ICS ICS85310AYI-11LF

Integrated
Circuit
Systems, Inc.
ICS85310I-11
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
GENERAL DESCRIPTION
FEATURES
The ICS85310I-11 is a low skew, high performance 1-to-10 Differential-to-2.5V/3.3V ECL/
HiPerClockS™
LVPECL Fanout Buffer and a member of the
HiPerClockS™ family of High Perfor mance
Clock Solutions from ICS. The CLKx, nCLKx
pairs can accept most standard differential input levels. The
ICS85310I-11 is characterized to operate from either a
2.5V or a 3.3V power supply. Guaranteed output and partto-part skew characteristics make the ICS85310I-11 ideal
for those clock distribution applications demanding well defined performance and repeatability.
• 10 differential 2.5V/3.3V LVPECL / ECL outputs
ICS
• 2 selectable differential input pairs
• CLKx, nCLKx pairs can accept the following differential
input levels: LVDS, LVPECL, LVHSTL, SSTL, HCSL
• Maximum output frequency: 700MHz
• Translates any single ended input signal to 3.3V
LVPECL levels with resistor bias on nCLK input
• Output skew: 30ps (typical)
• Part-to-part skew: 140ps (typical)
• Propagation delay: 2ns (typical)
• Additive phase jitter, RMS: <0.13ps (typical)
• LVPECL mode operating voltage supply range:
VCC = 2.375V to 3.8V, VEE = 0V
• ECL mode operating voltage supply range:
VCC = 0V, VEE = -2.375V to -3.8V
• -40°C to 85°C ambient operating temperature
• Lead-Free package fully RoHS complaint
BLOCK DIAGRAM
PIN ASSIGNMENT
VCCO
nQ2
Q2
Q1
nQ1
nQ1
1
Q1
CLK1
nCLK1
nQ0
Q0
nQ0
Q0
0
VCCO
CLK0
nCLK0
32 31 30 29 28 27 26 25
Q2
nQ2
CLK_SEL
CLK_EN
VCC
1
24
Q3
CLK_SEL
2
23
nQ3
CLK0
3
22
Q4
nCLK0
4
21
nQ4
Q4
nQ4
CLK_EN
5
20
Q5
CLK1
6
19
nQ5
Q5
nQ5
nCLK1
7
18
Q6
VEE
8
17
nQ6
Q3
nQ3
D
Q
LE
Q6
nQ6
9 10 11 12 13 14 15 16
VCCO
Q7
nQ7
Q8
nQ8
Q9
nQ9
VCCO
Q7
nQ7
32-Lead LQFP
7mm x 7mm x 1.4mm package body
Y Package
Top View
Q8
nQ8
Q9
nQ9
85310AYI-11
ICS85310I-11
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1
REV. E JULY 7, 2005
ICS85310I-11
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
TABLE 1. PIN DESCRIPTIONS
Number
Name
1
VCC
Power
Type
2
CLK_SEL
Input
Description
Core supply pin.
Clock select input. When HIGH, selects CLK1, nCLK1 inputs. When LOW,
Pulldown
selects CLK0, nCLK0 inputs. LVCMOS / LVTTL interface levels.
Pulldown Non-inver ting differential clock input.
3
CLK0
Input
4
nCLK0
Input
5
CLK_EN
Input
6
CLK1
Input
7
nCLK1
Input
8
VEE
Power
Negative supply pin.
9, 16, 25, 32
VCCO
Power
Output supply pins.
Pullup
Inver ting differential clock input.
Synchronizing clock enable. When HIGH, clock outputs follow clock input.
When LOW, Q outputs are forced low, nQ outputs are forced high.
Pullup
LVCMOS / LVTTL interface levels.
Pulldown Non-inver ting differential clock input.
Pullup
Inver ting differential clock input.
10, 11
nQ9, Q9
Output
Differential output pair. LVPECL interface levels.
1 2, 13
nQ8, Q8
Output
Differential output pair. LVPECL interface levels.
14, 15
nQ7, Q7
Output
Differential output pair. LVPECL interface levels.
17, 18
nQ6, Q6
Output
Differential output pair. LVPECL interface levels.
19, 20
nQ5, Q5
Output
Differential output pair. LVPECL interface levels.
21, 22
nQ4, Q4
Output
Differential output pair. LVPECL interface levels.
23, 24
nQ3, Q3
Output
Differential output pair. LVPECL interface levels.
26, 27
nQ2, Q2
Output
Differential output pair. LVPECL interface levels.
28, 29
nQ1, Q1
Output
Differential output pair. LVPECL interface levels.
30, 31
nQ0, Q0
Output
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
85310AYI-11
Test Conditions
Minimum
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2
Typical
Maximum
Units
REV. E JULY 7, 2005
Integrated
Circuit
Systems, Inc.
ICS85310I-11
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
TABLE 3A. CONTROL INPUT FUNCTION TABLE
Inputs
Outputs
CLK_EN
Selected Source
Q0:Q9
Q0:Q9
0
CLK0, nCLK0
Disabled; LOW
Disabled; HIGH
1
CLK1, nCLK1
Enabled
Enabled
After CLK_EN switches, the clock outputs are disabled or enabled following a rising and falling input clock edge
as shown in Figure 1.
In the active mode, the state of the outputs are a function of the CLK0, nCLK0 and CLK1, nCLK1 inputs as described
in Table 3B.
Enabled
Disabled
CLK0, nCLK0
CLK1, CLK1
CLK_EN
nQ0:nQ9
Q0:Q9
FIGURE 1. CLK_EN TIMING DIAGRAM
TABLE 3B. CLOCK INPUT FUNCTION TABLE
Inputs
CLK0 or CLK1
Outputs
nCLK0 or nCLK1
Q0:Q9
nQ0:Q9
Input to Output Mode
Polarity
0
1
LOW
HIGH
Differential to Differential
Non Inver ting
1
0
HIGH
LOW
Differential to Differential
Non Inver ting
0
Biased; NOTE 1
LOW
HIGH
Single Ended to Differential
Non Inver ting
1
Biased; NOTE 1
HIGH
LOW
Single Ended to Differential
Non Inver ting
Biased; NOTE 1
0
HIGH
LOW
Single Ended to Differential
Inver ting
Biased; NOTE 1
1
LOW
HIGH
Single Ended to Differential
Inver ting
NOTE 1: Please refer to the Application Information, "Wiring the Differential Input to Accept Single Ended Levels".
85310AYI-11
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REV. E JULY 7, 2005
ICS85310I-11
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VCC
4.6V
Inputs, VCC
-0.5V to VCC + 0.5 V
Outputs, VCCO
-0.5V to VCCO + 0.5V
Package Thermal Impedance, θJA
47.9°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 4A. POWER SUPPLY DC CHARACTERISTICS, VCC = VCCO = 2.375V TO 3.8V, TA = -40°C TO 85°C
Symbol
Parameter
Minimum
Typical
Maximum
Units
VCC
Core Supply Voltage
Test Conditions
2.375
3.3
3.8
V
VCCO
Output Supply Voltage
2.375
3.3
IEE
Power Supply Current
3.8
V
120
mA
Table 4B. LVCMOS/LVTTL DC Characteristics, VCC = VCCO = 2.375V TO 3.8V, TA = -40°C to 85°C
Symbol
Parameter
VIH
Input High Voltage
VIL
Input Low Voltage
IIH
Input High Current
IIL
Input Low Current
Test Conditions
Minimum
Typical
Maximum
Units
2
VCC + 0.3
V
-0.3
0.8
V
CLK_SEL,
CLK_EN
CLK_SEL,
CLK_EN
CLK_EN
VCC = VIN = 3.8V
5
µA
CLK_SEL
VCC = VIN = 3.8V
150
µA
CLK_EN
VCC = 3.8V, VIN = 0V
-150
µA
CLK_SEL
VCC = 3.8V, VIN = 0V
-5
µA
TABLE 4C. DIFFERENTIAL DC CHARACTERISTICS, VCC = VCCO = 2.375V TO 3.8V, TA = -40°C TO 85°C
Symbol
Parameter
Maximum
Units
CLK0, CLK1
Test Conditions
VCC = VIN = 3.8V
150
µA
nCLK0, nCLK1
VCC = VIN = 3.8V
5
µA
IIH
Input High Current
IIL
Input Low Current
VPP
Peak-to-Peak Input Voltage
Minimum
Typical
CLK0, CLK1
VCC = 3.8V, VIN = 0V
-5
µA
nCLK0, nCLK1
VCC = 3.8V, VIN = 0V
-150
µA
0.15
1.3
VCMR
Common Mode Input Voltage; NOTE 1, 2
VEE + 0.5
VCC - 0.85
NOTE 1: Common mode voltage is defined as VIH.
NOTE 2: For single ended applications, the maximum input voltage for CLK0, nCLK0 and CLK1, nCLK1 is VCC + 0.3V.
85310AYI-11
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4
V
V
REV. E JULY 7, 2005
Integrated
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Systems, Inc.
ICS85310I-11
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
TABLE 4D. LVPECL DC CHARACTERISTICS, VCC = VCCO = 2.375V TO 3.8V, TA = -40°C TO 85°C
Symbol Parameter
Maximum
Units
VOH
Output High Voltage; NOTE 1
Test Conditions
Minimum
VCC - 1.4
Typical
VCC - 1.0
V
VOL
Output Low Voltage; NOTE 1
VCC - 2.0
VCC - 1.7
V
VSWING
Peak-to-Peak Output Voltage Swing
0.6
0.85
V
NOTE 1: Outputs terminated with 50Ω to VCCO - 2V.
TABLE 5. AC CHARACTERISTICS, VCC = VCCO = 2.375V TO 3.8V, TA = -40°C TO 85°C
Symbol
Parameter
fMAX
Output Frequency
tPD
Propagation Delay; NOTE 1
2
2.5
ns
tsk(o)
Output Skew; NOTE 2, 4
30
55
ps
tsk(pp)
140
340
ps
tR
Par t-to-Par t Skew; NOTE 3, 4
Buffer Additive Phase Jitter,
RMS; refer to Additive Phase
Jitter Section
Output Rise Time
20% to 80%
200
700
ps
tF
Output Fall Time
20% to 80%
200
700
ps
53
%
tjit
Test Conditions
Minimum
IJ 500MHz
Typical
Units
700
MHz
<0.13
odc
Output Duty Cycle
47
All parameters measured at 500MHz unless noted otherwise.
NOTE 1: Measured from the differential input crossing point to the differential output crossing point.
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: Defined as skew between outputs on different devices operating at the same supply voltages
and with equal load conditions. Using the same type of inputs on each device, the outputs are measured
at the differential cross points.
NOTE 4: This parameter is defined in accordance with JEDEC Standard 65.
85310AYI-11
Maximum
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5
ps
REV. E JULY 7, 2005
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Systems, Inc.
ICS85310I-11
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
ADDITIVE PHASE JITTER
the 1Hz band to the power in the fundamental. When the required offset is specified, the phase noise is called a dBc value,
which simply means dBm at a specified offset from the fundamental. By investigating jitter in the frequency domain, we get a
better understanding of its effects on the desired application over
the entire time record of the signal. It is mathematically possible
to calculate an expected bit error rate given a phase noise plot.
The spectral purity in a band at a specific offset from the fundamental compared to the power of the fundamental is called the
dBc Phase Noise. This value is normally expressed using a
Phase noise plot and is most often the specified plot in many
applications. Phase noise is defined as the ratio of the noise
power present in a 1Hz band at a specified offset from the fundamental frequency to the power value of the fundamental. This
ratio is expressed in decibels (dBm) or a ratio of the power in
0
-10
Additive Phase Jitter, RMS
-20
@ 155.52MHz = <0.13ps typical
-30
-40
-50
SSB PHASE NOISE dBc/HZ
-60
-70
-80
-90
-100
-110
-120
-130
-140
-150
-160
-170
-180
-190
100
1k
10k
100k
1M
10M
100M
OFFSET FROM CARRIER FREQUENCY (HZ)
vice meets the noise floor of what is shown, but can actually be
lower. The phase noise is dependant on the input source and
measurement equipment.
As with most timing specifications, phase noise measurements
have issues. The primary issue relates to the limitations of the
equipment. Often the noise floor of the equipment is higher than
the noise floor of the device. This is illustrated above. The de-
85310AYI-11
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ICS85310I-11
Integrated
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LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
PARAMETER MEASUREMENT INFORMATION
VCC, VCCO = 2V
Qx
VCC
SCOPE
nCLK0, nCLK1
LVPECL
V
Cross Points
PP
V
CMR
CLK0, CLK1
nQx
V EE
VEE = -0.375V to -1.8V
3.3V OUTPUT LOAD AC TEST CIRCUIT
DIFFERENTIAL INPUT LEVEL
nQx
PART 1
Qx
nQx
nQy
nQy
Qx
PART 2
Qy
Qy
tsk(pp)
tsk(o)
PART-TO-PART SKEW
OUTPUT SKEW
nCLK0,
nCLK1
80%
80%
CLK0,
CLK1
VSW I N G
Clock
Outputs
nQ0:nQ9
20%
20%
tF
tR
Q0:Q9
tPD
OUTPUT RISE/FALL TIME
PROPAGATION DELAY
nQ0:nQ9
Q0:Q9
t PW
t
odc =
PERIOD
t PW
x 100%
t PERIOD
OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD
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REV. E JULY 7, 2005
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Integrated
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LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
APPLICATION INFORMATION
WIRING THE DIFFERENTIAL INPUT TO ACCEPT SINGLE ENDED LEVELS
Figure 1 shows how the differential input can be wired to accept
single ended levels. The reference voltage V_REF ~ VCC/2 is
generated by the bias resistors R1, R2 and C1. This bias circuit
should be located as close as possible to the input pin. The ratio
of R1 and R2 might need to be adjusted to position the V_REF in
the center of the input voltage swing. For example, if the input
clock swing is only 2.5V and VCC = 3.3V, V_REF should be 1.25V
and R2/R1 = 0.609.
VCC
R1
1K
Single Ended Clock Input
CLKx
V_REF
nCLKx
C1
0.1u
R2
1K
FIGURE 2. SINGLE ENDED SIGNAL DRIVING DIFFERENTIAL INPUT
TERMINATION
FOR
3.3V LVPECL OUTPUTS
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.
The clock layout topology shown below is a typical termination for LVPECL outputs. 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, terminating
resistors (DC current path to ground) or current sources must
be used for functionality. These outputs are designed to drive
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
85310AYI-11
125Ω
84Ω
FIGURE 3B. LVPECL OUTPUT TERMINATION
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ICS85310I-11
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
TERMINATION FOR 2.5V LVPECL OUTPUTS
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 4A. 2.5V LVPECL DRIVER TERMINATION EXAMPLE
FIGURE 4B. 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
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LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
DIFFERENTIAL CLOCK INPUT INTERFACE
The CLK /nCLK accepts LVDS, LVPECL, LVHSTL, SSTL, HCSL
and other differential signals. Both VSWING and VOH must meet the
VPP and VCMR input requirements. Figures 5A to 5E show interface examples for the HiPerClockS CLK/nCLK input driven by
the most common driver types. The input interfaces suggested
here are examples only. Please consult with the vendor of the
driver component to confirm the driver termination requirements.
For example in Figure 5A, the input termination applies for ICS
HiPerClockS LVHSTL drivers. If you are using an LVHSTL driver
from another vendor, use their termination recommendation.
3.3V
3.3V
3.3V
1.8V
Zo = 50 Ohm
CLK
Zo = 50 Ohm
CLK
Zo = 50 Ohm
nCLK
Zo = 50 Ohm
LVPECL
nCLK
HiPerClockS
Input
LVHSTL
ICS
HiPerClockS
LVHSTL Driver
R1
50
R1
50
HiPerClockS
Input
R2
50
R2
50
R3
50
FIGURE 5A. HIPERCLOCKS CLK/nCLK INPUT DRIVEN
ICS HIPERCLOCKS LVHSTL DRIVER
FIGURE 5B. HIPERCLOCKS CLK/nCLK INPUT DRIVEN
3.3V LVPECL DRIVER
BY
3.3V
3.3V
3.3V
3.3V
3.3V
R3
125
BY
R4
125
Zo = 50 Ohm
LVDS_Driv er
Zo = 50 Ohm
CLK
CLK
R1
100
Zo = 50 Ohm
nCLK
LVPECL
R1
84
HiPerClockS
Input
nCLK
Receiv er
Zo = 50 Ohm
R2
84
FIGURE 5C. HIPERCLOCKS CLK/nCLK INPUT DRIVEN
3.3V LVPECL DRIVER
FIGURE 5D. HIPERCLOCKS CLK/nCLK INPUT DRIVEN
3.3V LVDS DRIVER
BY
BY
3.3V
3.3V
3.3V
LVPECL
Zo = 50 Ohm
C1
Zo = 50 Ohm
C2
R3
125
R4
125
CLK
nCLK
R5
100 - 200
R6
100 - 200
R1
84
HiPerClockS
Input
R2
84
R5,R6 locate near the driver pin.
FIGURE 5E. HIPERCLOCKS CLK/nCLK INPUT DRIVEN
3.3V LVPECL DRIVER WITH AC COUPLE
85310AYI-11
BY
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ICS85310I-11
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
POWER CONSIDERATIONS
This section provides information on power dissipation and junction temperature for the ICS85310I-11.
Equations and example calculations are also provided.
1. Power Dissipation.
The total power dissipation for the ICS85310I-11 is the sum of the core power plus the power dissipated in the load(s).
The following is the power dissipation for VCC = 3.8V, 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 = 3.8V * 120mA = 456mW
Power (outputs)MAX = 30.2mW/Loaded Output pair
If all outputs are loaded, the total power is 10 * 30.2mW = 302mW
Total Power_MAX (3.8V, with all outputs switching) = 456mW + 302mW = 758mW
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 42.1°C/W per Table 6 below.
Therefore, Tj for an ambient temperature of 85°C with all outputs switching is:
85°C + 0.758W * 42.1°C/W = 117°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
32-PIN LQFP, FORCED CONVECTION
θ by Velocity (Linear Feet per Minute)
JA
Single-Layer PCB, JEDEC Standard Test Boards
Multi-Layer PCB, JEDEC Standard Test Boards
0
200
500
67.8°C/W
47.9°C/W
55.9°C/W
42.1°C/W
50.1°C/W
39.4°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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DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
3. Calculations and Equations.
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.
CCO
•
For logic high, VOUT = V
OH_MAX
(V
CCO_MAX
•
-V
OH_MAX
OL_MAX
-V
Pd_H = [(V
– (V
CCO_MAX
OH_MAX
OL_MAX
CCO_MAX
– 1.0V
) = 1.0V
For logic low, VOUT = V
(V
=V
=V
CCO_MAX
– 1.7V
) = 1.7V
CCO_MAX
- 2V))/R ] * (V
CCO_MAX
L
-V
OH_MAX
) = [(2V - (V
CCO _MAX
-V
))/R ] * (V
OH_MAX
CCO _MAX
L
-V
)=
OH_MAX
[(2V - 1V)/50Ω] * 1V = 20.0mW
Pd_L = [(V
OL_MAX
– (V
CCO_MAX
- 2V))/R ] * (V
L
CCO_MAX
-V
OL_MAX
) = [(2V - (V
CCO_MAX
-V
OL_MAX
))/R ] * (V
L
CCO_MAX
-V
OL_MAX
)=
[(2V - 1.7V)/50Ω] * 1.7V = 10.2mW
Total Power Dissipation per output pair = Pd_H + Pd_L = 30.2mW
85310AYI-11
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12
REV. E JULY 7, 2005
Integrated
Circuit
Systems, Inc.
ICS85310I-11
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
RELIABILITY INFORMATION
TABLE 7.
θJAVS. AIR FLOW TABLE FOR 32 LEAD LQFP
θ by Velocity (Linear Feet per Minute)
JA
Single-Layer PCB, JEDEC Standard Test Boards
Multi-Layer PCB, JEDEC Standard Test Boards
0
200
500
67.8°C/W
47.9°C/W
55.9°C/W
42.1°C/W
50.1°C/W
39.4°C/W
NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs.
TRANSISTOR COUNT
The transistor count for ICS85310I-11 is: 1034
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REV. E JULY 7, 2005
ICS85310I-11
Integrated
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PACKAGE OUTLINE - Y SUFFIX
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
FOR
32 LEAD LQFP
TABLE 8. PACKAGE DIMENSIONS
JEDEC VARIATION
ALL DIMENSIONS IN MILLIMETERS
BBA
SYMBOL
MINIMUM
NOMINAL
MAXIMUM
32
N
A
--
--
1.60
A1
0.05
--
0.15
A2
1.35
1.40
1.45
b
0.30
0.37
0.45
c
0.09
--
0.20
D
9.00 BASIC
D1
7.00 BASIC
D2
5.60 Ref.
E
9.00 BASIC
E1
7.00 BASIC
E2
5.60 Ref.
0.80 BASIC
e
0.60
0.75
L
0.45
θ
0°
--
7°
ccc
--
--
0.10
Reference Document: JEDEC Publication 95, MS-026
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REV. E JULY 7, 2005
Integrated
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ICS85310I-11
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
TABLE 9. ORDERING INFORMATION
Part/Order Number
Marking
Package
Shipping Packaging
Temperature
ICS85310AYI-11
ICS85310AYI11
32 lead LQFP
tray
-40°C to 85°C
ICS85310AYI-11T
ICS85310AYI11
32 lead LQFP
1000 tape & reel
-40°C to 85°C
ICS85310AYI-11LF
ICS85310AI11L
32 lead LQFP, "Lead-Free"
tray
-40°C to 85°C
ICS85310AYI-11LFT
ICS85310AI11L
32 lead LQFP, "Lead-Free"
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.
The aforementioned trademark, HiPerClockS 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.
85310AYI-11
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REV. E JULY 7, 2005
Integrated
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Systems, Inc.
ICS85310I-11
LOW SKEW, 1-TO-10
DIFFERENTIAL-TO-2.5V/3.3V ECL/LVPECL FANOUT BUFFER
REVISION HISTORY SHEET
Rev
Table
Page
4
Description of Change
AC Characterisitics table - tPD row, revised value from 2.25ns Max. to
2.5ns Max.
Added Termination for LVPECL Outputs section.
Added LVPECL DC Characterisitics table.
Changed par t number from ICS85310-11 to ICS85310I-11 in title and all
subsequent areas throughout the datasheet.
Power Supply table - increased max. value for IEE to 120mA from 30mA max.
B
T5
5
4D
9
5
10
1
2
5
6
9
10
15
Power Considerations have re-adjusted to the increased IEE value.
Features Section - added Additive Phase Jitter bullet and Lead Free bullet.
Pin Characteristics Table - changed CIN 4pF max. to 4pF typical
AC Characteristics Table - added Additive Phase Jitter row.
Added Additive Phase Jitter Section.
Added Termination for 2.5V LVPECL Outputs.
Added Differential Clock Input Interface.
Ordering Information Table - added Lead-Free Par t Number and Note.
C
D
T4A
T2
T5
E
T9
85310AYI-11
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16
Date
4/29/02
5/29/02
7/25/02
10/23/02
7/7/05
REV. E JULY 7, 2005