ICS ICS843004AGI

ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
GENERAL DESCRIPTION
FEATURES
The ICS843004I is a 4 output LVPECL synthesizer
optimized to generate Fibre Channel reference
HiPerClockS™ clock frequencies and is a member of the
HiPerClocksTM family of high performance clock
solutions from ICS. Using a 26.5625MHz 18pF
parallel resonant crystal, the following frequencies can be
generated based on the 2 frequency select pins (F_SEL[1:0]):
212.5MHz, 187.5MHz, 159.375MHz, 156.25MHz, 106.25MHz,
and 53.125MHz. The ICS843004I uses ICS’ 3rd generation low
phase noise VCO technology and can achieve 1ps or lower
typical rms phase jitter, easily meeting Fibre Channel jitter
requirements. The ICS843004I is packaged in a small 24-pin
TSSOP package.
• Four 3.3V LVPECL outputs
ICS
• Selectable crystal oscillator interface
or LVCMOS/LVTTL single-ended input
• Supports the following output frequencies: 212.5MHz,
187.5MHz, 159.375MHz, 156.25MHz, 106.25MHz, 53.125MHz
• VCO range: 560MHz - 680MHz
• Output skew: 50ps (maximum)
• RMS phase jitter @ 212.5MHz, using a 26.5625MHz crystal
(2.55MHz - 20MHz): 0.47ps (typical)
• Full 3.3V or 2.5V supply modes
• -40°C to 85°C ambient operating temperature
• Lead-Free fully RoHS compliant
FREQUENCY SELECT FUNCTION TABLE
Inputs
Input
Frequency
(MHz)
26.5625
F_SEL1 F_SEL0
M Divider
Value
N Divider
Value
M/N Divider
Value
Output
Frequency
(MHz)
0
0
24
3
8
212.5
26.5625
0
1
24
4
6
159.375
26.5625
1
0
24
6
4
106.25
26.5625
1
1
24
12
2
53.125
26.04166
0
1
24
4
6
156.25
23.4375
0
0
24
3
8
187.5
PIN ASSIGNMENT
nQ1
Q1
VCC o
Q0
nQ0
MR
nPLL_SEL
nc
VCCA
F_SEL0
VCC
F_SEL1
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
nQ2
Q2
VCCO
Q3
nQ3
VEE
nc
nXTAL_SEL
TEST_CLK
VEE
XTAL_IN
XTAL_OUT
ICS843004I
24-Lead TSSOP
4.40mm x 7.8mm x 0.92mm
package body
G Package
Top View
Q0
BLOCK DIAGRAM
2
F_SEL[1:0] Pulldown
nPLL_SEL
Pulldown
TEST_CLK Pulldown
F_SEL[1:0]
0 0 ÷3
1
1
26.5625MHz
XTAL_IN
OSC
XTAL_OUT
nXTAL_SEL
0
Phase
Detector
VCO
637.5MHz
01
10
11
÷4
÷6
÷12
0
(w/26.5625MHz
Reference)
nQO
Q1
nQ1
Q2
Pulldown
nQ2
M = 24 (fixed)
MR
843004AGI
Q3
nQ3
Pulldown
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1
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
TABLE 1. PIN DESCRIPTIONS
Number
Name
1, 2
nQ1, Q1
Output
Differential output pair. LVPECL interface levels.
3, 22
VCCO
Power
Output supply pins.
4, 5
Q0, nQ0
Ouput
6
MR
Input
7
nPLL_SEL
Input
8, 18
nc
Unused
9
Power
15, 19
VCCA
F_SEL0,
F_SEL1
VCC
XTAL_OUT,
XTAL_IN
VEE
16
TEST_CLK
Input
17
nXTAL_SEL
Input
20, 21
nQ3, Q3
Output
23, 24
Q2, nQ2
Output
10, 12
11
13, 14
Type
Input
Power
Input
Power
Description
Differential output pair. LVPECL interface levels.
Active HIGH Master Reset. When logic HIGH, the internal dividers are
reset causing the true outputs Qx to go low and the inver ted outputs nQx
Pulldown
to go high. When logic LOW, the internal dividers and the outputs are
enabled. LVCMOS/LVTTL interface levels.
Selects between the PLL and TEST_CLK as input to the dividers. When
Pulldown LOW, selects PLL (PLL Enable). When HIGH, deselects the reference clock
(PLL Bypass). LVCMOS/LVTTL interface levels.
No connect.
Analog supply pin.
Pulldown Frequency select pins. LVCMOS/LVTTL interface levels.
Core supply pin.
Parallel resonant cr ystal interface. XTAL_OUT is the output,
XTAL_IN is the input.
Negative supply pins.
Pulldown LVCMOS/LVTTL clock input.
Selects between cr ystal or TEST_CLK inputs as the the PLL Reference
Pulldown source. Selects XTAL inputs when LOW. Selects TEST_CLK when HIGH.
LVCMOS/LVTTL interface levels.
Differential output pair. LVPECL interface levels.
Differential output pair. LVPECL interface levels.
NOTE: Pulldown refers to internal input resistors. See Table 2, Pin Characteristics, for typical values.
TABLE 2. PIN CHARACTERISTICS
Symbol
Parameter
CIN
Input Capacitance
4
pF
RPULLDOWN
Input Pulldown Resistor
51
kΩ
843004AGI
Test Conditions
Minimum
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2
Typical
Maximum
Units
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
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
70°C/W (0 lfpm)
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 3A. POWER SUPPLY DC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = -40°C TO 85°C
Symbol
Parameter
Minimum
Typical
Maximum
Units
VCC
Core Supply Voltage
Test Conditions
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
I EE
Power Supply Current
130
mA
ICCA
Analog Supply Current
15
mA
Maximum
Units
Included in IEE
TABLE 3B. POWER SUPPLY DC CHARACTERISTICS, VCC = VCCA = VCCO = 2.5V±5%, TA = -40°C TO 85°C
Symbol
Parameter
VCC
Core Supply Voltage
2.375
2.5
2.625
V
VCCA
Analog Supply Voltage
2.375
2.5
2.625
V
2.375
2.5
2.625
V
120
mA
12
mA
VCCO
Output Supply Voltage
I EE
Power Supply Current
ICCA
Analog Supply Current
Test Conditions
Minimum
Typical
Included in IEE
TABLE 3C. LVCMOS / LVTTL DC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5% OR 2.5V±5%, TA = -40°C TO 85°C
Symbol
Parameter
VIH
Input High Voltage
VIL
Input Low Voltage
Test Conditions
VCC = 3.3V ± 5%
Minimum
2.0
VCC = 2.5V ± 5%
1.7
VCC = 3.3V ± 5%
-0.3
0.8
V
VCC = 2.5V ± 5%
-0.3
0. 7
V
IIH
Input High Current
VCC = VIN = 3.465V or 2.625V
IIL
Input Low Current
VCC = 3.465V or 2.625V, VIN = 0V
843004AGI
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3
Typical
Maximum
VCC + 0.3
Units
V
VCC + 0.3
V
150
-5
µA
µA
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
TABLE 3D. LVPECL DC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5% OR 2.5V±5%, TA = -40°C TO 85°C
Symbol
Parameter
Test Conditions
Minimum
Typical
Maximum
Units
VOH
Output High Voltage; NOTE 1
VCCO - 1.4
VCCO - 0.9
V
VOL
Output Low Voltage; NOTE 1
VCCO - 2.0
VCCO - 1.7
V
VSWING
Peak-to-Peak Output Voltage Swing
0.6
1.0
V
Maximum
Units
28.33
MHz
NOTE 1: Outputs terminated with 50Ω to VCCO - 2V.
TABLE 4. CRYSTAL CHARACTERISTICS
Parameter
Test Conditions
Minimum
Mode of Oscillation
Typical
Fundamental
Frequency
23.33
26.5625
Equivalent Series Resistance (ESR)
50
Ω
Shunt Capacitance
7
pF
Maximum
Units
NOTE: Characterized using an 18pF parallel resonant crystal.
TABLE 5A. AC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = -40°C TO 85°C
Symbol
fOUT
tsk(o)
Parameter
Output Frequency
Test Conditions
Minimum
F_SEL[1:0] = 00
186.67
226.66
MHz
F_SEL[1:0] = 01
140
170
MHz
F_SEL[1:0] = 10
93.33
113.33
MHz
F_SEL[1:0] = 11
46.67
56.66
MHz
50
ps
Output Skew; NOTE 1, 3
212.5MHz, (2.55MHz - 20MHz)
tjit(Ø)
tR / tF
Typical
RMS Phase Jitter (Random);
NOTE 2
Output Rise/Fall Time
0.47
159.375MHz, 1.875MHz -20MHz)
0.52
ps
156.25MHz, (1.875MHz - 20MHz)
0.52
ps
106.25MHz, (637KHz - 5MHz)
0.62
ps
53.125MHz, (637KHz - 5MHz)
0.67
ps
20% to 80%
300
F_SEL[1:0] ≠ 00
49
odc
Output Duty Cycle
F_SEL[1:0] = 00
42
NOTE 1: Defined as skew between outputs at the same supply voltages and with equal load conditions.
Measured at VCCO/2.
NOTE 2: Please refer to the Phase Noise Plot.
NOTE 3: This parameter is defined in accordance with JEDEC Standard 65.
843004AGI
ps
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4
600
ps
51
58
%
%
REV. A FEBRUARY 11, 2005
Integrated
Circuit
Systems, Inc.
ICS843004I
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
TABLE 5B. AC CHARACTERISTICS, VCC = VCCA = VCCO = 2.5V±5%, TA = -40°C TO 85°C
Symbol
fOUT
tsk(o)
Parameter
Output Frequency
Test Conditions
Minimum
F_SEL[1:0] = 00
F_SEL[1:0] = 01
Maximum
Units
186.67
226.66
MHz
140
170
MHz
F_SEL[1:0] = 10
93.33
113.33
MHz
F_SEL[1:0] = 11
46.67
56.66
MHz
50
ps
Output Skew; NOTE 1, 3
212.5MHz, (2.55MHz - 20MHz)
tjit(Ø)
tR / tF
Typical
RMS Phase Jitter (Random);
NOTE 2
Output Rise/Fall Time
0.49
159.375MHz, 1.875MHz -20MHz)
0.52
ps
156.25MHz, (1.875MHz - 20MHz)
0.52
ps
106.25MHz, (637KHz - 5MHz)
0.65
ps
53.125MHz, (637KHz - 5MHz)
0.71
ps
20% to 80%
300
F_SEL[1:0] ≠ 00
48
F_SEL[1:0] = 00
42
NOTE 1: Defined as skew between outputs at the same supply voltages and with equal load conditions.
Measured at VCCO/2.
NOTE 2: Please refer to the Phase Noise Plot.
NOTE 3: This parameter is defined in accordance with JEDEC Standard 65.
odc
843004AGI
ps
Output Duty Cycle
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5
600
ps
52
58
%
%
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
TYPICAL PHASE NOISE AT 53.125MHZ AT 3.3V
➤
0
-10
-20
Fibre Channel Jitter Filter
-30
-40
53.125MHz
-50
RMS Phase Jitter (Random)
637Khz to 5MHz = 0.49ps (typical)
-70
-80
-90
-100
Raw Phase Noise Data
-110
-120
➤
NOISE POWER dBc
Hz
-60
-130
-140
-150
➤
-160
-170
-180
Phase Noise Result by adding
Fibre Channel Filter to raw data
-190
100
1k
10k
100k
1M
10M
100M
OFFSET FREQUENCY (HZ)
TYPICAL PHASE NOISE AT 212.5MHZ AT 3.3V
➤
0
-10
-20
Fibre Channel Jitter Filter
-30
-40
212.5MHz
-50
RMS Phase Jitter (Random)
2.55Mhz to 20MHz = 0.47ps (typical)
-70
-80
-90
Raw Phase Noise Data
-100
-110
➤
NOISE POWER dBc
Hz
-60
-120
-130
-140
-150
➤
-160
-170
-180
-190
100
1k
10k
Phase Noise Result by adding
Fibre Channel Filter to raw data
100k
1M
10M
100M
OFFSET FREQUENCY (HZ)
843004AGI
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6
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
PARAMETER MEASUREMENT INFORMATION
2V
2V
Qx
V CC,
VCCA, VCCO
SCOPE
LVPECL
SCOPE
Qx
V CC,
VCCA, VCCO
LVPECL
nQx
nQx
VEE
VEE
-1.3V ± 0.33V
-0.5V ± 0.125V
3.3V CORE/3.3V OUTPUT LOAD AC TEST CIRCUIT
2.5V CORE/2.5V OUTPUT LOAD AC TEST CIRCUIT
Phase Noise Plot
Noise Power
nQx
Qx
nQy
Phase Noise Mask
Qy
t sk(o)
f1
Offset Frequency
f2
RMS Jitter = Area Under the Masked Phase Noise Plot
OUTPUT SKEW
RMS PHASE JITTER
nQ0:nQ3
80%
80%
Q0:Q3
VSW I N G
Clock
Outputs
Pulse Width
20%
20%
tR
t
PERIOD
tF
odc =
t PW
t PERIOD
OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD
OUTPUT RISE/FALL TIME
843004AGI
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REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
APPLICATION INFORMATION
POWER SUPPLY FILTERING TECHNIQUES
As in any high speed analog circuitry, the power supply pins
are vulnerable to random noise. The ICS843004I 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 VCCA.
3.3V or 2.5V
VCC
.01µF
10Ω
VCCA
.01µF
10µF
FIGURE 1. POWER SUPPLY FILTERING
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 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.
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 2A. LVPECL OUTPUT TERMINATION
843004AGI
125Ω
84Ω
FIGURE 2B. LVPECL OUTPUT TERMINATION
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REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
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Systems, Inc.
TERMINATION
FOR
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
2.5V LVPECL OUTPUT
Figure 3A and Figure 3B show examples of termination for 2.5V
LVPECL driver. These terminations are equivalent to terminating 50Ω to VCC - 2V. For VCCO = 2.5V, the VCCO - 2V is very close to
ground level. The R3 in Figure 3B can be eliminated and the
termination is shown in Figure 3C.
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 3A. 2.5V LVPECL DRIVER TERMINATION EXAMPLE
FIGURE 3B. 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 3C. 2.5V LVPECL TERMINATION EXAMPLE
CRYSTAL INPUT INTERFACE
below were determined using a 26.5625MHz 18pF parallel
resonant crystal and were chosen to minimize the ppm error.
The ICS843004I has been characterized with 18pF parallel
resonant crystals. The capacitor values shown in Figure 4
XTAL_OUT
C1
33p
X1
18pF Parallel Crystal
XTAL_IN
C2
27p
ICS843004I
Figure 4. CRYSTAL INPUt INTERFACE
843004AGI
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9
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
LAYOUT GUIDELINE
Figure 5 shows a schematic example of the ICS843004I. An
example of LVEPCL termination is shown in this schematic. Additional LVPECL termination approaches are shown in the
LVPECL Termination Application Note. In this example, an 18pF
parallel resonant 26.5625MHz crystal is used. The C1=27pF
and C2=33pF are recommended for frequency accuracy. For
different board layout, the C1 and C2 may be slightly adjusted
for optimizing frequency accuracy.
3.3V
VCC
VCCA
R2
10
R3
133
R5
133
Zo = 50 Ohm
C3
10uF
C4
0.01u
+
VCC
VCCO
C6
0.1u
To Logic
Input
pins
To Logic
Input
pins
RD1
Not Install
RD2
1K
U1
ICS843004
XTAL_OUT
XTAL_IN
VEE
TEST_CLK
nXTAL_SEL
VCC
VEE
nQ3
Q3
VCCO
Q2
nQ2
RU2
Not Install
RU1
1K
-
R4
82.5
F_SEL1
VCC
F_SEL0
VCCA
NC
nPLL_SEL
MR
nQ0
Q0
VCCO
Q1
nQ1
Set Logic
Input to
'0'
VDD
VCC=3.3V
R6
82.5
3.3V
VCCO=3.3V
R7
133
13
14
15
16
17
18
19
20
21
22
23
24
Set Logic
Input to
'1'
VDD
Zo = 50 Ohm
C7
0.1u
12
11
10
9
8
7
6
5
4
3
2
1
Logic Control Input Examples
R9
133
Zo = 50 Ohm
X1
26.5625MHz
18pF
Zo = 50 Ohm
C9
0.1u
C1
27pF
VCCO
C2
33pF
VCC
+
R8
82.5
-
R10
82.5
C8
0.1u
FIGURE 5. ICS843004I SCHEMATIC EXAMPLE
843004AGI
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10
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
POWER CONSIDERATIONS
This section provides information on power dissipation and junction temperature for the ICS843004I.
Equations and example calculations are also provided.
1. Power Dissipation.
The total power dissipation for the ICS843004I 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 * 130mA = 450.45mW
Power (outputs)MAX = 30mW/Loaded Output pair
If all outputs are loaded, the total power is 4 * 30mW = 120mW
Total Power_MAX (3.465V, with all outputs switching) = 450.45mW + 120mW = 570.45mW
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 1 meter per second and a multi-layer board, the appropriate value is 65°C/W per Table 6 below.
Therefore, Tj for an ambient temperature of 85°C with all outputs switching is:
85°C + 0.571W * 65°C/W = 122.1°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 (single layer or multi-layer).
TABLE 6. THERMAL RESISTANCE θJA
FOR
24-PIN TSSOP, FORCED CONVECTION
θJA by Velocity (Meters per Second)
Multi-Layer PCB, JEDEC Standard Test Boards
843004AGI
0
1
2.5
70°C/W
65°C/W
62°C/W
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11
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
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.
VCCO
Q1
VOUT
RL
50
VCCO - 2V
FIGURE 6. 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.
CC
•
For logic high, VOUT = V
OH_MAX
(V
CCO_MAX
•
-V
OH_MAX
OL_MAX
CCO_MAX
-V
OL_MAX
CC_MAX
– 0.9V
) = 0.9V
For logic low, VOUT = V
(V
=V
=V
CC_MAX
– 1.7V
) = 1.7V
Pd_H is power dissipation when the output drives high.
Pd_L is the power dissipation when the output drives low.
))/R ] * (V
Pd_H = [(V
– (V
- 2V))/R ] * (V
-V
) = [(2V - (V
-V
-V
)=
OH_MAX
CC_MAX
CC_MAX
OH_MAX
OH_MAX
CC_MAX
OH_MAX
L
CC_MAX
L
[(2V - 0.9V)/50Ω] * 0.9V = 19.8mW
Pd_L = [(V
OL_MAX
– (V
CC_MAX
- 2V))/R ] * (V
L
CC_MAX
-V
OL_MAX
) = [(2V - (V
CC_MAX
-V
OL_MAX
))/R ] * (V
L
CC_MAX
-V
OL_MAX
)=
[(2V - 1.7V)/50Ω] * 1.7V = 10.2mW
Total Power Dissipation per output pair = Pd_H + Pd_L = 30mW
843004AGI
www.icst.com/products/hiperclocks.html
12
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
RELIABILITY INFORMATION
TABLE 7. 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 ICS843004I is: 2578
843004AGI
www.icst.com/products/hiperclocks.html
13
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
PACKAGE OUTLINE - G SUFFIX
FOR
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
24 LEAD TSSOP
TABLE 8. PACKAGE DIMENSIONS
SYMBOL
Millimeters
Minimum
N
A
Maximum
24
--
1.20
A1
0.05
0.15
A2
0.80
1.05
b
0.19
0.30
c
0.09
0.20
D
7.70
7.90
E
E1
6.40 BASIC
4.30
e
4.50
0.65 BASIC
L
0.45
0.75
α
0°
8°
aaa
--
0.10
Reference Document: JEDEC Publication 95, MO-153
843004AGI
www.icst.com/products/hiperclocks.html
14
REV. A FEBRUARY 11, 2005
ICS843004I
Integrated
Circuit
Systems, Inc.
FEMTOCLOCKS™ CRYSTAL-TO3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
TABLE 9. ORDERING INFORMATION
Part/Order Number
Marking
Package
Shipping Packaging
Temperature
ICS843004AGI
ICS843004AGI
24 Lead TSSOP
tube
-40°C to 85°C
ICS843004AGIT
ICS843004AGI
24 Lead TSSOP
2500 tape & reel
-40°C to 85°C
ICS843004AGILF
TBD
24 Lead "Lead Free" TSSOP
tube
-40°C to 85°C
ICS843004AGILFT
TBD
24 Lead "Lead Free" TSSOP
2500 tape & reel
-40°C to 85°C
The aforementioned trademark, HiPerClockS™ and FEMTOCLOCKS™ is a trademark 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 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.
843004AGI
www.icst.com/products/hiperclocks.html
15
REV. A FEBRUARY 11, 2005