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Электронный компонент: ICS8431AMI-21

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8431AMI-21
www.icst.com/products/hiperclocks.html
REV. A AUGUST 2, 2005
1
Integrated
Circuit
Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
G
ENERAL
D
ESCRIPTION
The ICS8431I-21 is a general purpose clock fre-
quency synthesizer for IA64/32 application and a
member of the HiPerClockSTM family of High Per-
formance Clock Solutions from ICS. The VCO op-
erates at a frequency range of 250MHz to 700MHz
providing an output frequency range of 62.5MHz to 350MHz.
The output frequency can be programmed using the parallel in-
terface, M0 through M8 to the configuration logic, and the output
divider control pin, DIV_SEL. Spread spectrum clocking is pro-
grammed via the control inputs SSC_CTL0 and SSC_CTL1.
Programmable features of the ICS8431I-21 support four op-
erational modes. The four modes are spread spectrum clock-
ing (SSC), non-spread spectrum clock and two test modes
which are controlled by the SSC_CTL[1:0] pins. Unlike other
synthesizers, the ICS8431I-21 can immediately change
spread-spectrum operation without having to reset the device.
In SSC mode, the output clock is modulated in order to achieve
a reduction in EMI. In one of the PLL bypass test modes, the
PLL is disconnected as the source to the differential output
allowing an external source to be connected to the TEST_I/O
pin. This is useful for in-circuit testing and allows the differen-
tial output to be driven at a lower frequency throughout the
system clock tree. In the other PLL bypass mode, the oscilla-
tor divider is used as the source to both the M and the Fout
divide by 2. This is useful for characterizing the oscillator and
internal dividers.
XTAL_IN
XTAL_OUT
M0:M8
PLL
FOUT
nFOUT
16
TEST_I/O
OSC
VCO
2
4
PHASE
DETECTOR
M
SSC
Control
Logic
Configuration
Logic
nP_LOAD
SSC_CTL0
F
EATURES
Fully integrated PLL
Differential 3.3V LVPECL output
Crystal oscillator interface
Output frequency range: 62.5MHz to 350MHz
Crystal input frequency range: 14MHz to 25MHz
VCO range: 250MHz to 700MHz
Programmable PLL loop divider for generating a variety
of output frequencies
Spread Spectrum Clocking (SSC) fixed at 1/2% modulation
for environments requiring ultra low EMI
PLL bypass modes supporting in-circuit testing and on-chip
functional block characterization
Cycle-to-cycle jitter: 30ps (maximum)
3.3V supply voltage
-40C to 85C ambient operating temperature
Replaces ICS8431I-01
Available in both, Standard and RoHS/Lead-Free
compliant packages
B
LOCK
D
IAGRAM
P
IN
A
SSIGNMENT
SSC_CTL1
M0
M1
M2
M3
M4
M5
M6
M7
M8
SSC_CTL0
SSC_CTL1
V
EE
TEST_I/O
V
CC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
nP_LOAD
V
CC
XTAL_IN
XTAL_OUT
nc
nc
V
CCA
V
EE
MR
DIV_SEL
V
CCO
FOUT
nFOUT
V
EE
ICS8431I-21
28-Lead SOIC
7.5mm x 18.05mm x 2.25mm package body
M Package
Top View
DIV_SEL
HiPerClockSTM
ICS
8431AMI-21
www.icst.com/products/hiperclocks.html
REV. A AUGUST 2, 2005
2
Integrated
Circuit
Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
The PLL loop divider or M divider is programmed by using
inputs M0 through M8. While the nP_LOAD input is held LOW,
the data present at M0:M8 is transparent to the M divider. On
the LOW-to-HIGH transition of nP_LOAD, the M0:M8 data is
latched into the M divider and any further changes at the
M0:M8 inputs will not be seen by the M divider until the next
LOW transition on nP_LOAD.
The relationship between the VCO frequency, the crystal fre-
quency and the M divider is defined as follows:
The M value and the required values of M0:M8 for programming
the VCO are shown in
Table 3B, Programmable VCO Frequency
Function Table. The frequency out is defined as follows:
For the ICS8431I-21, the output divider may be set to either
2 or 4 by the DIV_SEL pin. For an input of 16 MHz, valid
M values for which the PLL will achieve lock are defined as:
250
M 511.
F
UNCTIONAL
D
ESCRIPTION
The ICS8431I-21 features a fully integrated PLL and therefore
requires no external components for setting the loop bandwidth.
The output of the oscillator is divided by 16 prior to the phase
detector. With a 16MHz crystal this provides a 1MHz reference
frequency. The VCO of the PLL operates over a range of 250MHz
to 700MHz. The output of the M divider is also applied to the phase
detector.
The phase detector and the M divider force the VCO output
frequency to be M times the reference frequency by adjusting
the VCO control voltage. Note that for some values of M (ei-
ther too high or too low), the PLL will not achieve lock. The
output of the VCO is scaled by a divider prior to being sent to
the LVPECL output buffer. The divider provides a 50% output
duty cycle.
The programmable features of the ICS8431I-21 support four
output operational modes and a programmable M divider and
output divider. The four output operational modes are spread
spectrum clocking (SSC), non-spread spectrum clock and
two test modes and are controlled by the SSC_CTL[1:0] pins.
16
M
fVCO =
fxtal x
N
FOUT =
fVCO
=
16 x N
fxtal x M
8431AMI-21
www.icst.com/products/hiperclocks.html
REV. A AUGUST 2, 2005
3
Integrated
Circuit
Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
T
ABLE
1. P
IN
D
ESCRIPTIONS
T
ABLE
2. P
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8431AMI-21
www.icst.com/products/hiperclocks.html
REV. A AUGUST 2, 2005
4
Integrated
Circuit
Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
T
ABLE
3A. SSC C
ONTROL
I
NPUT
F
UNCTION
T
ABLE
T
ABLE
3B. P
ROGRAMMABLE
VCO F
REQUENCY
F
UNCTION
T
ABLE
(NOTE 1)
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T
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1
8431AMI-21
www.icst.com/products/hiperclocks.html
REV. A AUGUST 2, 2005
5
Integrated
Circuit
Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
T
ABLE
4B. LVCMOS / LVTTL DC C
HARACTERISTICS
,
V
CC
= V
CCA
= V
CCO
= 3.3V5%, T
A
= -40C
TO
85C
T
ABLE
4C. LVPECL DC C
HARACTERISTICS
,
V
CC
= V
CCA
= V
CCO
= 3.3V5%, T
A
= -40C
TO
85C
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UPPLY
DC C
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A
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TO
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1
A
m
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
CC
4.6V
Inputs, V
I
-0.5V to V
CC
+ 0.5V
Outputs, I
O
Continuous Current
50mA
Surge Current
100mA
Package Thermal Impedance,
JA
46.2C/W (0 lfpm)
Storage Temperature, T
STG
-65C to 150C
8431AMI-21
www.icst.com/products/hiperclocks.html
REV. A AUGUST 2, 2005
6
Integrated
Circuit
Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
T
ABLE
6. AC C
HARACTERISTICS
,
V
CC
= V
CCA
= V
CCO
= 3.3V5%, T
A
= -40C
TO
85C
T
ABLE
5. C
RYSTAL
C
HARACTERISTICS
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8431AMI-21
www.icst.com/products/hiperclocks.html
REV. A AUGUST 2, 2005
7
Integrated
Circuit
Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
P
ARAMETER
M
EASUREMENT
I
NFORMATION
O
UTPUT
R
ISE
/F
ALL
T
IME
3.3V O
UTPUT
L
OAD
AC T
EST
C
IRCUIT
SCOPE
Qx
nQx
LVPECL
2V
O
UTPUT
D
UTY
C
YCLE
/P
ULSE
W
IDTH
/P
ERIOD
t
jit(cc) =
t
cycle n
t
cycle n+1
1000 Cycles
t
cycle n
t
cycle n+1
-1.3V 0.165V
nFOUT
FOUT
Clock
Outputs
20%
80%
80%
20%
t
R
t
F
V
SW I N G
t
PW
t
PERIOD
t
PW
t
PERIOD
odc =
x 100%
FOUT
nFOUT
C
YCLE
-
TO
-C
YCLE
J
ITTER
V
CC
,
V
CCA
, V
CCO
V
EE
8431AMI-21
www.icst.com/products/hiperclocks.html
REV. A AUGUST 2, 2005
8
Integrated
Circuit
Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
As in any high speed analog circuitry, the power supply pins
are vulnerable to random noise. The ICS8431I-21 provides
separate power supplies to isolate any high switching noise
from the outputs to the internal PLL. V
CC
, V
CCA
, and V
CCO
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, better power supply iso-
lation is required.
Figure 3 illustrates how a 10
along with a
10
F and a .01F bypass capacitor should be connected to
each V
CCA
pin.
F
IGURE
3. P
OWER
S
UPPLY
F
ILTERING
10
V
CCA
10
F
.01
F
3.3V
.01
F
V
CC
P
OWER
S
UPPLY
F
ILTERING
T
ECHNIQUES
A
PPLICATION
I
NFORMATION
The clock layout topology shown below is typical for
IA64/32 platforms. The two different layouts mentioned are
recommended only as guidelines.
FOUT and nFOUT are low impedance follower outputs that
generate ECL/LVPECL compatible outputs. Therefore, terminat-
ing resistors (DC current path to ground) or current sources
must be used for functionality. These outputs are designed to
F
IGURE
2B. LVPECL O
UTPUT
T
ERMINATION
F
IGURE
2A. LVPECL O
UTPUT
T
ERMINATION
V
CC
- 2V
50
50
RTT
Z
o
= 50
Z
o
= 50
FOUT
FIN
RTT =
Z
o
1
((V
OH
+ V
OL
) / (V
CC
2)) 2
drive 50
transmission lines. Matched impedance techniques
should be used to maximize operating frequency and minimize
signal distortion.
Figures 2A and 2B 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.
T
ERMINATION
FOR
LVPECL O
UTPUTS
3.3V
125
125
84
84
Z
o
= 50
Z
o
= 50
FOUT
FIN
8431AMI-21
www.icst.com/products/hiperclocks.html
REV. A AUGUST 2, 2005
9
Integrated
Circuit
Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
S
PREAD
S
PECTRUM
Spread-spectrum clocking is a frequency modulation tech-
nique for EMI reduction. When spread-spectrum is enabled,
a 30kHz triangle waveform is used with 0.5% down-spread
(+0.0% / -0.5%) from the nominal 200MHz clock frequency.
An example of a triangle frequency modulation profile is shown
in
Figure 4A below. The ramp profile can be expressed as:
Fnom = Nominal Clock Frequency in Spread OFF mode
(200MHz with 16MHz IN)
Fm = Nominal Modulation Frequency (30kHz)
= Modulation Factor (0.5% down spread)
(1 -
) fnom + 2 fm x x fnom x t when 0 < t <
,
(1 -
) fnom - 2 fm x x fnom x t when
< t <
1
2 fm
1
2 fm
1
fm
The ICS8431I-21 triangle modulation frequency deviation will
not exceed 0.6% down-spread from the nominal clock fre-
quency (+0.0% / -0.5%). An example of the amount of down
spread relative to the nominal clock frequency can be seen in
the frequency domain, as shown in
Figure 4B. The ratio of
this width to the fundamental frequency is typically 0.4%, and
will not exceed 0.6%. The resulting spectral reduction will be
greater than 7dB, as shown in
Figure 4B. It is important to
note the ICS8431I-21 7dB minimum spectral reduction is the
component-specific EMI reduction, and will not necessarily
be the same as the system EMI reduction.
F
IGURE
4B. 200MH
Z
C
LOCK
O
UTPUT
IN
F
REQUENCY
D
OMAIN
(A) S
PREAD
-S
PECTRUM
OFF (B) S
PREAD
-S
PECTRUM
ON
F
IGURE
4A. T
RIANGLE
F
REQUENCY
M
ODULATION
- 10 dBm
= .4%
B
A
Fnom
(1 -
) Fnom
0.5/fm
1/fm
C
RYSTAL
I
NPUT
I
NTERFACE
The ICS8431I-21 has been characterized with 18pF parallel resonant
crystals. The capacitor values, C1 and C2, shown in
Figure 3 below
were determined using a 25MHz, 18pF parallel resonant crystal and
Figure 3. C
RYSTAL
I
NPUT
I
NTERFACE
were chosen to minimize the ppm error. The optimum C1 and C2
values can be slightly adjusted for different board layouts.
C1
22p
X1
18pF Parallel Crystal
C2
22p
XTAL_OUT
XTAL_IN
8431AMI-21
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ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
The schematic of the ICS8431I-21 layout example used in
this layout guideline is shown in
Figure 5A. The ICS8431I-21
recommended PCB board layout for this example is shown
L
AYOUT
G
UIDELINE
in
Figure 5B. This layout example is used as a general guide-
line. The layout in the actual system will depend on the se-
lected component types and the density of the P.C. board.
F
IGURE
5A. S
CHEMATIC
E
XAMPLE
C4
10uF
U1
ICS8431-21
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
28
27
26
25
M0
M1
M2
M3
M4
M5
M6
M7
M8
SSC_CTL0
SSC_CTL1
VEE
TEST_IO
VCC
VEE
nFOUT
FOUT
VCCO
DIV_SEL
MR
VEE
VCCA
NC
NC
nP_LOAD
VCC
XTAL_IN
XTAL_OUT
R5
10
C6
0.01uF
C3
0.01uF
R3
125
C7
22pF
VCC
VCC
Zo = 50 Ohm
C2
0.1uF
RD2
1K
R4
84
To Logic
Input
pins
To Logic
Input
pins
RU1
1K
RD1
SP
Logic Input Pin Examples
VCC=3.3V
VCC
Zo = 50 Ohm
C8
22pF
Set Logic
Input to
'0'
RU2
SP
R1
125
X1
VCC
VCCA
Set Logic
Input to
'1'
C1
0.1uF
+
-
VCC
SP=Spare, not installed
VCC
R2
84
VCC
ICS8431I-21
8431AMI-21
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ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
F
IGURE
5B. PCB B
OARD
L
AYOUT
F
OR
ICS8431I-21
The following component footprints are used in this layout
example:
All the resistors and capacitors are size 0603.
P
OWER
AND
G
ROUNDING
Place the decoupling capacitors C1, C2 and C6, as close as
possible to the power pins. If space allows, placment of the
decoupling capacitor on the component side is preferred. This
can reduce unwanted inductance between the decoupling ca-
pacitor and the power pin generated by the via.
Maximize the power and ground pad sizes and number of vias
capacitors. This can reduce the inductance between the power
and ground planes and the component power and ground pins.
The RC filter consisting of R5, C3, and C4 should be placed as
close to the V
CCA
pin as possible.
C
LOCK
T
RACES
AND
T
ERMINATION
Poor signal integrity can degrade the system performance or
cause system failure. In synchronous high-speed digital systems,
the clock signal is less tolerant to poor signal integrity than other
signals. Any ringing on the rising or falling edge or excessive ring
back can cause system failure. The shape of the trace and the
trace delay might be restricted by the available space on the board
and the component location. While routing the traces, the clock
signal traces should be routed first and should be locked prior to
routing other signal traces.
The 50
output trace pair should have same length.
Avoid sharp angles on the clock trace. Sharp angle turns
cause the characteristic impedance to change on the
transmission lines.
Keep the clock traces on the same layer. Whenever pos-
sible, avoid placing vias on the clock traces. Placement
of vias on the traces can affect the trace characteristic
impedance and hence degrade signal integrity.
To prevent cross talk, avoid routing other signal traces in
parallel with the clock traces. If running parallel traces is
unavoidable, allow a separation of at least three trace
widths between the differential clock trace and the other
signal trace.
Make sure no other signal traces are routed between the
clock trace pair.
The matching termination resistors should be located as
close to the receiver input pins as possible.
The matching termination resistors R1, R2, R3 and R4 should
be located as close to the receiver input pins as possible.
Other termination scheme can also be used but is not shown
in the example.
C
RYSTAL
The crystal X1 should be located as close as possible to the pins
25 (XTAL_OUT) and 26 (XTAL_IN). The trace length between the
X1 and U1 should be kept to a minimum to avoid unwanted para-
sitic inductance and capacitance. Other signal traces should not
be routed near the crystal traces.
C4
Signals
X1
C3
VCC
GND
VIA
C1
Zo=50 Ohm
U1
Zo=50 Ohm
C2
C8
R5
C6
ICS8431-21
C7
8431AMI-21
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REV. A AUGUST 2, 2005
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Integrated
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Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
P
OWER
C
ONSIDERATIONS
This section provides information on power dissipation and junction temperature for the ICS8431I-21.
Equations and example calculations are also provided.
1. Power Dissipation.
The total power dissipation for the ICS8431I-21 is the sum of the core power plus the power dissipated in the load(s).
The following is the power dissipation for V
CC
= 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
= V
CC_MAX
* I
EE_MAX
= 3.465V * 155mA = 537.1mW
Power (outputs)
MAX
= 30mW/Loaded Output pair
If all outputs are loaded, the total power is 1 * 30mW = 30mW
Total Power
_MAX
(3.465V, with all outputs switching) = 537.1mW + 30mW = 567.1mW
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 HiPerClockS
TM
devices is 125C.
The equation for Tj is as follows: Tj =
JA
* Pd_total + T
A
Tj = Junction Temperature
JA
= Junction-to-Ambient Thermal Resistance
Pd_total = Total Device Power Dissipation (example calculation is in section 1 above)
T
A
= Ambient Temperature
In order to calculate junction temperature, the appropriate junction-to-ambient thermal resistance
JA
must be used. Assuming a
moderate air flow of 200 linear feet per minute and a multi-layer board, the appropriate value is 39.7C/W per Table 7 below.
Therefore, Tj for an ambient temperature of 85C with all outputs switching is:
85C + 0.567W * 39.7C/W = 107.5C. This is below the limit of 125C.
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).


JA
by Velocity (Linear Feet per Minute)
0
200
500
Single-Layer PCB, JEDEC Standard Test Boards
76.2C/W
60.8C/W
53.2C/W
Multi-Layer PCB, JEDEC Standard Test Boards
46.2C/W
39.7C/W
36.8C/W
NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs.
Table 7. T
HERMAL
R
ESISTANCE


JA
FOR
28-
PIN
SOIC, F
ORCED
C
ONVECTION
8431AMI-21
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ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
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 6.
T
o calculate worst case power dissipation into the load, use the following equations which assume a 50
load, and a termination
voltage of V
CCO
- 2V.
For logic high, V
OUT
= V
OH_MAX
= V
CCO_MAX
0.9V
(V
CCO_MAX
- V
OH_MAX
) = 0.9V
For logic low, V
OUT
= V
OL_MAX
= V
CCO_MAX
1.7V
(V
CCO_MAX
- V
OL_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 = [(V
OH_MAX
(V
CCO_MAX
- 2V))/R
L
] * (V
CCO_MAX
- V
OH_MAX
) = [(2V - (V
CCO_MAX
- V
OH_MAX
))/R
L
] * (V
CCO_MAX
- V
OH_MAX
) =
[(2V - 0.9V)/50
] * 0.9V = 19.8mW
Pd_L = [(V
OL_MAX
(V
CCO_MAX
- 2V))/R
L
] * (V
CCO_MAX
- V
OL_MAX
) = [(2V - (V
CCO_MAX
- V
OL_MAX
))/R
L
] * (V
CCO_MAX
- V
OL_MAX
) =
[(2V - 1.7V)/50
] * 1.7V = 10.2mW
Total Power Dissipation per output pair = Pd_H + Pd_L = 30mW
F
IGURE
6. LVPECL D
RIVER
C
IRCUIT
AND
T
ERMINATION
Q1
V
OUT
V
CCO
R L
50
V
CCO
- 2V
8431AMI-21
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REV. A AUGUST 2, 2005
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Integrated
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ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
R
ELIABILITY
I
NFORMATION
T
RANSISTOR
C
OUNT
The transistor count for ICS8431I-21 is: 4790
T
ABLE
8.
JA
VS
. A
IR
F
LOW
T
ABLE
FOR
28 L
EAD
SOIC


JA
by Velocity (Linear Feet per Minute)
0
200
500
Single-Layer PCB, JEDEC Standard Test Boards
76.2C/W
60.8C/W
53.2C/W
Multi-Layer PCB, JEDEC Standard Test Boards
46.2C/W
39.7C/W
36.8C/W
NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs.
8431AMI-21
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REV. A AUGUST 2, 2005
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Integrated
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ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
P
ACKAGE
O
UTLINE
- M S
UFFIX
FOR
28 L
EAD
SOIC
T
ABLE
9. P
ACKAGE
D
IMENSIONS
Reference Document: JEDEC Publication 95, MS-013, MO-119
L
O
B
M
Y
S
s
r
e
t
e
m
i
l
l
i
M
M
U
M
I
N
I
M
M
U
M
I
X
A
M
N
8
2
A
-
-
5
6
.
2
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0
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8431AMI-21
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REV. A AUGUST 2, 2005
16
Integrated
Circuit
Systems, Inc.
ICS8431I-21
350MH
Z
, L
OW
J
ITTER
, C
RYSTAL
O
SCILLATOR
-
TO
-3.3V LVPECL F
REQUENCY
S
YNTHESIZER
T
ABLE
10. O
RDERING
I
NFORMATION
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 and industrial applications. Any other applications such as those requiring 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.
The aforementioned trademark, HiPerClockSTM is a trademark of Integrated Circuit Systems, Inc. or its subsidiaries in the United States and/or other countries.
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