PULSECORE PCS5I961P

PCS5I961P
November 2006
rev 0.3
Low Voltage Zero Delay Buffer
Features
reference clock while the PCS5I961P offers an LVPECL
reference clock.
•
Fully Integrated PLL
•
Up to 200MHz I/O Frequency
When pulled high the OE pin will force all of the outputs
•
LVCMOS Outputs
(except QFB) into a high impedance state. Because the OE
•
Outputs Disable in High Impedance
•
LVPECL Reference Clock Options
•
LQFP Packaging
•
±50pS Cycle–Cycle Jitter
•
150pS Output Skews
pin does not affect the QFB output, down stream clocks
can be disabled without the internal PLL losing lock.
The PCS5I961P is fully 2.5V or 3.3V compatible and
requires no external loop filter components. All control
inputs accept LVCMOS compatible levels and the outputs
provide low impedance LVCMOS outputs capable of
driving terminated 50Ω transmission lines. For series
Functional Description
terminated lines the PCS5I961P can drive two lines per
The PCS5I961P is a 2.5V or 3.3V compatible, 1:18 PLL
output giving the device an effective fanout of 1:36. The
based zero delay buffer. With output frequencies of up to
device is packaged in a 32 lead LQFP package to provide
200MHz, output skews of 150pS the device meets the
the
needs of the most demanding clock tree applications.
optimum
combination
of
board
density
performance.
The PCS5I961P is offered with two different input
configurations.
The
PCS5I961P
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. PCS5I961P Logic Diagram
PulseCore Semiconductor Corporation
1715 S. Bascom Ave Suite 200, Campbell, CA 95008 • Tel: 408-879-9077 • Fax: 408-879-9018
www.pulsecoresemi.com
Notice: The information in this document is subject to change without notice.
and
PCS5I961P
November 2006
rev 0.3
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
PCS5I961C
PCS5I961P
Q16
VCC
32
9
QFB
1
2
3
4
5
6
7
8
VCC
10
FB_IN
31
OE
Q0
VCCA
Q15
F_RANGE
GND
11
PCLK
12
30
PCLK
29
Q1
GND
Q2
Figure 2. PCS5I961P 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 PCS5I961P 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
PCS5I961P
November 2006
rev 0.3
Table 2: Function Table
Control
Default
0
1
F_RANGE
0
PLL high frequency range. PCS5I961P input
reference and output clock frequency range is
100 – 200 MHz
PLL low frequency range. PCS5I961P 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
DC Output Voltage
-0.3
VOUT
VCC + 0.3
V
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)
IIN
-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
VPP
VCMR
ZOUT
2.4
0.55
Output Impedance
14
IIN
Input Current
CIN
Input Capacitance
4.0
20
Ω
±120
mA
pF
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
VCC÷2
Notes:
1. Exceeding the specified VCMR/VPP window results in a tPD changes of approx. 250pS.
2. The PCS5I961P 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
PCS5I961P
November 2006
rev 0.3
Table 5: AC Characteristics (VCC = 3.3V ± 5%, TA = -40°C to +85°C)1
Symbol
Characteristic
Min
fref
Input Frequency
F_RANGE = 0
F_RANGE = 1
fmax
Maximum Output
Frequency
F_RANGE = 0
F_RANGE = 1
frefDC
Reference Input Duty Cycle
Max
Unit
100
50
Typ
200
100
MHz
100
50
200
100
MHz
25
75
%
-50
225
pS
90
150
pS
50
50
55
55
%
1.0
nS
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
42
45
tr, tf
Output Rise/Fall Time
0.1
tPLZ,HZ
Output Disable Time
10
nS
tPZL,LZ
Output Enable Time
10
nS
4
tJIT(CC)
Cycle to Cycle Jitter
RMS (1σ)
tJIT(PER)
Period Jitter
RMS (1σ)
RMS (1σ)
F_RANGE = 0
F_RANGE = 1
tJIT(φ)
I/O Phase Jitter
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
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
V
IOL = 15mA2
VPP
VCMR
ZOUT
IIN
Characteristic
Min
Typ
1.2
1.8
0.6
Output Impedance
18
Input Current
26
Ω
±120
mA
Condition
CIN
Input Capacitance
4.0
CPD
Power Dissipation Capacitance
8.0
10
pF
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
VCC÷2
Per Output
Notes:
1. Exceeding the specified VCMR/VPP window results in a tPD changes of < 250 pS.
2. The PCS5I961P 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
PCS5I961P
November 2006
rev 0.3
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
10
nS
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
0.1
tPZL,LZ
Output Enable Time
tJIT(CC)
Cycle–to–Cycle Jitter
RMS (1σ)4
tJIT(PER)
Period Jitter
RMS (1σ)
RMS (1σ)
F_RANGE = 0
F_RANGE = 1
tJIT(φ)
I/O Phase Jitter
tlock
Maximum PLL Lock Time
40
45
7.0
10
nS
15
pS
10
pS
0.0015 ⋅ T
0.0010 ⋅ T
10
nS
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
PCS5I961P
November 2006
rev 0.3
APPLICATIONS INFORMATION
Power Supply Filtering
The PCS5I961P 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 PCS5I961P 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 PCS5I961P.
Figure 3. illustrates a typical power supply filter scheme.
The PCS5I961P 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 PCS5I961P. 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
RF = 270Ω for VCC = 3.3V
RF = 5-15Ω for VCC = 2.5V
RF
22 µF
Although the PCS5I961P 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.
Driving Transmission Lines
The PCS5I961P 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 PCS5I961P 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 PCS5I961P clock driver is effectively
doubled due to its capability to drive multiple lines.
PCS5I961P
OUTPUT BUFFER
IN
14Ω
RS=36Ω
PCS5I961P
OUTPUT BUFFER
IN
RS=36Ω
14Ω
RS=36Ω
VCCA
Z0=50Ω
OUTA
Z0=50Ω
OUTB0
Z0=50Ω
OUTB1
10 nF
PCS5I961P
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 PCS5I961P 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
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
6 of 14
PCS5I961P
November 2006
rev 0.3
the PCS5I961P. The output waveform in Figure 5. shows
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
OutA
tD = 3.8956
Using the PCS5I961P in zero-delay applications
Nested clock trees are typical applications for the
PCS5I961P. Designs using the PCS5I961P, 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 PCS5I961P 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
OutB
tD = 3.9386
The PCS5I961P 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 PCS5I961P 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
TIME (nS)
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.
PCS5I961P
OUTPUT BUFFER
IN
RS=22Ω
tPD,LINE (FB)
-t(Ø)
QFBDevice 1
tJIT(Ø)
Any QDevice 1
+tSK(O)
+t(Ø
Z0=50Ω
QFBDevice 2
tJIT(Ø)
14Ω
RS=22Ω
Z0=50Ω
Any QDevice 2
14Ω + 22Ω || 22Ω = 50Ω || 50Ω
25Ω = 25Ω
Figure 6. Optimized Dual Line Termination
+tSK(O)
Max. skew
tSK(PP)
Figure 7. PCS5I961P max. device-to-device skew
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
7 of 14
PCS5I961P
November 2006
rev 0.3
± 1σ
Probability of clock edge within the
distribution
0.68268948
± 2σ
0.95449988
± 3σ
0.99730007
The PCS5I961P AC specification is guaranteed for the
entire operating frequency range up to 200 MHz. The
PCS5I961P 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 PCS5I961P die junction
temperature and the associated device reliability.
± 4σ
0.99993663
Table 9: Die junction temperature and MTBF
± 5σ
0.99999943
Junction temperature (°C)
± 6σ
0.99999999
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.
Table 8: Confidence Factor CF
CF
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):
tSK(PP) = [–50ps...175ps] + [–150ps...150ps] +
[(12ps* –3)...(12ps *3)] + tPD, LINE(FB)
tSK(PP) = [–236ps...361ps] + tPD, LINE(FB)
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.
tjit(Ø)[ps] RMS
F_RANGE=0
F_RANGE=1
18
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
MTBF (Years)
100
20.4
110
9.1
120
130
4.2
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 PCS5I961P
needs to be controlled and the thermal impedance of the
board/package should be optimized. The power
dissipated in the PCS5I961P is represented in equation
1. Where ICCQ is the static current consumption of the
PCS5I961P, 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 PCS5I961P). The PCS5I961P
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.
Power Consumption of the PCS5I961P and Thermal
Management
Low Voltage Zero Delay Buffer
Notice: The information in this document is subject to change without notice.
8 of 14
PCS5I961P
November 2006
rev 0.3



PTOT =  I CCQ + VCC ⋅ f CLOCK ⋅  N ⋅ C PD + ∑ C L  ⋅ VCC
Equation 1
M






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 PCS5I961P 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 PCS5I961P. 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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PCS5I961P
November 2006
rev 0.3
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 PCS5I961P 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 PCS5I961P 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 PCS5I961P 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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PCS5I961P
November 2006
rev 0.3
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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PCS5I961P
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rev 0.3
Package Information
32-lead LQFP
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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PCS5I961P
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rev 0.3
Ordering Information
Marking
Part Number
Package Type
Temperature
PCS5I961PG-32LR
PCS5I961PG
32 pin LQFP, Green
Industrial
PCS5I961PG-32LR
PCS5I961PG
32 pin LQFP – Tape and Reel, Green
Industrial
Device Ordering Information
P C S
5 I 9 6 1 P
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
G = GREEN PACKAGE, LEAD FREE, and RoHS
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
PulseCore 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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PCS5I961P
November 2006
rev 0.3
PulseCore Semiconductor Corporation
1715 S. Bascom Ave Suite 200
Campbell, CA 95008
Tel: 408-879-9077
Fax: 408-879-9018
www.pulsecoresemi.com
Copyright © PulseCore Semiconductor
All Rights Reserved
Preliminary Information
Part Number: PCS5I961P
Document Version: 0.3
Note: This product utilizes US Patent # 6,646,463 Impedance Emulator Patent issued to PulseCore Semiconductor, dated 11-11-2003
© Copyright 2006 PulseCore Semiconductor Corporation. All rights reserved. Our logo and name are trademarks or
registered trademarks of PulseCore Semiconductor. All other brand and product names may be the trademarks of their
respective companies. PulseCore reserves the right to make changes to this document and its products at any time without
notice. PulseCore assumes no responsibility for any errors that may appear in this document. The data contained herein
represents PulseCore’s best data and/or estimates at the time of issuance. PulseCore 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. PulseCore does not assume any responsibility or liability arising out of the application or use of any product
described herein, and disclaims any express or implied warranties related to the sale and/or use of PulseCore products
including liability or warranties related to fitness for a particular purpose, merchantability, or infringement of any intellectual
property rights, except as express agreed to in PulseCore’s Terms and Conditions of Sale (which are available from
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The purchase of products from PulseCore does not convey a license under any patent rights, copyrights; mask works rights,
trademarks, or any other intellectual property rights of PulseCore or third parties. PulseCore does not authorize its products
for use as critical components in life-supporting systems where a malfunction or failure may reasonably be expected to result
in significant injury to the user, and the inclusion of PulseCore products in such life-supporting systems implies that the
manufacturer assumes all risk of such use and agrees to indemnify PulseCore 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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