ALSC ASM2I99446G-32-ET

ASM2I99446
July 2005
rev 0.4
2.5V and 3.3V LVCMOS Clock Distribution Buffer
Features
ƒ
Configurable
is specified for the extended temperature range of -40°C to
10
outputs
LVCMOS
clock
85°C.
distribution buffer
The ASM2I99446 is a full static fanout buffer design
Compatible to single, dual and mixed 3.3V/2.5V
supporting clock frequencies up to 250MHz. The signals
Voltage supply
are generated and retimed on-chip to ensure minimal skew
ƒ
Wide range output clock frequency up to 250MHz
between the three output banks. Two independent
ƒ
Designed for mid-range to high-performance
LVCMOS compatible clock inputs are available. This
telecom, networking and computer applications
feature supports redundant clock sources or the addition of
ƒ
Supports applications requiring clock redundancy
a test clock into the system design. Each of the three
ƒ
Max. output skew of 200pS (150pS within one
output banks can be individually supplied by 2.5V or 3.3V
bank)
supporting mixed voltage applications. The FSELx pins
ƒ
Selectable output configurations per output bank
choose between division of the input reference frequency
ƒ
Tristatable outputs
by one or two. The frequency divider can be set individually
ƒ
32 lead LQFP & TQFP Packages
ƒ
Ambient operating temperature range of
ƒ
for each of the three output banks. The ASM2I99446 can
-
-40 to 85°C
be reset and the outputs are disabled by deasserting the
MR/OE pin (logic high state). Asserting MR/OE will enable
the outputs.
Functional Description
All inputs accept LVCMOS signals while the outputs
The ASM2I99446 is a 2.5V and 3.3V compatible 1:10 clock
provide LVCMOS compatible levels with the capability to
distribution buffer designed for low-voltage mid-range to
drive terminated 50Ω transmission lines. Please consult the
high-performance telecom, networking and computing
ASM2I99456 specification for a 1:10 mixed voltage buffer
applications. Both 3.3V, 2.5V and dual supply voltages are
with LVPECL compatible inputs. For series terminated
supported for mixed-voltage applications. The ASM2I99446
transmission lines, each of the ASM2I99446 outputs can
offers 10 low-skew outputs and 2 selectable inputs for clock
drive one or two traces giving the devices an effective
redundancy. The outputs are configurable and support 1:1
fanout of 1:20. The device is packaged in a
and 1:2 output to input frequency ratios. The ASM2I99446
32-lead LQFP and TQFP Packages.
7x7mm2
Alliance Semiconductor
2575, Augustine Drive • Santa Clara, CA • Tel: 408.855.4900 • Fax: 408.855.4999 • www.alsc.com
Notice: The information in this document is subject to change without notice.
ASM2I99446
July 2005
rev 0.4
Block Diagram
VCC
25K 0
VCC
25K 1
CCLK0
CCLK1
CCLK_SEL
CLK
0
CLK-2
1
25K
QA0
QA1
QA2
QB0
0
QB1
1
QB2
QC0
FSELA
25K
FSELB
0
QC1
1
QC2
QC3
25K
FSELC
25K
MR/OE
25K
Pin Configuration
VCCC
VCCB
QB2
GND
QB1
VCCB
QB0
GND
32 – LEAD PACKAGE PINOUT -- Top View
24 23 22 21 20 19 18 17
VCCA
25
16
QC3
QA2
26
15
GND
GND
27
14
QC2
QA1
28
13
VCCC
VCCA
29
12
QC1
QA0
30
11
GND
GND
31
10
QC0
MR/OE
32
9
VCCC
1
2
3
4
5
6
7
8
CCLK_SEL
VCC
CCLK0
CCLK1
FSELA
FSELB
FSELC
GND
ASM2I99446
2.5V and 3.3V LVCMOS Clock Distribution Buffer
Notice: The information in this document is subject to change without notice.
2 of 14
ASM2I99446
July 2005
rev 0.4
Table 1: Pin Configuration
Pin Number
3,4
5,6,7
32
8,11,15,20,24,27,31
25,29
18,22
9,13,17
2
Pin
I/O
Type
CCLK0, CCLK1
Input
LVCMOS
LVCMOS clock inputs
FSELA, FSELB, FSELC
Input
LVCMOS
Input
LVCMOS
-
Supply
Output bank divide select input
Internal reset and output (high impedance)
control
Negative voltage supply (GND)
-
Supply
Positive voltage supply for output banks
MR/OE
GND
VCCA,
VCCB,
VCCC
VCC
Function
-
Supply
30,28, 26
QA0 - QA2
Output
LVCMOS
Bank A outputs
Positive voltage supply for core (VCC)
23,21,19
QB0 - QB2
Output
LVCMOS
Bank B outputs
10,12,14,16
QC0 - QC3
Output
LVCMOS
Bank C outputs
Note: VCCB is internally connected to VCC.
Table 2: Supported Single and Dual Supply Configurations
VCC1
VCCA2
VCCB3
VCCC4
GND
3.3V
3.3V
3.3V
3.3V
0V
Mixed voltage supply
3.3V
3.3V or 2.5V
3.3V
3.3V or 2.5V
0V
2.5V
2.5V
2.5V
2.5V
2.5V
0V
Supply voltage configuration
3.3V
Note: 1 VCC is the positive power supply of the device core and input circuitry. VCC voltage defines the input threshold and levels
2 VCCA is the positive power supply of the bank A outputs. VCCA voltage defines bank A output levels
3 VCCB is the positive power supply of the bank B outputs. VCCB voltage defines bank B output levels. VCCB is internally connected to
4 VCCC is the positive power supply of the bank B outputs. VCCC voltage defines bank C output levels.
VCC.
Table 3: Function Table (Controls)
Control
Default
0
1
CCLK_SEL
FSELA
FSELB
FSELC
0
0
0
0
CCLK0
fQA0:2 = fREF
FQBO:2 = fREF
FQCO:3 = fREF
CCLK1
f QA0:2 = fREF ÷2
f QBO:2 = fREF ÷2
f QCO:3 = fREF ÷2
MR/OE
0
Outputs enabled
Internal reset Outputs disabled (tristate)
Table 4: Absolute Maximum Ratings1
Symbol
Characteristics
Min
Max
Unit
VCC
Supply Voltage
-0.3
3.6
V
VIN
DC Input Voltage
-0.3
VCC+0.3
V
VOUT
DC Output Voltage
-0.3
VCC+0.3
V
IIN
DC Input Current
±20
mA
IOUT
DC Output Current
±50
mA
TS
Storage temperature
125
°C
-65
Condition
Note: 1 These are stress ratings only and are not implied for functional use. Exposure to absolute maximum ratings for prolonged periods of time may affect
device reliability.
2.5V and 3.3V LVCMOS Clock Distribution Buffer
Notice: The information in this document is subject to change without notice.
3 of 14
ASM2I99446
July 2005
rev 0.4
Table 5: General Specifications
Symbol
Characteristics
Min
Typ
Max
VCC ÷2
Unit
VTT
Output Termination Voltage
MM
ESD Protection (Machine Model)
200
V
HBM
ESD Protection (Human Body Model)
2000
V
LU
Latch–Up Immunity
200
mA
CPD
Power Dissipation Capacitance
10
pF
CIN
Input Capacitance
4.0
pF
Condition
V
Per output
Table 6: DC CHARACTERISTICS (VCC = VCCA = VCCB = VCCC = 3.3V ±5%, TA = –40°C to +85°C)
Symbol
VIH
VIL
IIN
Characteristics
Input High Voltage
Input Low Voltage
Min
2.0
-0.3
Typ
Input Current 1
Max
VCC + 0.3
0.8
200
VOH
Output High Voltage
2.4
VOL
Output Low Voltage
ZOUT
ICCQ3
Output Impedance
Maximum Quiescent Supply Current
0.55
0.30
14 - 17
2.0
Unit
V
V
Condition
LVCMOS
LVCMOS
µA
VIN=GND or VIN=VCC
V
V
V
Ω
mA
IOH=-24 mA2
3
IOL= 24mA
IOL= 12mA
All VCC Pins
Note: 1 Input pull-up / pull-down resistors influence input current.
2 The ASM2I99446 is capable of driving 50Ω transmission lines on the incident edge. Each output drives one 50Ω parallel terminated
to a termination voltage of VTT. Alternatively, the device drives up to two 50Ω series terminated transmission lines.
3 ICCQ is the DC current consumption of the device with all outputs open and the input in its default state or open.
2.5V and 3.3V LVCMOS Clock Distribution Buffer
Notice: The information in this document is subject to change without notice.
transmission line
4 of 14
ASM2I99446
July 2005
rev 0.4
Table 7: AC CHARACTERISTICS (VCC = VCCA = VCCB = VCCC = 3.3V ±5%, TA = –40°C to +85°C)1
Symbol
Characteristics
Max
Unit
Condition
2502
2
250
125
MHz
MHz
MHz
nS
FSELx=0
FSELx=1
1.03
4.45
4.2
nS
nS
nS
Output Disable Time
10
nS
Output Enable Time
Output-to-output Skew
10
nS
150
200
350
pS
pS
pS
2.25
200
53
55
nS
pS
%
%
DCREF = 50%
DCREF = 25%-75%
1.0
nS
0.55 to 2.4V
fref
Input Frequency
fMAX
Maximum Output Frequency
tP, REF
Reference Input Pulse Width
tr, tf
tPLH
tPHL
tPLZ, HZ
CCLK Input Rise/Fall Time
tPZL, LZ
tsk(O)
tsk(PP)
tSK(P)
DCQ
tr, tf
Min
÷1 output
÷2 output
CCLK0,1 to any Q
CCLK0,1 to any Q
Propagation delay
Typ
0
0
0
1.4
2.2
2.2
Within one bank
Any output Bank, Same output divider
Any output, Any output divider
Device-to-device Skew
Output pulse skew4
÷1 output
Output Duty Cycle
÷2 output
47
45
Output Rise/Fall Time
0.1
2.8
2.8
50
50
0.8 to 2.0V
Note: 1 AC characteristics apply for parallel output termination of 50Ω to VTT
2 The ASM2I99446 is functional up to an input and output clock frequency of 350MHz and is characterized up to 250MHz.
3 Violation of the 1.0nS maximum input rise and fall time limit will affect the device propagation delay, device-to-device skew, reference input pulse width,
output duty cycle and maximum frequency specifications.
4 Output pulse skew is the absolute difference of the propagation delay times | tpLH - tpHL |.
Table 8: DC CHARACTERISTICS (VCC = VCCA = VCCB = VCCC = 2.5V ±5%, TA = –40°C to +85°C)
Symbol
Characteristics
Min
VIH
VIL
Input High Voltage
Input Low Voltage
1.7
-0.3
VOH
Output High Voltage
1.8
VOL
Output Low Voltage
ZOUT
Output Impedance
IIN
ICCQ3
Input Current2
Maximum Quiescent Supply Current
Typ
Max
Unit
VCC + 0.3
0.7
V
V
LVCMOS
LVCMOS
V
IOH=-15 mA
V
IOL= 15 mA
0.6
17 - 202
Condition
1
Ω
±200
2.0
µA
mA
VIN=GND or VIN=VCC
All VCC Pins
Note: 1 The ASM2I99446 is capable of driving 50Ω transmission lines on the incident edge. Each output drives one 50Ω parallel terminated transmission line to
a termination voltage of VTT. Alternatively, the device drives up to two 50Ω series terminated transmission lines per output.
2 Input pull-up / pull-down resistors influence input current.
3 ICCQ is the DC current consumption of the device with all outputs open and the input in its default state or open.
2.5V and 3.3V LVCMOS Clock Distribution Buffer
Notice: The information in this document is subject to change without notice.
5 of 14
ASM2I99446
July 2005
rev 0.4
Table 9: AC CHARACTERISTICS (VCC = VCCA = VCCB = VCCC = 2.5V ±5%, TA = –40°C to +85°C)1,2
Symbol
Characteristics
fref
Input Frequency
fMAX
Maximum Output Frequency
Min
Typ
0
0
0
÷1 output
÷2 output
Max
Unit
2503
2
250
125
MHz
MHz
MHz
FSELx=0
FSELx=1
tP, REF
Reference Input Pulse Width
tr, tf
CCLK Input Rise/Fall Time
tPLH
tPHL
Propagation delay
tPLZ, HZ
Output Disable Time
10
nS
tPZL, LZ
Output Enable Time
Output-to-output Skew
10
nS
tsk(PP)
Within one bank
Any output Bank, Same output divider
Any output, Any output divider
Device-to-device Skew
150
200
350
3.0
pS
pS
pS
nS
tSK(P)
Output pulse skew5
200
pS
DCQ
Output Duty Cycle
55
%
DCREF = 50%
tr, tf
Output Rise/Fall Time
1.0
nS
0.6 to 1.8V
tsk(O)
1.4
Condition
CCLK0,1 to any Q
CCLK0,1 to any Q
nS
2.6
2.6
÷1 or ÷2 output
45
50
0.1
1.04
nS
5.6
5.5
nS
nS
0.7 to 1.7V
Note: 1 AC characteristics apply for parallel output termination of 50Ω to VTT.
2 AC specifications are design targets, final specification is pending device characterization.
3 The ASM2I99446 is functional up to an input and output clock frequency of 350MHz and is characterized up to 250MHz.
4 Violation of the 1.0nS maximum input rise and fall time limit will affect the device propagation delay, device-to-device skew, reference input pulse width,
output duty cycle and maximum frequency specifications.
5 Output pulse skew is the absolute difference of the propagation delay times: | tpLH - tpHL |.
Table 10: AC CHARACTERISTICS (VCC = 3.3V + 5%, VCCA, VCCB, VCCC = 2.5V + 5% or 3.3V + 5%, TA = –40°C to +85°C)1,2
Symbol
Characteristics
Min
Typ
Max
Unit
150
250
350
2.5
pS
pS
pS
nS
Condition
Output-to-output Skew
tsk(PP)
Within one bank
Any output Bank, Same output divider
Any output, Any output divider
Device-to-device Skew
tPLH,HL
Propagation delay
tsk(O)
CCLK0,1 to any Q
See 3.3V table
3
tSK(P)
Output pulse skew
DCQ
Output Duty Cycle
÷1 or ÷2 output
45
50
250
pS
55
%
DCREF = 50%
Note: 1 AC characteristics apply for parallel output termination of 50Ω to VTT.
2 For all other AC specifications, refer to 2.5V or 3.3V tables according to the supply voltage of the output bank.
3 Output pulse skew is the absolute difference of the propagation delay times: | tpLH - tpHL |.
2.5V and 3.3V LVCMOS Clock Distribution Buffer
Notice: The information in this document is subject to change without notice.
6 of 14
ASM2I99446
July 2005
rev 0.4
APPLICATIONS INFORMATION
impedance mismatch seen looking into the driver. The
parallel combination of the 36Ω series resistor plus the
output impedance does not match the parallel
combination of the line impedances. The voltage wave
launched down the two lines will equal:
Driving Transmission Lines
The ASM2I99446 clock driver was designed to drive high
speed signals in a terminated transmission line
environment. To provide the optimum flexibility to the
user the output drivers were designed to exhibit the
lowest impedance possible. With an output impedance of
less than 20Ω the drivers can drive either parallel or
series terminated transmission lines. In most high
performance clock networks point-to-point distribution of
signals is the method of choice. In a point-to-point
scheme either series terminated or parallel terminated
transmission lines can be used. The parallel technique
terminates the signal at the end of the line with a 50Ω
resistance to VCC÷2.
ASM2I99446
OUTPUT BUFFER
IN
14Ω
RS = 36Ω || 36Ω
R0 = 14Ω
VL = 3.0 ( 25 ÷ (18+14+25)) = 1.31V
At the load end the voltage will double, due to the near
unity reflection coefficient, to 2.5V. It will then increment
towards the quiescent 3.0V in steps separated by one
round trip delay (in this case 4.0nS).
3.0
2.5
OutA
tD = 3.8956
2.0
In
1.5
1.0
OUTA
0
2
ASM2I99446
OUTPUT BUFFER
IN
Z0=50Ω
RS=36Ω
RS=36Ω
4
6
8
10
12
14
TIME (nS)
OUTB0
14Ω
OutB
tD = 3.9386
0.5
Z0=50Ω
RS=36Ω
Z0 = 50Ω || 50Ω
VOLTAGE (V)
This technique draws a fairly high level of DC current and
thus only a single terminated line can be driven by each
output of the ASM2I99446 clock driver. For the series
terminated case however there is no DC current draw,
thus the outputs can drive multiple series terminated
lines. Figure 3. “Single versus Dual Transmission Lines”
illustrates an output driving a single series terminated line
versus two series terminated lines in parallel. When taken
to its extreme the fanout of the ASM2I99446 clock driver
is effectively doubled due to its capability to drive multiple
lines.
VL = VS ( Z0 ÷ (RS+R0 +Z0))
Z0=15Ω
OUTB1
Figure 3. Single versus Dual Transmission
Lines
The waveform plots in Figure 4. “Single versus Dual Line
Termination Waveforms” show the simulation results of
an output driving a single line versus two lines. In both
cases the drive capability of the ASM2I99446 output
buffer is more than sufficient to drive 50Ω transmission
lines on the incident edge. Note from the delay
measurements in the simulations a delta of only 43pS
exists between the two differently loaded outputs. This
suggests that the dual line driving need not be used
exclusively to maintain the tight output-to-output skew of
the ASM2I99446. The output waveform in Figure 4
“Single versus Dual Line Termination Waveforms” shows
a step in the waveform. This step is caused by the
Figure 4. Single versus Dual Waveforms
Since this step is well above the threshold region it will
not cause any false clock triggering, however designers
may be uncomfortable with unwanted reflections on the
line. To better match the impedances when driving
multiple lines the situation in Figure 5. “Optimized Dual
Line Termination” should be used. In this case the series
terminating resistors are reduced such that when the
parallel combination is added to the output buffer
impedance the line impedance is perfectly matched.
ASM2I99446
OUTPUT BUFFER
IN
RS=22Ω
14Ω
RS=22Ω
Z0=50Ω
Z0=50Ω
14Ω + 22Ω║22Ω = 50Ω║50Ω
25Ω = 25Ω
Figure 5. Optimized Dual Line Termination
2.5V and 3.3V LVCMOS Clock Distribution Buffer
Notice: The information in this document is subject to change without notice.
7 of 14
ASM2I99446
July 2005
rev 0.4
ASM2I99446
Z0=50Ω
Pulse
Generator
Z=50Ω
Z0=50Ω
RT=50Ω
RT=50Ω
VTT
Figure 6. CCLK0, 1 ASM2I99446 AC test reference for VCC = 3.3V and VCC = 2.5V
VCC
CCLK
VCC ÷2
GND
VCC = 3.3V VCC = 2.5V
2.4
1.8V
0.55
0.6V
VCC
QX
t(LH)
tR
tF
VCC ÷2
Figure 7. Output Transition Time Test Reference
GND
t(HL)
Figure 8. Propagation Delay (tPD) Test Reference
VCC
VCC
CCLK
VCC ÷2
GND
VCC ÷2
GND
VCC
VOH
VCC ÷2
tSK(LH)
tSK(HL)
QX
VCC ÷2
t(LH)
GND
t(HL)
GND
tSK(P) │tPLH- tPHL │
The pin-to-pin skew is defined as the worst case
difference in propagation delay between any similar
delay path within a single device
Figure 10. Propagation Delay (tSK(P)) Test Reference
Figure 9. Output–to–Output Skew tSK(LH,HL)
VCC
VCC ÷2
GND
TJIT(CC) = |TN -TN + 1|
TN
tP
TN + 1
The variation in cycle time of a signal between adjacent
cycles, over a random sample of adjacent cycle pairs
T0
DC (tP ÷T0 Χ 100%)
Figure 12. Cycle–to–Cycle Jitter
The time from the PLL controlled edge to the
non-controlled edge, divided by the time
between PLL controlled edges, expressed as a
percentage.
Figure 11. Output Duty Cycle (DC) Reference
2.5V and 3.3V LVCMOS Clock Distribution Buffer
Notice: The information in this document is subject to change without notice.
8 of 14
ASM2I99446
July 2005
rev 0.4
Power Consumption of the ASM2I99446 and
Thermal Management
The ASM2I99446 AC specification is guaranteed for the
entire operating frequency range up to 250MHz. The
ASM2I99446 power consumption and the associated
long-term reliability may decrease the maximum
frequency limit, depending on operating conditions such
as clock frequency, supply voltage, output loading,
ambient temperature, vertical convection and thermal
conductivity of package and board. This section
describes the impact of these parameters on the junction
temperature and gives a guideline to estimate the
ASM2I99446 die junction temperature and the associated
device reliability.
Table 11. Die junction temperature and MTBF
Junction temperature (°C)
MTBF (Years)
100
20.4
110
9.1
120
4.2
130
2.0
Increased power consumption will increase the die
junction temperature and impact the device reliability
(MTBF). According to the system-defined tolerable
MTBF, the die junction temperature of the ASM2I99446
needs to be controlled and the thermal impedance of the
board/package should be optimized. The power
dissipated in the ASM2I99446
is represented in
equation 1.
Where ICCQ is the static current consumption of the
ASM2I99446, CPD is the power dissipation capacitance
per output, (Μ)ΣCL represents the external capacitive
output load, N is the number of active outputs (N is
always 12 in case of the ASM2I99446). The ASM2I99446
supports driving transmission lines to maintain high signal
integrity and tight timing parameters. Any transmission
line will hide the lumped capacitive load at the end of the
board trace, therefore, ΣCL is zero for controlled
transmission line systems and can be eliminated from
equation 1. Using parallel termination output termination
results in equation 2 for power dissipation.
In equation 2, P stands for the number of outputs with a
parallel or thevenin termination, VOL, IOL, VOH and IOH are
a function of the output termination technique and DCQ is
the clock signal duty cycle. If transmission lines are used
ΣCL is zero in equation 2 and can be eliminated. In
general, the use of controlled transmission line
techniques eliminates the impact of the lumped capacitive
loads at the end lines and greatly reduces the power
dissipation of the device. Equation 3 describes the die
junction temperature TJ as a function of the power
consumption.
Where Rthja is the thermal impedance of the package
(junction to ambient) and TA is the ambient temperature.
According to Table 11, the junction temperature can be
used to estimate the long-term device reliability. Further,
combining equation 1 and equation 2 results in a
maximum operating frequency for the ASM2I99446 in a
series terminated transmission line system, equation 4.
2.5V and 3.3V LVCMOS Clock Distribution Buffer
Notice: The information in this document is subject to change without notice.
9 of 14
ASM2I99446
July 2005
rev 0.4
TJ,MAX should be selected according to the MTBF
system requirements and Table 11. Rthja can be derived
from Table 12. The Rthja represent data based on 1S2P
boards, using 2S2P boards will result in a lower thermal
impedance than indicated below.
Table 12. Thermal package impedance of the
32LQFP
Convection,
LFPM
Still air
100 lfpm
200 lfpm
300 lfpm
400 lfpm
500 lfpm
Rthja (1P2S
board), °C/W
86
76
71
68
66
60
Rthja (2P2S
board), °C/W
61
56
54
53
52
49
If the calculated maximum frequency is below 350 MHz, it
becomes the upper clock speed limit for the given
application conditions. The following eight derating charts
describe the safe frequency operation range for the
ASM2I99446. The charts were calculated for a maximum
tolerable die junction temperature of 110°C (120°C),
corresponding to an estimated MTBF of 9.1 years
(4 years), a supply voltage of 3.3V and series terminated
transmission line or capacitive loading. Depending on a
given set of these operating conditions and the available
device convection a decision on the maximum operating
frequency can be made.
2.5V and 3.3V LVCMOS Clock Distribution Buffer
14
Notice: The information in this document is subject to change without notice.
10 of
ASM2I99446
July 2005
rev 0.4
Package Information
32-lead TQFP Package
SECTION A-A
Dimensions
Symbol
Inches
Min
Max
Millimeters
Min
Max
A
….
0.0472
…
1.2
A1
0.0020
0.0059
0.05
0.15
A2
0.0374
0.0413
0.95
1.05
D
0.3465
0.3622
8.8
9.2
D1
0.2717
0.2795
6.9
7.1
E
0.3465
0.3622
8.8
9.2
E1
0.2717
0.2795
6.9
7.1
L
0.0177
0.0295
0.45
0.75
L1
0.03937 REF
1.00 REF
T
0.0035
0.0079
0.09
0.2
T1
0.0038
0.0062
0.097
0.157
b
0.0118
0.0177
0.30
0.45
b1
0.0118
0.0157
0.30
0.40
R0
0.0031
0.0079
0.08
0.2
a
0°
7°
0°
7°
e
0.031 BASE
0.8 BASE
2.5V and 3.3V LVCMOS Clock Distribution Buffer
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32-lead LQFP Package
SECTION A-A
Dimensions
Symbol
Inches
Min
Max
Millimeters
Min
Max
A
….
0.0630
…
1.6
A1
0.0020
0.0059
0.05
0.15
A2
0.0531
0.0571
1.35
1.45
D
0.3465
0.3622
8.8
9.2
D1
0.2717
0.2795
6.9
7.1
E
0.3465
0.3622
8.8
9.2
E1
0.2717
0.2795
6.9
7.1
L
0.0177
0.0295
0.45
0.75
L1
0.03937 REF
1.00 REF
T
0.0035
0.0079
0.09
0.2
T1
0.0038
0.0062
0.097
0.157
b
0.0118
0.0177
0.30
0.45
b1
0.0118
0.0157
0.30
0.40
R0
0.0031
0.0079
0.08
0.20
e
a
0.031 BASE
0°
7°
0.8 BASE
0°
7°
2.5V and 3.3V LVCMOS Clock Distribution Buffer
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Ordering Information
Part Number
Marking
Package Type
Operating Range
ASM2I99446-32-LT
ASM2I99446L
32-pin LQFP, Tray
Industrial
ASM2I99446-32-LR
ASM2I99446L
32-pin LQFP,Tape and Reel
Industrial
ASM2I99446G-32-LT
ASM2I99446GL
32-pin LQFP, Tray, Green
Industrial
ASM2I99446G-32-LR
ASM2I99446GL
32-pin LQFP, Tape and Reel, Green
Industrial
ASM2I99446-32-ET
ASM2I99446E
32-pin TQFP, Tray
Industrial
ASM2I99446-32-ER
ASM2I99446E
32-pin TQFP,Tape and Reel
Industrial
ASM2I99446G-32-ET
ASM2I99446GE
32-pin TQFP, Tray, Green
Industrial
ASM2I99446G-32-ER
ASM2I99446GE
32-pin TQFP,Tape and Reel, Green
Industrial
Device Ordering Information
A S M 2 I 9 9 4 4 6 G - 3 2 - L R
R = Tape & reel, T = Tube or Tray
O = SOT
S = SOIC
T = TSSOP
A = SSOP
V = TVSOP
B = BGA
Q = QFN
U = MSOP
E = TQFP
L = LQFP
U = MSOP
P = PDIP
D = QSOP
X = SC-70
DEVICE PIN COUNT
F = LEAD FREE AND RoHS COMPLIANT PART
G = GREEN PACKAGE
PART NUMBER
X= Automotive
I= Industrial
P or n/c = Commercial
(-40C to +125C) (-40C to +85C)
(0C to +70C)
1 = Reserved
2 = Non PLL based
3 = EMI Reduction
4 = DDR support products
5 = STD Zero Delay Buffer
6 = Power Management
7 = Power Management
8 = Power Management
9 = Hi Performance
0 = Reserved
ALLIANCE SEMICONDUCTOR MIXED SIGNAL PRODUCT
Licensed under US patent #5,488,627, #6,646,463 and #5,631,920.
2.5V and 3.3V LVCMOS Clock Distribution Buffer
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Alliance Semiconductor Corporation
2575, Augustine Drive,
Santa Clara, CA 95054
Tel# 408-855-4900
Fax: 408-855-4999
www.alsc.com
Copyright © Alliance Semiconductor
All Rights Reserved
Part Number: ASM2I99446
Document Version: 0.4
Note: This product utilizes US Patent # 6,646,463 Impedance Emulator Patent issued to Alliance Semiconductor, dated 11-11-2003
© Copyright 2003 Alliance Semiconductor Corporation. All rights reserved. Our three-point logo, our name and Intelliwatt are
trademarks or registered trademarks of Alliance. All other brand and product names may be the trademarks of their
respective companies. Alliance reserves the right to make changes to this document and its products at any time without
notice. Alliance assumes no responsibility for any errors that may appear in this document. The data contained herein
represents Alliance's best data and/or estimates at the time of issuance. Alliance reserves the right to change or correct this
data at any time, without notice. If the product described herein is under development, significant changes to these
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potential customers and users, and is not intended to operate as, or provide, any guarantee or warrantee to any user or
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assumes all risk of such use and agrees to indemnify Alliance against all claims arising from such use.
2.5V and 3.3V LVCMOS Clock Distribution Buffer
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