ICS ICS8521BYILFT

PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
GENERAL DESCRIPTION
FEATURES
The ICS8521I is a low skew, 1-to-9 Differentialto-HSTL Fanout Buffer and a member of the
HiPerClockS™
HiPerClockS™family of High Performance Clock
Solutions from ICS. The ICS8521I has two selectable clock inputs. The CLK, nCLK pair can
accept most standard differential input levels. The PCLK,
nPCLK pair can accept LVPECL, CML, or SSTL input levels.
The clock enable is internally synchronized to eliminate runt
pulses on the outputs during asynchronous assertion/
deassertion of the clock enable pin.
• Nine HSTL outputs
Guaranteed output skew, part-to-part skew and crossover
voltage characteristics make the ICS8521I ideal for today’s
most advanced applications, such as IA64 and static RAMs.
• Part-to-part skew: 200ps (typical)
ICS
• Selectable differential CLK, nCLK or LVPECL clock inputs
• CLK, nCLK pair can accept the following differential
input levels: LVPECL, LVDS, HSTL, SSTL, HCSL
• PCLK, nPCLK supports the following input types:
LVPECL, CML, SSTL
• Maximum output frequency: 500MHz
• Output skew: 25ps (typical)
• Propagation delay: 1.3ns (typical)
• VOH = 1.4V (maximum)
• 3.3V core, 1.8V output operating supply voltages
• -40°C to 85°C ambient operating temperature
• Available in both standard and lead-free RoHS
compliant packages
BLOCK DIAGRAM
PIN ASSIGNMENT
VDDO
nQ2
Q2
nQ1
Q1
nQ0
Q0
VDDO
D
CLK_EN
Q
CLK
nCLK
PCLK
nPCLK
CLK_SEL
LE
0
1
32 31 30 29 28 27 26 25
Q0
nQ0
VDD
CLK
nCLK
CLK_SEL
PCLK
nPCLK
GND
CLK_EN
Q1
nQ1
Q2
nQ2
Q3
nQ3
1
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
ICS8521I
VDDO
Q3
nQ3
Q4
nQ4
Q5
nQ5
VDDO
9 1 0 1 1 1 2 1 3 1 4 1 5 16
VDDO
Q6
nQ6
Q7
nQ7
Q8
nQ8
VDDO
Q4
nQ4
Q5
nQ5
32-Lead LQFP
7mm x 7mm x 1.4mm package body
Y Package
Top View
Q6
nQ6
Q7
nQ7
Q8
nQ8
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.
8521BYI
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1
REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
TABLE 1. PIN DESCRIPTIONS
Number
Name
1
VDD
Type
Description
Power
Power supply pin.
2
CLK
Input
Pulldown
3
nCLK
Input
Pullup
4
CLK_SEL
Input
Pulldown
5
PCLK
Input
Pulldown
6
nPCLK
Input
Pullup
7
GND
Power
8
CLK_EN
Input
Pullup
Non-inver ting differential clock input.
Inver ting differential clock input.
Clock select input. When HIGH, selects PCLK, nPCLK inputs.
When LOW, selects CLK, nCLK. LVTTL / LVCMOS interface levels.
Non-inver ting differential LVPECL clock input.
Inver ting differential LVPECL clock input.
Power supply ground.
Synchronizing clock enable. When HIGH, clock outputs follow
clock input. When LOW, Q outputs are forced low, nQ outputs
are forced high. LVCMOS /LVTTL interface levels.
9, 16, 17,
24, 25, 32
10, 11
VDDO
Power
Output supply pins.
nQ8, Q8
Output
Differential output pair. HSTL interface levels.
12, 13
nQ7, Q7
Output
Differential output pair. HSTL interface levels.
14, 15
nQ6, Q6
Output
Differential output pair. HSTL interface levels.
18, 19
nQ5, Q5
Output
Differential output pair. HSTL interface levels.
2 0, 21
nQ4, Q4
Output
Differential output pair. HSTL interface levels.
22, 23
nQ3 Q3
Output
Differential output pair. HSTL interface levels.
26, 27
nQ2, Q2
Output
Differential output pair. HSTL interface levels.
28, 29
nQ1, Q1
Output
Differential output pair. HSTL interface levels.
30, 31
nQ0, Q0
Output
Differential output pair. HSTL 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
Test Conditions
Minimum
Typical
Maximum
Units
CIN
Input Capacitance
4
pF
RPULLUP
Input Pullup Resistor
51
kΩ
RPULLDOWN
Input Pulldown Resistor
51
kΩ
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REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
TABLE 3A. CONTROL INPUT FUNCTION TABLE
Inputs
CLK_EN
CLK_SEL
Outputs
Selected Sourced
Q0:Q8
nQ0:nQ8
0
0
CLK, nCLK
Disabled; LOW
Disabled; HIGH
0
1
PCLK, nPCLK
Disabled; LOW
Disabled; HIGH
1
0
CLK, nCLK
Enabled
Enabled
1
1
PCLK, nPCLK
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 CLK, nCLK and PCLK, nPCLK inputs as described
in Table 3B.
Enabled
Disabled
nCLK, nPCLK
CLK, PCLK
CLK_EN
nQ0:nQ8
Q0:Q8
FIGURE 1. CLK_EN TIMING DIAGRAM
TABLE 3B. CLOCK INPUT FUNCTION TABLE
Inputs
Outputs
CLK or PCLK
nCLK or nPCLK
Q0:Q8
nQ0:nQ8
0
1
LOW
HIGH
Input to Output Mode
Polarity
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".
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3
REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VDD
4.6V
Inputs, VI
-0.5V to VDD + 0.5 V
Outputs, VO
-0.5V to VDDO + 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, VDD = 3.3V±5%, VDDO = 1.8V±0.2V, TA = -40°C TO 85°C
Symbol
Parameter
Test Conditions
Minimum
Typical
Maximum
VDD
VDDO
IDD
Power Supply Current
Power Supply Voltage
3.135
3.3
3.465
V
Output Supply Voltage
1.6
1.8
2.0
V
60
Units
mA
TABLE 4B. LVCMOS/LVTTL DC CHARACTERISTICS, VDD = 3.3V±5%, VDDO = 1.8V±0.2V, TA = -40°C TO 85°C
Symbol
Parameter
VIH
Input High Voltage
CLK_EN, CLK_SEL
2
VDD + 0.3
V
VIL
Input Low Voltage
CLK_EN, CLK_SEL
-0.3
0.8
V
IIH
Input High Current
5
µA
IIL
Input Low Current
Test Conditions
CLK_EN
Minimum
Typical
VIN = VDD = 3.465V
Maximum
Units
CLK_SEL
VIN = VDD = 3.465V
CLK_EN
VIN = 0V, VDD = 3.465V
-150
µA
CLK_SEL
VIN = 0V, VDD = 3.465V
-5
µA
150
µA
TABLE 4C. DIFFERENTIAL DC CHARACTERISTICS, VDD = 3.3V±5%, VDDO = 1.8V±0.2V, TA = -40°C TO 85°C
Symbol
Parameter
IIH
Input High Current
IIL
Input Low Current
Test Conditions
Minimum
Typical
Units
CLK
VIN = VDD = 3.465V
150
µA
nCLK
VIN = VDD = 3.465V
5
µA
CLK
VIN = 0V, VDD = 3.465V
-5
nCLK
VIN = 0V, VDD = 3.465V
-150
Peak-to-Peak Input Voltage
0.15
Common Mode Input Voltage;
VCMR
0.5
NOTE 1, 2
NOTE 1: For single ended applications, the maximum input voltage for CLK and nCLK is VDD + 0.3V.
NOTE 2: Common mode voltage is defined as VIH.
VPP
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4
µA
µA
1.3
V
VDD - 0.85
V
REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
TABLE 4D. LVPECL DC CHARACTERISTICS, VDD = 3.3V±5%, VDDO = 1.8V±0.2V, TA = -40°C TO 85°C
Symbol
IIH
IIL
Parameter
Input High Current
Input Low Current
Test Conditions
PCLK
Minimum
Typical
Maximum
Units
150
µA
VDD = VIN = 3.465V
nPCLK
VDD = VIN = 3.465V
PCLK
VDD = 3.465V, VIN = 0V
-5
5
µA
nPCLK
VDD = 3.465V, VIN = 0V
-150
µA
VPP
Peak-to-Peak Input Voltage
0.3
Common Mode Input Voltage;
VCMR
1.5
NOTE 1, 2
NOTE 1: Common mode voltage is defined as VIH.
NOTE 2: For single ended applications, the maximum input voltage for PCLK and nPCLK is VDD + 0.3V.
µA
1
V
VDD
V
TABLE 4E. HSTL DC CHARACTERISTICS, VDD = 3.3V±5%, VDDO = 1.8V±0.2V, TA = -40°C TO 85°C
Symbol Parameter
Output High Voltage;
VOH
NOTE 1
Output Low Voltage;
VOL
NOTE 1
VOX
Test Conditions
Output Crossover Voltage
Minimum
Maximum
Units
1.0
1.4
V
0
0.4
V
40% x (VOH - VOL) + VOL
60% x (VOH - VOL) + VOL
V
0.6
1.1
V
Peak-to-Peak
Output Voltage Swing
NOTE 1: Outputs terminated with 50Ω to ground.
VSWING
Typical
TABLE 5. AC CHARACTERISTICS, VDD = 3.3V±5%, VDDO = 1.8V±0.2V, TA = -40°C TO 85°C
Symbol
Parameter
fMAX
Output Frequency
tPD
Propagation Delay; NOTE 1
t sk(o)
Output Skew; NOTE 2, 4
t sk(pp)
Par t-to-Par t Skew; NOTE 3, 4
tR / tF
Output Rise/Fall Time
Test Conditions
Minimum
IJ 250MHz
Typical
Units
500
MHz
1.3
ns
25
ps
200
20% to 80% @ 50MHz
300
odc
Output Duty Cycle
50
All parameters measured at 250MHz unless noted otherwise.
NOTE 1: Measured from the differential input crossing point to the differential output crossing point.
Measured from VDD/2 to the output differential crossing point for single ended input levels.
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.
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5
ps
700
ps
%
REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
PARAMETER MEASUREMENT INFORMATION
3.3V ± 5%
1.8V ± 0.2V
VDD
V DD
Qx
SCOPE
nCLK,
nPCLK
VDDO
V
HSTL
V
Cross Points
PP
CMR
CLK,
PCLK
nQx
GND
GND = 0V
3.3V CORE/1.8V OUTPUT LOAD AC TEST CIRCUIT
DIFFERENTIAL INPUT LEVEL
PART 1
nQx
nQx
Qx
Qx
PART 2
nQy
nQy
Qy
Qy
tsk(pp)
tsk(o)
PART-TO-PART SKEW
OUTPUT SKEW
nCLK,
nPCLK
80%
CLK,
PCLK
80%
VOD
Clock
Outputs
nQ0:nQ8
20%
20%
tR
tF
Q0:Q8
tPD
OUTPUT RISE/FALL TIME
PROPAGATION DELAY
nQ0:nQ8
Q0:Q8
t PW
t
odc =
PERIOD
t PW
x 100%
t PERIOD
OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD
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REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
APPLICATION INFORMATION
WIRING THE DIFFERENTIAL INPUT TO ACCEPT SINGLE ENDED LEVELS
Figure 2 shows how the differential input can be wired to accept
single ended levels. The reference voltage V_REF = VDD/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 VDD = 3.3V, V_REF should be 1.25V
and R2/R1 = 0.609.
VDD
R1
1K
CLK_IN
+
V_REF
C1
0.1uF
R2
1K
FIGURE 2. SINGLE ENDED SIGNAL DRIVING DIFFERENTIAL INPUT
RECOMMENDATIONS FOR UNUSED INPUT AND OUTPUT PINS
INPUTS:
OUTPUTS:
CLK/nCLK INPUT:
For applications not requiring the use of the differential input,
both CLK and nCLK can be left floating. Though not required,
but for additional protection, a 1kΩ resistor can be tied from
CLK to ground.
HSTL OUTPUT
All unused LVHSTL 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.
PCLK/nPCLK INPUT:
For applications not requiring the use of a differential input,
both the PCLK and nPCLK pins can be left floating. Though
not required, but for additional protection, a 1kΩ resistor can
be tied from PCLK 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.
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REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
DIFFERENTIAL CLOCK INPUT INTERFACE
The CLK /nCLK accepts LVDS, LVPECL, HSTL, SSTL, HCSL
and other differential signals. Both VSWING and VOH must meet the
VPP and VCMR input requirements. Figures 3A to 3E 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 3A, the input termination applies for ICS
HiPerClockS HSTL drivers. If you are using an HSTL 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 3A. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
ICS HIPERCLOCKS HSTL DRIVER
FIGURE 3B. 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 3C. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
3.3V LVPECL DRIVER
FIGURE 3D. 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 3E. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
3.3V LVPECL DRIVER WITH AC COUPLE
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REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
LVPECL CLOCK INPUT INTERFACE
gested here are examples only. If the driver is from another
vendor, use their termination recommendation. Please consult with the vendor of the driver component to confirm the
driver termination requirements.
The PCLK /nPCLK accepts LVPECL, CML, SSTL and other
differential signals. Both VSWING and VOH must meet the VPP
and VCMR input requirements. Figures 4A to 4D show interface examples for the HiPerClockS PCLK/nPCLK input driven
by the most common driver types. The input interfaces sug-
2.5V
3.3V
3.3V
3.3V
2.5V
3.3V
R1
50
CML
R3
120
R2
50
SSTL
Zo = 50 Ohm
R4
120
Zo = 60 Ohm
PCLK
PCLK
Zo = 60 Ohm
Zo = 50 Ohm
nPCLK
nPCLK
HiPerClockS
PCLK/nPCLK
R1
120
FIGURE 4A. HIPERCLOCKS PCLK/NPCLK INPUT DRIVEN
BY A CML DRIVER
HiPerClockS
PCLK/nPCLK
R2
120
FIGURE 4B. HIPERCLOCKS PCLK/NPCLK INPUT DRIVEN
BY AN SSTL DRIVER
3.3V
3.3V
3.3V
3.3V
3.3V
R3
125
R4
125
Zo = 50 Ohm
LVDS_Driv er
Zo = 50 Ohm
CLK
CLK
R1
100
Zo = 50 Ohm
nCLK
LVPECL
R1
84
nCLK
Receiv er
Zo = 50 Ohm
HiPerClockS
Input
R2
84
FIGURE 4C. HIPERCLOCKS PCLK/NPCLK INPUT DRIVEN
BY A 3.3V LVPECL DRIVER
FIGURE 4D. HIPERCLOCKS PCLK/NPCLK INPUT DRIVEN
BY A 3.3V LVDS DRIVER
3.3V
3.3V
3.3V
3.3V LVPECL
Zo = 50 Ohm
C1
Zo = 50 Ohm
C2
R3
84
R4
84
PCLK
nPCLK
R5
100 - 200
R6
100 - 200
R1
125
HiPerClockS
PCLK/nPCLK
R2
125
FIGURE 4E. HIPERCLOCKS PCLK/NPCLK INPUT DRIVEN
BY A 3.3V LVPECL DRIVER WITH AC COUPLE
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REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
POWER CONSIDERATIONS
This section provides information on power dissipation and junction temperature for the ICS8521I.
Equations and example calculations are also provided.
1. Power Dissipation.
The total power dissipation for the ICS8521I 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.
NOTE: Please refer to Section 3 for details on calculating power dissipated in the load.
•
•
Power (core)MAX = VDD_MAX * IDD_MAX = 3.465V * 60mA = 208mW
Power (outputs)MAX = 32.8mW/Loaded Output pair
If all outputs are loaded, the total power is 9 * 32.8mW = 295.2mW
Total Power_MAX (3.465V, with all outputs switching) = 208mW + 295.2mW = 503.2mW
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 + 0.503W * 42.1°C/W = 106.2°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 6. Thermal Resistance θJA for 32-pin LQFP, Forced Convection
θJA by Velocity (Linear Feet per Minute)
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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REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
3. Calculations and Equations.
The purpose of this section is to derive the power dissipated into the load.
LVHSTL output driver circuit and termination are shown in Figure 5.
VDDO
Q1
VOUT
RL
50Ω
FIGURE 5. HSTL DRIVER CIRCUIT
AND
TERMINATION
To calculate worst case power dissipation into the load, use the following equations which assume a 50Ω load.
Pd_H is power dissipation when the output drives high.
Pd_L is the power dissipation when the output drives low.
Pd_H = (V
/R ) * (V
OH_MIN
Pd_L = (V
L
DDO_MAX
/R ) * (V
OL_MAX
L
-V
)
OH_MIN
-V
DDO_MAX
)
OL_MAX
Pd_H = (1.0V/50Ω) * (2V - 1.0V) = 20mW
Pd_L = (0.4V/50Ω) * (2V - 0.4V) = 12.8mW
Total Power Dissipation per output pair = Pd_H + Pd_L = 32.8mW
8521BYI
www.icst.com/products/hiperclocks.html
11
REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
RELIABILITY INFORMATION
TABLE 7. θJAVS. AIR FLOW TABLE FOR 32 LEAD LQFP
θJA by Velocity (Linear Feet per Minute)
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 ICS8521I is: 944
8521BYI
www.icst.com/products/hiperclocks.html
12
REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
PACKAGE OUTLINE - Y SUFFIX 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.
e
0.80 BASIC
L
0.45
0.60
0.75
θ
0°
--
7°
ccc
--
--
0.10
Reference Document: JEDEC Publication 95, MS-026
8521BYI
www.icst.com/products/hiperclocks.html
13
REV. A NOVEMBER 17, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8521I
LOW SKEW, 1-TO-9
DIFFERENTIAL-TO-HSTL FANOUT BUFFER
TABLE 9. ORDERING INFORMATION
Part/Order Number
Marking
Package
Shipping Packaging
Temperature
ICS8521BYI
ICS8521BYI
32 Lead LQFP
tray
-40°C to 85°C
ICS8521BYIT
ICS8521BYI
32 Lead LQFP
1000 tape & reel
-40°C to 85°C
ICS8521BYILF
ICS8521BYILF
32 Lead "Lead-Free" LQFP
tray
-40°C to 85°C
ICS8521BYILFT
ICS8521BYILF
32 Lead "Lead-Free" LQFP
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.
8521BYI
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14
REV. A NOVEMBER 17, 2005