PACKAGE DIMENSIONS
TABLE 9A. PACKAGE DIMENSIONS
SYMBOL
Maximum
Millimeters
Minimum
N
24
Maximum
24
A
--
2.65
A
--
1.20
A1
0.10
--
A1
0.05
0.15
A2
2.05
2.55
A2
0.80
1.05
B
0.33
0.51
b
0.19
0.30
C
0.18
0.32
c
0.09
0.20
D
15.20
15.85
D
7.70
7.90
E
7.40
7.60
E
e
H
1.27 BASIC
E1
10.00
10.65
6.40 BASIC
4.30
e
4.50
0.65 BASIC
h
0.25
0.75
L
0.45
0.75
L
0.40
1.27
α
0°
8°
α
0°
8°
aaa
--
0.10
Reference Document: JEDEC Publication 95, MS-013, MO-119
843246AM
ICS843246
Reference Document: JEDEC Publication 95, MO-153
www.icst.com/products/hiperclocks.html
14
REV. A SEPTEMBER 29, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS843246
FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
TABLE 10. ORDERING INFORMATION
Part/Order Number
Marking
Package
Shipping Packaging
Temperature
ICS843246AM
TBD
24 Lead SOIC
tube
0°C to 70°C
ICS843246AMT
TBD
24 Lead SOIC
1000 tape & reel
0°C to 70°C
ICS843246AMLF
TBD
24 Lead "Lead-Free" SOIC
tube
0°C to 70°C
ICS843246AMLFT
TBD
24 Lead "Lead-Free" SOIC
1000 tape & reel
0°C to 70°C
ICS843246AG
ICS843246AG
24 Lead TSSOP
tube
0°C to 70°C
ICS843246AGT
ICS843246AG
24 Lead TSSOP
2500 tape & reel
0°C to 70°C
ICS843246AGLF
TBD
24 Lead "Lead-Free" TSSOP
tube
0°C to 70°C
ICS843246AGLFT
TBD
24 Lead "Lead-Free" TSSOP
2500 tape & reel
0°C to 70°C
NOTE: Par ts that are ordered with an "LF" suffix to the par t number are the Pb-Free configuration and are RoHS compliant.
The aforementioned trademarks, HiPerClockS and FEMTOCLOCKS are trademarks of Integrated Circuit Systems, Inc. or its subsidiaries in the United States and/or other countries.
While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems, Incorporated (ICS) assumes no responsibility for either its use
or for 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.
843246AM
www.icst.com/products/hiperclocks.html
15
REV. A SEPTEMBER 29, 2005
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