ALSC ASM5I961PG-32LR

ASM5I961P
July 2005
rev 0.2
Low Voltage Zero Delay Buffer
Features
reference clock while the ASM5I961P offers an LVPECL
ƒ
Fully Integrated PLL
reference clock.
ƒ
Up to 200MHz I/O Frequency
When pulled high the OE pin will force all of the outputs
ƒ
LVCMOS Outputs
(except QFB) into a high impedance state. Because the OE
ƒ
Outputs Disable in High Impedance
pin does not affect the QFB output, down stream clocks
ƒ
LVPECL Reference Clock Options
ƒ
LQFP Packaging
The ASM5I961P is fully 2.5V or 3.3V compatible and
ƒ
±50pS Cycle–Cycle Jitter
requires no external loop filter components. All control
ƒ
150pS Output Skews
can be disabled without the internal PLL losing lock.
inputs accept LVCMOS compatible levels and the outputs
provide low impedance LVCMOS outputs capable of
Functional Description
driving terminated 50Ω transmission lines. For series
The ASM5I961P is a 2.5V or 3.3V compatible, 1:18 PLL
terminated lines the ASM5I961P can drive two lines per
based zero delay buffer. With output frequencies of up to
output giving the device an effective fanout of 1:36. The
200MHz, output skews of 150pS the device meets the
device is packaged in a 32 lead LQFP package to provide
needs of the most demanding clock tree applications.
the
The ASM5I961P
combination
of
board
density
performance.
The ASM5I961P is offered with two different input
configurations.
optimum
offers an LVCMOS
Block Diagram
VCC
PCLK
PCLK
Q0
50K
Ref
50K 50K
FB
FB_IN
Q1
PLL
100-200 MHz
0
50-100 MHz
1
Q2
Q3
50K
Q14
F_RANGE
50K
Q15
Q16
OE
50K
QFB
Figure 1. ASM5I961P Logic Diagram
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.
and
ASM5I961P
July 2005
rev 0.2
Q11
Q10
Q9
GND
Q8
Q7
Q6
VCC
Pin Configuration
24 23 22 21 20 19 18 17
Q5
25
16
VCC
Q4
26
15
Q12
14
Q13
13
Q14
Q3
27
GND
28
Q2
29
12
GND
Q1
30
11
Q15
Q0
31
10
Q16
VCC
32
9
QFB
4
5
PCLK
PCLK
F_RANGE
VCCA
6
7
8
VCC
3
FB_IN
2
OE
1
GND
ASM5I961P
ASM5I961C
Figure 2. ASM5I961P 32-Lead Package Pinout (Top View)
Table 1: Pin Configuration
Pin #
I/O
Type
PCLK, ¯¯¯¯¯
PCLK
Input
LVCMOS
PLL reference clock signal
7
FB_IN
Input
LVCMOS
PLL feedback signal input, connect to a QFB
output
4
F_RANGE
Input
LVCMOS
PLL frequency range select
6
¯¯
OE
Input
LVCMOS
Output enable/disable
Q0 - Q16
Output
LVCMOS
Clock outputs
9
QFB
Output
LVCMOS
PLL feedback signal output, connect to a
FB_IN
1,12,20,28
GND
Supply
Power
Negative power supply
2,3
31,30,29,27,26,25,23,22,21
,19,18,17,15,14,13,11,10
5
8,16,24,32
Pin Name
Function
VCCA
Supply
Power
PLL positive power supply (analog power
supply). The ASM5I961P requires an
external RC filter for the analog power
supply pin VCCA. Please see applications
section for details.
VCC
Supply
Power
Positive power supply for I/O and core
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
2 of 14
ASM5I961P
July 2005
rev 0.2
Table 2: Function Table
Control
Default
0
1
F_RANGE
0
PLL high frequency range. ASM5I961P input
reference and output clock frequency range is
100 – 200 MHz
PLL low frequency range. ASM5I961P input
reference and output clock frequency range is
50 – 100 MHz
¯¯
OE
0
Outputs enabled
Outputs disabled (high–impedance state)
Table 3: Absolute Maximum Ratings
Symbol
Parameter
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
TS
DC Output Current
Storage Temperature Range
±50
125
mA
°C
TDV
Static Discharge Voltage
(As per JEDEC STD 22- A114-B)
–40
2
KV
Note: 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.
Table 4: DC Characteristics (VCC = 3.3V ± 5%, TA = -40°C to +85°C)
Symbol
Characteristic
Min
Typ
Max
Unit
Condition
VIH
Input HIGH Voltage
2.0
VCC + 0.3
V
LVCMOS
VIL
–0.3
0.8
V
LVCMOS
500
1000
mV
LVPECL
1.2
VCC – 0.8
V
LVPECL
VOH
Input LOW Voltage
Peak–to–peak input voltage1
PECL_CLK, ¯¯¯¯¯¯¯¯¯¯
PECL_CLK
Common Mode Range1
PECL_CLK, ¯¯¯¯¯¯¯¯¯¯
PECL_CLK
Output HIGH Voltage
V
IOH = –20mA2
VOL
Output LOW Voltage
V
IOL = 20mA2
ZOUT
Output Impedance
IIN
Input Current
CIN
Input Capacitance
4.0
CPD
Power Dissipation Capacitance
8.0
10
pF
Per Output
ICCA
Maximum PLL Supply Current
2.0
5.0
mA
VCCA Pin
ICC
VTT
Maximum Quiescent Supply Current
Output Termination Voltage
mA
V
All VCC Pins
VPP
VCMR
2.4
0.55
14
20
Ω
±120
mA
pF
VCC÷2
Notes:
1. Exceeding the specified VCMR/VPP window results in a tPD changes of approx. 250pS.
2. The ASM5I961P 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 two 50Ω series terminated transmission lines.
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
3 of 14
ASM5I961P
July 2005
rev 0.2
Table 5: AC Characteristics (VCC = 3.3V ± 5%, TA = -40°C to +85°C)1
Symbol
Characteristic
Min
Typ
Max
Unit
fref
Input Frequency
F_RANGE = 0
F_RANGE = 1
100
50
200
100
MHz
fmax
Maximum Output
Frequency
F_RANGE = 0
F_RANGE = 1
100
50
200
100
MHz
25
75
%
–50
225
pS
90
150
pS
50
50
55
55
%
1.0
nS
10
nS
10
nS
frefDC
Reference Input Duty Cycle
Condition
2
t(φ)
tsk(O)
DCO
PECL_CLK to
Propagation Delay
FB_IN
(static phase offset)
3
Output to Output Skew
F_RANGE = 0
Output Duty Cycle
F_RANGE = 1
tr, tf
Output Rise/Fall Time
tPLZ,HZ
Output Disable Time
tPZL,LZ
Output Enable Time
42
45
0.1
4
tJIT(CC)
Cycle to Cycle Jitter
RMS (1σ)
tJIT(PER)
Period Jitter
tJIT(φ)
I/O Phase Jitter
RMS (1σ)
RMS (1σ)
F_RANGE = 0
F_RANGE = 1
tlock
Maximum PLL Lock Time
15
pS
10
pS
0.0015 ⋅ T
0.0010 ⋅ T
10
nS
7.0
PLL locked
0.55 to 2.4V
T = Clock
Signal
Period
mS
Notes:
1. AC characteristics apply for parallel output termination of 50Ω to VTT.
2. tPD applies for VCMR = VCC–1.3V and VPP = 800mV
3. See applications section for part to part skew calculation
4. See applications section for calculation for other confidence factors than 1σ
Table 6: DC Characteristics (VCC = 2.5V ± 5%, TA = –40° to 85°C)
Symbol
Max
Unit
Condition
VIH
Input HIGH Voltage
1.7
VCC + 0.3
V
LVCMOS
VIL
–0.3
0.7
V
LVCMOS
500
1000
mV
LVPECL
VCC – 0.7
V
LVPECL
VOH
Input LOW Voltage
Peak–to–peak input voltage1
PECL_CLK, ¯¯¯¯¯¯¯¯¯¯
PECL_CLK
Common Mode Range1
PECL_CLK, ¯¯¯¯¯¯¯¯¯¯
PECL_CLK
Output HIGH Voltage
V
IOH = –15mA2
VOL
Output LOW Voltage
0.6
V
IOL = 15mA2
ZOUT
Output Impedance
26
Ω
IIN
Input Current
±120
mA
CIN
Input Capacitance
4.0
CPD
Power Dissipation Capacitance
8.0
10
pF
ICCA
Maximum PLL Supply Current
2.0
5.0
mA
VCCA Pin
ICC
VTT
Maximum Quiescent Supply Current
Output Termination Voltage
mA
V
All VCC Pins
VPP
VCMR
Characteristic
Min
Typ
1.2
1.8
18
pF
VCC÷2
Per Output
Notes:
1. Exceeding the specified VCMR/VPP window results in a tPD changes of < 250 pS.
2. The ASM5I961P 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 two 50Ω series terminated transmission lines.
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
4 of 14
ASM5I961P
July 2005
rev 0.2
Table 7: AC Characteristics (VCC = 2.5V ± 5%, TA = -40°C to +85°C)1
Symbol
Characteristic
fref
Input Frequency
F_RANGE = 0
F_RANGE = 1
fmax
Maximum Output
Frequency
F_RANGE = 0
F_RANGE = 1
frefDC
Reference Input Duty Cycle
Min
Max
Unit
100
50
Typ
200
100
MHz
100
50
200
100
MHz
25
75
%
–50
175
pS
90
150
pS
50
50
60
55
%
1.0
nS
Condition
2
t(φ)
tsk(O)
DCO
tr, tf
PECL_CLK to
Propagation Delay
FB_IN
(static phase offset)
3
Output–to–Output Skew
F_RANGE = 0
Output Duty Cycle
F_RANGE = 1
Output Rise/Fall Time
40
45
0.1
tPLZ,HZ
Output Disable Time
10
nS
tPZL,LZ
Output Enable Time
10
nS
tJIT(CC)
Cycle–to–Cycle Jitter
RMS (1σ)4
15
pS
tJIT(PER)
Period Jitter
10
pS
tJIT(φ)
I/O Phase Jitter
RMS (1σ)
RMS (1σ)
F_RANGE = 0
F_RANGE = 1
nS
tlock
Maximum PLL Lock Time
0.0015 ⋅ T
0.0010 ⋅ T
10
7.0
PLL locked
0.6 to 1.8V
T = Clock
Signal
Period
mS
Notes:
1. AC characteristics apply for parallel output termination of 50Ω to VTT.
2. tPD applies for VCMR = VCC–1.3V and VPP = 800mV
3. See applications section for part–to–part skew calculation
4. See applications section for calculation for other confidence factors than 1σ
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
5 of 14
ASM5I961P
July 2005
rev 0.2
APPLICATIONS INFORMATION
Power Supply Filtering
The ASM5I961P is a mixed analog/digital product and as
such it exhibits some sensitivities that would not
necessarily be seen on a fully digital product. Analog
circuitry is naturally susceptible to random noise,
especially if this noise is seen on the power supply pins.
The ASM5I961P provides separate power supplies for
the output buffers (VCC) and the phase–locked loop
(VCCA) of the device. The purpose of this design
technique is to isolate the high switching noise digital
outputs from the relatively sensitive internal analog
phase–locked loop. In a controlled environment such as
an evaluation board this level of isolation is sufficient.
However, in a digital system environment where it is more
difficult to minimize noise on the power supplies a second
level of isolation may be required. The simplest form of
isolation is power supply filter on the VCCA pin for the
ASM5I961P.
Figure 3. illustrates a typical power supply filter scheme.
The ASM5I961P is most susceptible to noise with
spectral content in the 10KHz to 5MHz range. Therefore
the filter should be designed to target this range. The key
parameter that needs to be met in the final filter design is
the DC voltage drop that will be seen between the VCC
supply and the VCCA pin of the ASM5I961P. From the
data sheet the ICCA current (the current sourced through
the VCCA pin) is typically 2mA (5mA maximum), assuming
that a minimum of 2.375V (VCC =3.3V or VCC = 2.5V)
must be maintained on the VCCA pin. The resistor RF
shown in Figure 3. must have a resistance of 270
(VCC = 3.3V) or 5 to 15 (VCC = 2.5V) to meet the voltage
drop criteria. The RC filter pictured will provide a
broadband filter with approximately 100:1 attenuation for
noise whose spectral content is above 20KHz. As the
noise frequency crosses the series resonant point of an
individual capacitor it’s overall impedance begins to look
inductive and thus increases with increasing frequency.
The parallel capacitor combination shown ensures that a
low impedance path to ground exists for frequencies well
above the bandwidth of the PLL.
VCC
Driving Transmission Lines
The ASM5I961P 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 15Ω 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. 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 ASM5I961P
clock driver. For the series terminated case however
there is no DC current draw, thus the outputs can drive
multiple series terminated lines. Figure 4. illustrates an
output driving a single series terminated line vs two series
terminated lines in parallel. When taken to its extreme the
fanout of the ASM5I961P clock driver is effectively
doubled due to its capability to drive multiple lines.
ASM5I961P
OUTPUT BUFFER
IN
14Ω
RS=36Ω
ASM5I961P
OUTPUT BUFFER
IN
RF = 270Ω for VCC = 3.3V
RF = 5-15Ω for VCC = 2.5V
RF
22 µF
Although the ASM5I961P has several design features to
minimize the susceptibility to power supply noise (isolated
power and grounds and fully differential PLL) there still
may be applications in which overall performance is being
degraded due to system power supply noise. The power
supply filter schemes discussed in this section should be
adequate to eliminate power supply noise related
problems in most designs.
RS=36Ω
14Ω
RS=36Ω
Z0=50Ω
OUTA
Z0=50Ω
OUTB0
Z0=50Ω
OUTB1
VCCA
10 nF
ASM5I961P
VCC
33…100 nF
Figure 3. Power Supply Filter
Figure 4. Single versus Dual Transmission Lines
The waveform plots of Figure 5. show the simulation
results of an output driving a single line vs two lines. In
both cases the drive capability of the ASM5I961P 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 ASM5I961P. The output waveform in Figure 5. shows
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
6 of 14
ASM5I961P
July 2005
rev 0.2
a step in the waveform, this step is caused by the
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:
VL = VS ( Zo / (Rs + Ro +Zo))
Zo = 50Ω || 50Ω
Rs = 36Ω || 36Ω
Ro = 14Ω
VL = 3.0 (25 / (18 + 14 + 25) = 3.0 (25 / 57)
= 1.31V
At the load end the voltage will double, due to the near
unity reflection coefficient, to 2.62V. It will then increment
towards the quiescent 3.0V in steps separated by one
round trip delay (in this case 4.0nS).
3.0
VOLTAGE (V)
2.5
Nested clock trees are typical applications for the
ASM5I961P. Designs using the ASM5I961P, as LVCMOS
PLL fanout buffer with zero insertion delay will show
significantly lower clock skew than clock distributions
developed from CMOS fanout buffers. The external
feedback option of the ASM5I961P clock driver allows for
its use as a zero delay buffer. By using the QFB output as
a feedback to the PLL the propagation delay through the
device is virtually eliminated. The PLL aligns the
feedback clock output edge with the clock input reference
edge resulting a near zero delay through the device. The
maximum insertion delay of the device in zero-delay
applications is measured between the reference clock
input and any output. This effective delay consists of the
static phase offset, I/O jitter (phase or long-term jitter),
feedback path delay and the output-to-output skew error
relative to the feedback output.
Calculation of part-to-part skew
OutA
tD = 3.8956
OutB
tD = 3.9386
The ASM5I961P zero delay buffer supports applications
where critical clock signal timing can be maintained
across several devices. If the reference clock inputs of
two or more ASM5I961P are connected together, the
maximum overall timing uncertainty from the common
PCLK input to any output is:
2.0
In
1.5
1.0
tSK(PP) = t(φ) + tSK(O) + tPD, LINE(FB) + tJIT(φ) ⋅ CF
0.5
This maximum timing uncertainty consist of 4
components: static phase offset, output skew, feedback
board trace delay and I/O (phase) jitter:
0
2
4
6
8
10
12
14
PCLKCommon
Figure 5. 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 6. 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.
ASM5I961P
OUTPUT BUFFER
RS=22Ω
Z0=50Ω
tPD,LINE (FB)
-t(Ø)
TIME (nS)
QFBDevice 1
tJIT(Ø)
Any QDevice 1
+tSK(O)
+t(Ø
QFBDevice 2
tJIT(Ø)
IN
14Ω
RS=22Ω
Z0=50Ω
Any QDevice 2
14Ω + 22Ω || 22Ω = 50Ω || 50Ω
25Ω = 25Ω
Figure 6. Optimized Dual Line Termination
Using the ASM5I961P in zero-delay applications
+tSK(O)
Max. skew
tSK(PP)
Figure 7. ASM5I961P max. device-to-device skew
Due to the statistical nature of I/O jitter a rms value (1σ) is
specified. I/O jitter numbers for other confidence factors
(CF) can be derived from Table 8.
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
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ASM5I961P
July 2005
rev 0.2
Table 8: Confidence Factor CF
± 1σ
Probability of clock edge within the
distribution
0.68268948
± 2σ
0.95449988
± 3σ
0.99730007
± 4σ
0.99993663
± 5σ
0.99999943
± 6σ
0.99999999
CF
Table 9: Die junction temperature and MTBF
The feedback trace delay is determined by the board
layout and can be used to fine-tune the effective delay
through each device. In the following example calculation
a I/O jitter confidence factor of 99.7% (± 3 σ) is assumed,
resulting in a worst case timing uncertainty from input to
any output of -236pS to 361pS relative to PCLK (f=125
MHz, VCC=2.5V):
Junction temperature (°C)
tSK(PP) = [–50ps...175ps] + [–150ps...150ps] +
[(12ps* –3)...(12ps *3)] + tPD, LINE(FB)
tSK(PP) = [–236ps...361ps] + tPD, LINE(FB)
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 ASM5I961P
needs to be controlled and the thermal impedance of the
board/package should be optimized. The power
dissipated in the ASM5I961P is represented in equation
1. Where ICCQ is the static current consumption of the
ASM5I961P, CPD is the power dissipation capacitance
per output, (M)ΣCL represents the external capacitive
output load, N is the number of active outputs (N is
always 27 in case of the ASM5I961P). The ASM5I961P
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.
Due to the frequency dependence of the I/O jitter, Figure
8. “Max. I/O Jitter versus frequency” can be used for a
more precise timing performance analysis.
F_RANGE=0
F_RANGE=1
18
tjit(Ø)[ps] RMS
The ASM5I961P AC specification is guaranteed for the
entire operating frequency range up to 200 MHz. The
ASM5I961P power consumption and the associated longterm 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 ASM5I961P die junction
temperature and the associated device reliability.
TA = 85°C
16
14
VCC=2.5V
12
VCC=3.3V
10
VCC=3.3V
8
VCC=2.5V
6
4
2
0
50
70
90
110
130
170
190
150
Clock frequency [MHz]
Figure 8. Max. I/O Jitter versus frequency
Power Consumption of the ASM5I961P and Thermal
Management
100
MTBF (Years)
20.4
110
9.1
120
130
4.2
2.0
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
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ASM5I961P
July 2005
rev 0.2



PTOT =  I CCQ + VCC ⋅ f CLOCK ⋅  N ⋅ C PD + ∑ C L  ⋅ VCC
M



Equation 1



PTOT = VCC ⋅  I CCQ + VCC ⋅ f CLOCK ⋅  N ⋅ C PD + ∑ C L  + ∑ DC Q ⋅ I OH (VCC − VOH ) + (1 − DC Q ) ⋅ I OL ⋅ VOL Equation 2
M

 P

TJ = T A + PTOT ⋅ Rthja
Equation 3
[
f CLOCKMAX =
C PD
1
2
⋅ N ⋅ VCC
T

− TA
⋅  JMAX
− (I CCQ ⋅ VCC )
 Rthja

Where Rthja is the thermal impedance of the package
(junction to ambient) and TA is the ambient temperature.
According to Table 9, 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 ASM5I961P in a
series terminated transmission line system.
Table 10: Thermal package impedance of the 32LQFP
Convection, LFPM
]
Rthja (1P2S board), K/W
Still air
80
100 lfpm
70
200 lfpm
61
300 lfpm
57
400 lfpm
500 lfpm
56
55
Equation 4
boards, using 2S2P boards will result in a lower thermal
impedance than indicated below. If the calculated
maximum frequency is below 200 MHz, it becomes the
upper clock speed limit for the given application
conditions. The following two derating charts describe the
safe frequency operation range for the ASM5I961P. The
charts were calculated for a maximum tolerable die
junction temperature of 110°C, corresponding to an
estimated MTBF of 9.1 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.
There are no operating frequency limitations if a 2.5V
power supply or the system specifications allow for a
MTBF of 4 years (corresponding to a max. junction
temperature of 120°C.
TJ,MAX should be selected according to the MTBF system
requirements and Table 9. Rthja can be derived from
Table 10. The Rthja represent data based on 1S2P
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
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Operating frequency (MHz)
Operating frequency (MHz)
190
TA = 85°C
160
140
120
100
80
Safe operation
60
fMAX (AC)
200
fMAX (AC)
200
190
TA = 75°C
160
TA = 85°C
140
120
100
80
Safe operation
60
40
40
20
20
0
0
500
400
200
300
Convection Ifpm
100
0
Figure 9. Maximum ASM5I961P frequency, VCC = 3.3V, MTBF
9.1 years, driving series terminated transmission lines
Differential
Pulse Generator
Z=50Ω
500
400
200
300
Convection Ifpm
100
0
Figure 10. Maximum ASM5I961P frequency, VCC = 3.3V, MTBF
9.1 years, 4pF load per line
Z0=50Ω
Z0=50Ω
RT=50Ω
RT=50Ω
VTT
VTT
Figure 11. TCLK ASM5I961P AC test reference for VCC = 3.3V and VCC = 2.5V
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
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PCLK
VPP
VCC = 3.3V
VCMR
PCLK
VCC
Ext_FB
2.4
1.8V
0.55
0.6V
tR
tF
VCC ÷2
VCC = 2.5V
GND
t(Ø)
Figure 13. Output Transition Time Test Reference
Figure 12. Propagation Delay (t(Ø)). Static phase offset
test reference
VCC
VCC ÷2
VCC
GND
VCC ÷2
GND
VCC
tP
VCC ÷2
GND
tSK(O)
T0
The pin-to-pin skew is defined as the worst case
difference in propagation delay between any similar
delay path within a single device
DC= (tP ÷T0 Χ 100%)
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 15. Output–to–Output Skew tSK(O)
Figure 14. Output Duty Cycle (DC)
T0
TN
TN-1
TJIT(CC) =│TN-TN-1 mean│
The variation in cycle time of a signal between adjacent
cycles, over a random sample of adjacent cycle pairs
TJIT(PER) =│TN-1/f0│
The deviation in cycle time of a signal with respect to the
ideal period over a random sample of cycles
Figure 16. Cycle-to-cycle Jitter
Figure 17. Period Jitter
PCLK
PCLK
Ext_FB
TJIT(Ø) =│T0-T1 mean│
The deviation in t0 for a controlled edge with respect to a t0 mean
in a random sample of cycles
Figure 18.I/O Jitter
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
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Package Information
32-lead LQFP Package
SECTION A-A
Symbol
Dimensions
Inches
Millimeters
Min
Max
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°
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
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Ordering Information
Marking
Part Number
Package Type
Temperature
ASM5I961P-32LR
ASM5I961P
32 pin LQFP
Industrial
ASM5I961P-32LR
ASM5I961P
32 pin LQFP – Tape and Reel
Industrial
ASM5I961PG-32LR
ASM5I961PG
32 pin LQFP, Green
Industrial
ASM5I961PG-32LR
ASM5I961PG
32 pin LQFP – Tape and Reel, Green
Industrial
Device Ordering Information
A S M
5 I 9 6 1 P
F - 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.
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
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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: ASM5I961P
Document Version: 0.2
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
specifications are possible. The information in this product data sheet is intended to be general descriptive information for
potential customers and users, and is not intended to operate as, or provide, any guarantee or warrantee to any user or
customer. Alliance does not assume any responsibility or liability arising out of the application or use of any product
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including liability or warranties related to fitness for a particular purpose, merchantability, or infringement of any intellectual
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assumes all risk of such use and agrees to indemnify Alliance against all claims arising from such use.
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
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