IDT 841664AGILF

PRELIMINARY
ICS841664I
FEMTOCLOCK™ CRYSTAL-TO-HCSL
CLOCK GENERATOR
GENERAL DESCRIPTION
FEATURES
The ICS841664I is an optimized sRIO clock
ICS
generator and member of the HiPerClocks™ family
HiPerClockS™ of high-performance clock solutions from IDT.
The device uses a 25MHz parallel crystal to generate 125MHz and 156.25MHz clock signals,
replacing solutions requiring multiple oscillator and fanout buffer
solutions. The device has excellent phase jitter (< 1ps rms) suitable to clock components requiring precise and low-jitter sRIO
clock signals. Designed for telecom, networking and industrial
applications, the ICS841664I can also drive the high-speed
sRIO SerDes clock inputs of communication processors, DSPs,
switches and bridges.
• Four differential HCSL clock outputs: configurable for sRIO
(125MHz or 156.25MHz) clock signals
One REF_OUT LVCMOS/LVTTL clock output
• Selectable crystal oscillator interface, 25MHz, 18pF parallel
resonant crystal or LVCMOS/LVTTL single-ended reference
clock input
• Supports the following output frequencies:
125MHz or 156.25MHz
• VCO: 625MHz
• PLL bypass and output enable
• RMS phase jitter, using a 25MHz crystal (1.875MHz - 20MHz):
0.35ps (typical) @ 125MHz
• Full 3.3V power supply mode
• -40°C to 85°C ambient operating temperature
• Available in both standard (RoHS 5) and lead-free (RoHS 6)
packages
BLOCK DIAGRAM
PIN ASSIGNMENT
XTAL_IN
OSC
FemtoClock
PLL
XTAL_OUT
REF_IN Pulldown
1
QA0
1
0
nQA0
0
÷NA
QA1
VCO = 625MHz
nQA1
REF_SEL Pulldown
M = ÷25
QB0
IREF
nQB0
÷NB
BYPASS Pulldown
QB1
FSEL[0:1] Pulldown
nQB1
MR/nOE Pulldown
REF_OUT
nREF_OE Pullup
VDD
REF_OUT
GND
QA0
nQA0
VDDOA
GND
QA1
nQA1
nREF_OE
BYPASS
REF_IN
REF_SEL
VDDA
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
IREF
FSEL0
FSEL1
QB0
nQB0
VDDOB
GND
QB1
nQB1
MR/nOE
VDD
XTAL_IN
XTAL_OUT
GND
ICS841664I
28-Lead TSSOP
6.1mm x 9.7mm x 0.925mm
package body
G Package
Top View
The Preliminary Information presented herein represents a product in pre-production. The noted characteristics are based on initial product characterization
and/or qualification. Integrated Device Technology, Incorporated (IDT) reserves the right to change any circuitry or specifications without notice.
IDT ™ / ICS™ HCSL CLOCK GENERATOR
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ICS841664I
FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
TABLE 1. PIN DESCRIPTIONS
Number
Name
1, 18
VDD
Power
Core supply pins.
2
REF_OUT
Output
LVCMOS/LVTTL reference frequency clock output.
3, 7, 15, 22
4, 5 ,
8, 9
6
GND
QA0, nQA0,
QA1, nQA1
VDDOA
Power
Power supply ground.
Ouput
Differential Bank A output pairs. HCSL interface levels.
Power
10
nREF_OE
Input
Pullup
11
BYPASS
Input
Pulldown
12
REF_IN
Input
Pulldown
13
REF_SEL
Input
Pulldown
14
VDDA
XTAL_OUT,
XTAL_IN
Power
19
MR/nOE
Input
Output supply pin for Bank A outputs.
Active low REF_OUT enable/disable. See Table 3E.
LVCMOS/LVTTL interface levels.
Selects PLL operation/PLL bypass operation.
See Table 3C. LVCMOS/LVTTL interface levels.
LVCMOS/LVTTL PLL reference clock input.
Reference select. Selects the input reference source.
See Table 3B. LVCMOS/LVTTL interface levels.
Analog supply pin.
Parallel resonant cr ystal interface. XTAL_OUT is the output,
XTAL_IN is the input. (PLL reference.)
Active HIGH master reset. Active LOW output enable. When logic HIGH,
the internal dividers are reset and the outputs are in high impedance
(HiZ). When logic LOW, the internal dividers and the outputs are enabled.
See Table 3D. LVCMOS/LVTTL interface levels.
20, 21
24, 25
23
nQB1, QB1
nQB0, QB0
VDDOB
FSEL1,
FSEL0
16, 17
26, 27
Type
Description
Input
Pulldown
Output
Differential Bank B output pairs. HCSL interface levels.
Power
Output supply pin for Bank B outputs.
Input
Pulldown Output frequency select pins. LVCMOS/LVTTL interface levels.
HCSL current reference resistor output. A fixed precision resistor (475Ω)
from this pin to ground provides a reference current used for differential
current-mode QXx/nQXx clock outputs.
NOTE: Pullup and Pulldown refer to internal input resistors. See Table 2, Pin Characteristics, for typical values.
28
IREF
Output
TABLE 2. PIN CHARACTERISTICS
Symbol
Parameter
CIN
Input Capacitance
RPULLUP
Power Dissipation
Capacitance
Input PullupResistor
RPULLDOWN
Input Pulldown Resistor
CPD
IDT ™ / ICS™ HCSL CLOCK GENERATOR
Test Conditions
VDD, VDDOA, VDDOB = 3.465V
2
Minimum
Typical
Maximum
Units
4
pF
18
pF
51
kΩ
51
kΩ
ICS841664AGI REV. A JANUARY 30, 2009
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
TABLE 3A. FSELX FUNCTION TABLE (fref = 25MHZ)
Inputs
FSEL1
FSEL0
Outputs Frequency Settings
M
QA0:1/nQA0:1
QB0:1/nQB0:1
0
0
25
VCO/5 (125MHz)
VCO/5 (125MHz)
0
1
25
VCO/5 (125MHz)
VCO/4 (156.25MHz)
1
0
25
VCO/5 (125MHz)
QB0:1 = L, nQB0:1 = H
1
1
25
VCO/4 (156.25MHz)
VCO/4 (156.25MHz)
TABLE 3B. REF_SEL FUNCTION TABLE
TABLE 3C. BYPASS FUNCTION TABLE
Input
REF_SEL
Input
Input Reference
BYPASS
0
XTAL
0
PLL on
1
REF_IN
1
PLL bypassed (QA, QB = fref/N)
PLL Configuration
NOTE 1: Asynchr. function (may cause output glitch).
TABLE 3D. MR/nOE FUNCTION TABLE
Input
MR/nOE
FunctionNOTE 1
0
Outputs enabled
1
Device reset, outputs disabled (Low)
NOTE 1: Asynchr. function (may cause output glitch).
TABLE 3E. nREF_OE FUNCTION TABLE
Input
nREF_OE
FunctionNOTE 1
0
REF_OUT enabled
1
REF_OUT disabled (high impedance)
NOTE 1: Asynchr. function (may cause output glitch).
IDT ™ / ICS™ HCSL CLOCK GENERATOR
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VDD
4.6V
Inputs, VI
-0.5V to VDD + 0.5V
Outputs, VO
-0.5V to VDDO_X + 0.5V
Package Thermal Impedance, θJA
64.5°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, VDD = VDDOA = VDDOB = 3.3V±5%, TA = -40°C TO 85°C
Symbol
Parameter
Test Conditions
Minimum
Typical
Maximum
Units
VDD
Core Supply Voltage
3.135
3.3
3.465
V
VDDA
Analog Supply Voltage
VDD – 0.15
3.3
3.465
V
VDDOA,
VDDOB
Output Supply Voltage
3.135
3.3
3.465
V
IDD
Power Supply Current
70
mA
IDDA
Analog Supply Current
15
mA
IDDOA,
IDDOB
Output Supply Current
75
mA
TABLE 4B. LVCMOS / LVTTL DC CHARACTERISTICS, VDD = 3.3V±5%, TA = -40°C TO 85°C
Symbol
VIH
Parameter
Input High Voltage
VIL
Input Low Voltage
IIH
IIL
Input High Current
Input Low Current
Test Conditions
Minimum Typical
2
Maximum
VDD + 0.3
Units
V
0. 8
V
VDD = VIN = 3.465 V
15 0
µA
VDD = VIN = 3.465V
5
µA
-0.3
REF_IN, REF_SEL,
BYPASS, MR/nOE,
FSEL0, FSEL1
nREF_OE
REF_IN, REF_SEL,
BYPASS, MR/nOE,
FSEL0, FSEL1
nREF_OE
VDD = 3.465V, VIN = 0V
-5
µA
VDD = 3.465V, VIN = 0V
-150
µA
Ouput High Voltage;
2.275
REF_OUT
VDD = 3.465V
NOTE 1
Ouput Low Voltage;
REF_OUT
VDD = 3.465V
VOL
NOTE 1
Output Impedance
REF_OUT
VDD = 3.465V
20
ZOUT
NOTE 1: Outputs terminated with 50Ω to VDD/2. See Parameter Measurement Information Section,
Output Load Test Circuit diagram.
VOH
IDT ™ / ICS™ HCSL CLOCK GENERATOR
4
V
0.775
V
Ω
ICS841664AGI REV. A JANUARY 30, 2009
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
TABLE 5. CRYSTAL CHARACTERISTICS
Parameter
Test Conditions
Minimum
Mode of Oscillation
Typical
Maximum
Units
Fundamental
Frequency
25
MHz
Equivalent Series Resistance (ESR)
50
Ω
Shunt Capacitance
7
pF
0.1
mW
Maximum
Units
Drive Level
NOTE: Characterized using an 18pF parallel resonant crystal.
TABLE 6A. LVCMOS AC CHARACTERISTICS, VDD = 3.3V±5%, TA = -40°C TO 85°C
Symbol Parameter
Test Conditions
fMAX
Output Frequency
tR / tF
Output Rise/Fall Time
o dc
Output Duty Cycle
Minimum
REF_OUT
20% to 80%
Typical
25
MHz
1
ns
50
%
TABLE 6B. HCSL AC CHARACTERISTICS, VDD = VDDOA = VDDOB = 3.3V±5%, TA = -40°C TO 85°C
Symbol Parameter
Test Conditions
fMAX
Output Frequency
tjit(Ø)
RMS Phase Jitter (Random);
NOTE 1
Minimum
Maximum
Units
125
MHz
VCO/4
125MHz,
(1.875MHz - 20MHz)
156.25MHz,
(1.875MHz - 20MHz)
156.25
MHz
0.35
ps
0.35
ps
tL
Output Skew;
NOTE 2, 3
PLL Lock Time
VHIGH
Voltage High
660
VLOW
Voltage Low
-150
tsk(o)
Typical
VCO/5
QAx/nQAx,
QBx/nQBx
ps
700
1
ms
850
mV
150
mV
VOVS
Max. Voltage, Overshoot
0.3
0.3
V
VUDS
Min. Voltage, Undershoot
-0.3
-0.3
V
Vrb
Ringback Voltage
0.2
V
Absolute Crossing Voltage
250
550
mV
Total Variation of VCROSS over all
140
mV
ΔVCROSS
edges
QAx/nQAx,
measured between
tR / tF
Output Rise/Fall Time
350
ps
QBx/nQBx
0.175V to 0.525V
Rise/Fall Time Variation
125
ps
ΔtR /ΔtF
QAx/nQAx,
odc
Output Duty Cycle
50
%
QBx/nQBx
NOTE: Electrical parameters are guaranteed over the specified ambient operating temperature range, which is established
when the device is mounted in a test socket with maintained transverse airflow greater than 500 lfpm. The device will meet
specifications after thermal equilibrium has been reached under these conditions.
NOTE: All specifications are taken at 125MHz and 156.25MHz.
NOTE 1: Please refer to the Phase Noise Plot.
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: This parameter is defined in accordance with JEDEC Standard 65.
VCROSS
IDT ™ / ICS™ HCSL CLOCK GENERATOR
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
➤
TYPICAL PHASE NOISE AT 125MHZ AT 3.3V
sRIO Filter
125MHz
NOISE POWER dBc
Hz
RMS Phase Jitter (Random)
1.875MHz to 20MHz = 0.35ps (typical)
Raw Phase Noise Data
➤
➤
Phase Noise Result by adding
an sRIO Filter to raw data
OFFSET FREQUENCY (HZ)
➤
TYPICAL PHASE NOISE AT 156.25MHZ AT 3.3V
sRIO Filter
156.25MHz
Raw Phase Noise Data
➤
➤
NOISE POWER dBc
Hz
RMS Phase Jitter (Random)
1.875MHz to 20MHz = 0.35ps (typical)
Phase Noise Result by adding
an sRIO Filter to raw data
OFFSET FREQUENCY (HZ)
IDT ™ / ICS™ HCSL CLOCK GENERATOR
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
PARAMETER MEASUREMENT INFORMATION
3.3V±5%
3.3V±5%,
1.65V±5%
1.65V±5%
VDD,
VDDOA,
VDDOB
50Ω
33Ω
Measurement
Point
SCOPE
VDD
VDDA
50Ω
VDDA
HSCL
50Ω
33Ω
Qx
LVCMOS
Measurement
Point
GND
GND
50Ω
475Ω
-1.65V±5%
0V
3.3V HCSL OUTPUT LOAD AC TEST CIRCUIT
3.3V LVCMOS OUTPUT LOAD AC TEST CIRCUIT
Phase Noise Plot
Noise Power
nQx
Qx
nQy
Phase Noise Mask
Qy
tsk(o)
f1
Offset Frequency
f2
RMS Jitter = Area Under the Masked Phase Noise Plot
HCSL OUTPUT SKEW
RMS PHASE JITTER
nQA0, nQA1,
nQB0, nQB1
V
DDO
2
REF_OUT
QA0, QA1,
QB0, QB1
t PW
t
odc =
t PW
t
PERIOD
t PW
odc =
x 100%
PERIOD
t PW
x 100%
t PERIOD
t PERIOD
LVCMOS OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD
HCSL OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD
nQA0, nQA1,
nQB0, nQB1
80%
80%
0.525V
0.525V
VSW I N G
REF_OUT
QA0, QA1, 0.175V
QB0, QB1
20%
20%
tR
tF
tR
tF
HCSL OUTPUT RISE/FALL TIME
LVCMOS OUTPUT RISE/FALL TIME
IDT ™ / ICS™ HCSL CLOCK GENERATOR
0.175V
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ICS841664I
FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
APPLICATION INFORMATION
POWER SUPPLY FILTERING TECHNIQUES
As in any high speed analog circuitry, the power supply pins
are vulnerable to random noise. To achieve optimum jitter performance, power supply isolation is required. The ICS841664I
provides separate power supplies to isolate any high switching
noise from the outputs to the internal PLL. VDD, VDDA, VDDOA and
VDDOB should be individually connected to the power supply plane
through vias, and 0.01µF bypass capacitors should be used for
each pin. Figure 1 illustrates this for a generic VDD pin and also
shows that VDDA requires that an additional10Ω resistor along
with a 10µF bypass capacitor be connected to the VDDA pin.
3.3V
VDD
.01μF
10Ω
VDDA
.01μF
10μF
FIGURE 1. POWER SUPPLY FILTERING
CRYSTAL INPUT INTERFACE
The ICS841664I has been characterized with 18pF parallel
resonant crystals. The capacitor values shown in Figure 2 below
were determined using a 25MHz, 18pF parallel resonant crystal
and were chosen to minimize the ppm error.
XTAL_OUT
C1
27p
X1
18pF Parallel Crystal
XTAL_IN
C2
27p
FIGURE 2. CRYSTAL INPUt INTERFACE
IDT ™ / ICS™ HCSL CLOCK GENERATOR
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
LVCMOS TO XTAL INTERFACE
series resistance (Rs) equals the transmission line impedance.
In addition, matched termination at the crystal input will
attenuate the signal in half. This can be done in one of two
ways. First, R1 and R2 in parallel should equal the transmission
line impedance. For most 50Ω applications, R1 and R2 can be
100Ω. This can also be accomplished by removing R1 and
making R2 50Ω.
The XTAL_IN input can accept a single-ended LVCMOS signal
through an AC couple capacitor. A general interface diagram is
shown in Figure 3. The XTAL_OUT pin can be left floating.
The input edge rate can be as slow as 10ns. For LVCMOS
inputs, it is recommended that the amplitude be reduced from
full swing to half swing in order to prevent signal interference
with the power rail and to reduce noise. This configuration
requires that the output impedance of the driver (Ro) plus the
VDD
VCC
VDD
VCC
R1
Ro
.1uf
Rs
Zo = 50
XTAL_IN
R2
Zo = Ro + Rs
XTAL_OUT
FIGURE 3. GENERAL DIAGRAM FOR LVCMOS DRIVER TO XTAL INPUT INTERFACE
RECOMMENDATIONS FOR UNUSED INPUT AND OUTPUT PINS
INPUTS:
OUTPUTS:
CRYSTAL INPUTS
For applications not requiring the use of the crystal oscillator input,
both XTAL_IN and XTAL_OUT can be left floating. Though not
required, but for additional protection, a 1kΩ resistor can be tied
from XTAL_IN to ground.
HCSL OUTPUTS
All unused HCSL 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 OUTPUT
The unused LVCMOS output can be left floating. We recommend
that there is no trace attached.
REF_IN INPUT
For applications not requiring the use of the reference clock,
it can be left floating. Though not required, but for additional
protection, a 1kΩ resistor can be tied from the REF_IN to ground.
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.
IDT ™ / ICS™ HCSL CLOCK GENERATOR
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
RECOMMENDED TERMINATION
Figure 4A is the recommended termination for applications
which require the receiver and driver to be on a separate PCB.
All traces should be 50Ω impedance.
FIGURE 4A. RECOMMENDED TERMINATION
Figure 4B is the recommended termination for applications which
require a point to point connection and contain the driver and
receiver on the same PCB. All traces should all be 50Ω impedance.
FIGURE 4B. RECOMMENDED TERMINATION
IDT ™ / ICS™ HCSL CLOCK GENERATOR
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
SCHEMATIC EXAMPLE
frequency accuracy. One example of HCSL and one example of
LVCMOS terminations are shown in this schematic. The
decoupling capacitors should be located as close as possible to
the power pin.
Figure 5 shows an example of ICS841664I application schematic.
In this example, the device is operated at VCC = 3.3V. The 18pF
parallel resonant 25MHz crystal is used. The C1 = 27pF and C2
= 27pF are recommended for frequency accuracy. For different
board layout, the C1 and C2 may be slightly adjusted for optimizing
FIGURE 5. ICS841664I SCHEMATIC LAYOUT
IDT ™ / ICS™ HCSL CLOCK GENERATOR
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
POWER CONSIDERATIONS
This section provides information on power dissipation and junction temperature for the ICS841664I.
Equations and example calculations are also provided.
1. Power Dissipation.
The total power dissipation for the ICS841664I is the sum of the core power plus the power dissipated in the load(s).
The following is the power dissipation for VDD = 3.3V + 5% = 3.465V, which gives worst case results.
Core and HCSL Output Power Dissipation
• Power (core)MAX = VDD_MAX * (IDD + IDDA) = 3.465V * (70mA + 15mA) = 294.5mW
• Power (outputs)MAX = 44.5mW/Loaded Output pair
If all outputs are loaded, the total power is 4 * 44.5mW = 178mW
LVCMOS Output Power Dissipation
•
Dynamic Power Dissipation at 25MHz
Power (25MHz) = CPD * Frequency * (VDD)2 = 18pF * 25MHz * (3.465V)2 = 5.40mW per output
Total Power Dissipation
• Total Power
= Power (core) + Power (Outputs) + Total Power (25MHz)
= 294.5mW + 178mW + 5.4mW
= 477.9mW
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 no air
flow and a multi-layer board, the appropriate value is 64.5°C/W per Table 7 below.
Therefore, Tj for an ambient temperature of 85°C with all outputs switching is:
85°C + 0.478W * 64.5°C/W = 115.8°C. This is 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 (multi-layer).
TABLE 7. THERMAL RESISTANCE θJA FOR 28-LEAD TSSOP, FORCED CONVECTION
θJA by Velocity (Meters per Second)
0
Multi-Layer PCB, JEDEC Standard Test Boards
IDT ™ / ICS™ HCSL CLOCK GENERATOR
64.5°C/W
12
1
2.5
60.4°C/W
58.5°C/W
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
3. Calculations and Equations.
The purpose of this section is to calculate power dissipation on the IC per HCSL output pair.
HCSL output driver circuit and termination are shown in Figure 6.
VDD
IOUT = 17mA
➤
VOUT
RREF =
475Ω ± 1%
RL
50Ω
IC
FIGURE 6. HCSL DRIVER CIRCUIT
AND TERMINATION
HCSL is a current steering output which sources a maximum of 17mA of current per output. To calculate worst case on-chip power
dissipation, use the following equations which assume a 50Ω load to ground.
The highest power dissipation occurs when VDD_MAX.
Power = (VDD_MAX – VOUT ) * IOUT
since VOUT = IOUT * RL
Power
= (VDD_MAX – IOUT * RL) * IOUT
= (3.465V – 17mA * 50Ω) * 17mA
Total Power Dissipation per output pair = 44.5mW
IDT ™ / ICS™ HCSL CLOCK GENERATOR
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FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
RELIABILITY INFORMATION
TABLE 8. θJAVS. AIR FLOW TABLE
FOR
28 LEAD TSSOP
θJA by Velocity (Meters per Second)
0
Multi-Layer PCB, JEDEC Standard Test Boards
64.5°C/W
1
2.5
60.4°C/W
58.5°C/W
TRANSISTOR COUNT
The transistor count for ICS841664I is: 2954
PACKAGE OUTLINE
PACKAGE OUTLINE - G SUFFIX FOR 28 LEAD TSSOP
AND
DIMENSIONS
TABLE 9. PACKAGE DIMENSIONS
SYMBOL
Millimeters
Minimum
N
A
Maximum
28
--
1.20
A1
0.05
0.15
A2
0.80
1.05
b
0.19
0.30
c
0.09
0.20
D
9.60
9.80
E
E1
8.10 BASIC
6.00
e
6.20
0.65 BASIC
L
0.45
0.75
α
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Reference Document: JEDEC Publication 95, MO-153
IDT ™ / ICS™ HCSL CLOCK GENERATOR
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ICS841664AGI REV. A JANUARY 30, 2009
ICS841664I
FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
TABLE 10. ORDERING INFORMATION
Part/Order Number
Marking
Package
Shipping Packaging
Temperature
841664AGI
ICS841664AGI
28 Lead TSSOP
tube
-40°C to 85°C
841664AGIT
ICS841664AGI
28 Lead TSSOP
1000 tape & reel
-40°C to 85°C
841664AGILF
ICS841664AGILF
28 Lead "Lead-Free" TSSOP
tube
-40°C to 85°C
841664AGILFT
ICS841664AGILF
28 Lead "Lead-Free" TSSOP
1000 tape & reel
-40°C to 85°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.
While the information presented herein has been checked for both accuracy and reliability, Integrated Device Technology, Incorporated (IDT) 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 IDT. IDT
reserves the right to change any circuitry or specifications without notice. ICS does not authorize or warrant any IDT product for use in life support devices or critical medical instruments.
IDT ™ / ICS™ HCSL CLOCK GENERATOR
15
ICS841664AGI REV. A JANUARY 30, 2009
ICS841664I
FEMTOCLOCK™ CRYSTAL-TO-HCSL CLOCK GENERATOR
PRELIMINARY
Innovate with IDT and accelerate your future networks. Contact:
www.IDT.com
For Sales
For Tech Support
Corporate Headquarters
800-345-7015 (inside USA)
+408-284-8200 (outside USA)
Fax: 408-284-2775
www.IDT.com/go/contactIDT
[email protected]
+480-763-2056
Integrated Device Technology, Inc.
6024 Silver Creek Valley Road
San Jose, CA 95138
United States
800-345-7015 (inside USA)
+408-284-8200 (outside USA)
© 2009 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to change without notice. IDT, the IDT logo, ICS and HiPerClockS are trademarks
of Integrated Device Technology, Inc. Accelerated Thinking is a service mark of Integrated Device Technology, Inc. All other brands, product names and marks are or may be
trademarks or registered trademarks used to identify products or services of their respective owners.
Printed in USA