Scalable Pads for XC166 Microcontrollers

Application Note, V1.1, September 2006
AP16099
Scalable Pads
E l ec tr ica l S p eci f ica t io n o f
S c a la bl e Ou t pu t D r i vers
i n 2 50 nm C M O S Te c hn ol og y
XC166 Microcontroller Family
Microcontrollers
Never stop thinking.
AP16099
Scalable Output Drivers of XC166 Family
Edition 2006-09
Published by
Infineon Technologies AG
81726 München, Germany
© Infineon Technologies AG 2006.
All Rights Reserved.
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Scalable Output Drivers of XC166 Family
Revision History:
2006-09
Previous Version: V1.0
Page
Subjects (major changes since last revision)
11
Corrected “strong-soft” in Table 2 to “strong-sharp”
125
Corrected strong-sharp driver assessment for driving a 35pF load at 15MHz
V1.1
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Table of Contents
Page
1
Preface ............................................................................................................................ 5
2
2.1
2.1.1
2.1.2
2.2
2.2.1
2.2.2
2.2.3
Introduction ...................................................................................................................... 6
Pad driver scaling in detail ............................................................................................... 6
Driver characteristics .................................................................................................... 6
Edge Characteristics..................................................................................................... 6
Physical basics ................................................................................................................ 7
Load charging............................................................................................................... 7
Signal integrity .............................................................................................................. 8
Power integrity / Electromagnetic emission................................................................... 9
3
3.1
3.1.1
3.1.2
Measured Timings ......................................................................................................... 10
Load conditions and ambient temperatures.................................................................... 10
Measurement conditions used in this document ......................................................... 10
Measured rise and fall times ....................................................................................... 11
4
4.1
4.1.1
4.1.2
4.1.3
Simulated Timings ......................................................................................................... 28
Simulated timings on selected PCB trace structures ...................................................... 28
Description of structures ............................................................................................. 28
Rise/fall time diagrams................................................................................................ 29
Rise/fall waveforms..................................................................................................... 62
5
5.1
5.1.1
5.1.2
5.1.3
5.2
Measured Electromagnetic Emission ............................................................................. 79
Description of test equipment......................................................................................... 79
Conducted emission test configuration ....................................................................... 79
Radiated emission test configuration .......................................................................... 80
Instruments and software for emission data recognition............................................. 80
Emission measurement results ...................................................................................... 81
6
6.1
6.2
6.3
Result discussion ......................................................................................................... 109
CLKOUT driver, conducted emission ........................................................................... 109
GPIO drivers, conducted emission............................................................................... 111
Radiated emission ....................................................................................................... 120
7
7.1
7.2
Recommended settings for signal categories............................................................... 122
General........................................................................................................................ 122
Decision Tables and Graphs........................................................................................ 123
8
Glossary ...................................................................................................................... 141
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1
Preface
Output driver scaling, also referred to as „slew rate control“, is an effective technique to reduce the
electromagnetic emission of an integrated circuit by reducing the driver strength and/or smoothing
the rising and falling edges of one or more pad output drivers.
Output driver scaling makes sense only when a certain margin regarding signal frequency and/or
capacitive output load is available. Any driver scaling must maintain proper signal integrity.
This application note presents a huge set of output driver characterization data, which shall enable
the system designers to select proper driver settings to reduce the electromagnetic emission caused
by the driver switching, while maintaining the desired signal integrity. Parameters under consideration
are switching frequency, capacitive output load, and ambient temperature.
Chapter 2 introduces physical basics behind the scaling.
Chapter 3 provides a set of measured rise/fall times under various conditions.
Chapter 4 documents rise/fall time simulations performed on PCB models of different signal routing
structures.
Chapter 5 shows a set of measured electromagnetic emission under various conditions.
Chapter 6 discusses these emission results using a lot of comparison diagrams.
Chapter 7 recommends useful settings for the drivers by introducing signal categories and giving lots
of decision tables and graphs.
The application note ends with a glossary.
The data provided in chapter 7 should be preferrably referenced if a suitable pad driver setting is
searched for a given signal data rate and a given capacitive load connected to this signal. This
suitable pad driver setting leads to minimum electromagnetic emission under the given constraints for
data rate and capacitive load.
Chapters 3 to 6 serve as data pool for detailled timing and electromagnetic emission behaviour for all
pad driver settings under various temperature and capacitve load conditions.
The information given in this application note is valid for Infineon microcontrollers of the XC166
Family, fabricated in 250 nm CMOS technology.
Please note that all numbers given in this application note are no specification values. They are
verified by design without being monitored during the IC fabrication process. The numbers are based
on timing measurements performed on center lot devices. Thus all values are subject to approx. 10%
offset, depending on parameter variations such as fabrication process and pad supply voltages
different from nominal conditions. The final selection of driver settings in system applications should
consider this offset.
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2
Introduction
Output driver scaling is introduced by setting corresponding control bits in registers. Fig. 1 shows an
example of a pad driver control register, taken from the XC161 specification. While the location and
function of the control bits may differ among the available Infineon microcontrollers, the electrical
effects caused by these bits remain similar for a given technology.
2.1
Pad driver scaling in detail
2.1.1
Driver characteristics
Basically, we distinguish between driver
control and edge control. Driver control bits
set the general DC driving capability of the
respective driver. Reducing the driver
strength increases the output’s internal
resistance which attenuates noise that is
imported/exported via the output line.
For a given external load, charging and
discharging time varies with the driver
strength, thus the rise/fall times will change
accordingly. For driving LEDs or power
transistors, however, a stable high output
current may still be required independent of
low toggle rates which would normally allow
to decide for weak drivers due to their low
transitions and thus low noise emission.
The controllable output drivers of the XC161
pins feature three differently sized transistors
Figure 1: Pad output driver schematic
(strong, medium, and weak) for each
direction (push and pull). The time of activating/deactivating these transistors determines the output
characteristics of the respective port driver.
The strength of the driver can be selected to adapt the driver characteristics to the application’s
requirements:
In Strong Driver Mode, the medium and strong transistors are activated. In this mode the driver
provides maximum output current even after the target signal level is reached.
In Medium Driver Mode, only the medium transistor is activated while the other transistors remain
off.
In Weak Driver Mode, only the weak
transistor is activated while the other
transistors remain off. This results in smooth
transitions with low current peaks (and
reduced susceptibility for noise) on the cost
of increased transition times, i.e. slower
edges, depending on the capacitive load, and
low static current.
2.1.2
Edge Characteristics
This defines the rise/fall time for the
respective output, i.e. the output transition
time. Soft edges reduce the peak currents
that are drawn when changing the voltage
level of an external capacitive load. For a bus
interface, however, sharp edges may still be
required. Edge characteristic effects the predriver which controls the final output driver
stage.
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Figure 2: Port output control register example
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The Port Output Control registers POCONx provide the corresponding control bits. A 4-bit control
field configures the driver strength and the edge shape. Word ports consume four control nibbles
each, byte ports consume two control nibbles each, where each control nibble controls 4 pins of the
respective port. Fig. 2 shows an example of a POCON register and the allocation of control bit fields
and port pins.
In this guideline, the scaling effects of output drivers fabricated in 250nm CMOS technology is
described. It serves as a reference addendum to the respective microcontroller product specifications
where the individual bit settings can be found.
2.2
Physical basics
Two main constraints have to be met when deciding for a certain clock driver setting: signal integrity
and power integrity. Both issues will be discussed after a general introduction to capacitive load
charging.
2.2.1
Load charging
Generally, a switching transistor output stage delivers charge to its corresponding load capacitor
during rising edge and draws charge from its load capacitor during falling edge. Timing diagrams
normally show the signal’s voltage over time characteristics. However, the resulting timing is a result
of the electrical charge transfer described above. Charge is transferred by flowing current.
A bigger pad driver means a smaller resistance in the loading path of the external load. Fig. 3 shows
the load current and voltage of two examples of pad drivers connected to a load of C=40pF. The
strong driver has on output resistance of 25Ω, the weak driver 50Ω. For times t<0, the output voltage
is 0V. At t=0, the load capacitor C is connected to the target output voltage U=5V via the respective
driver pullup transistor. As a reaction, the load current steps immediately to the value I=U/R. I is
bigger for smaller values of R. This means that the strong driver generates a bigger current jump and
charges the load capacitor in
a shorter time.
In frequency domain, the
current
peak
which
is
resulting from the charging of
the load capacitor and from
the over- or undershoots,
causes significant RF energy
and thus electromagnetic
emission on the pad power
supply. These effects are
discussed in chapter 2.2.3.
Charging Voltage and Current at 40pF Load
0.2
4.5
0.18
4
0.16
3.5
0.14
3
0.12
2.5
0.1
2
0.08
1.5
0.06
1
0.04
0.5
0.02
0
-2.0E-09
0.0E+00
2.0E-09
4.0E-09
6.0E-09
8.0E-09
Current [A]
5
Voltage [V]
In time domain this leads to
bigger reflections for not
adapted driver impedances.
Since
typical
trace
impedances range from 60 to
120Ω , a strong driver with
Z=10Ω is poorly adapted and
may cause big voltage overand undershoots. A weak
driver with Z=100Ω may fit
perfectly and generate a
clean voltage switching signal
without over- or undershoots.
These effects are discussed
in chapter 2.2.2.
0
1.0E-08
Time [s]
Voltage R=50Ohm
Voltage R=25Ohm
Current R=50Ohm
Current R=25Ohm
Figure 3: Current-/voltage charging curves for
different driver strengths
Not only the pad driver
impedance, but also the connected capacitive load determines the electromagnetic emission
amplitudes. Fig. 4 illustrates the differences in charging current and voltage between a capacitive
load of 40pF and one of 20pF. In both cases, the driver impedance is set to 50Ω.
As expected, the charging voltage increases faster for a smaller load. However, the starting value of
the charging current is only determined by the driver impedance and is thus load-independent. The
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The selection of a weaker
driver setting slows down the
pad switching time, so care
must be taken to maintain the
required signal integrity.
5
0.2
4.5
0.18
4
0.16
3.5
0.14
3
0.12
2.5
0.1
2
0.08
1.5
0.06
1
0.04
0.5
0.02
0
-2.0E-09
0.0E+00
2.0E-09
4.0E-09
6.0E-09
8.0E-09
Current [A]
This disadvantage can be
compensated by chosing a
smaller pad driver, i.e. a
weaker driver setting, causing
bigger driver impedance and
thus smaller di/dt for the
charging current.
Charging Voltage and Current at 50Ohm Driver Impedance
Voltage [V]
load affects only the speed of
load current decrease. It
decreases faster if the load is
smaller. This means on the
other hand a bigger di/dt for
smaller loads, resulting in
higer emission for smaller
loads.
0
1.0E-08
Time [s]
Voltage Cload=40pF
Voltage Cload=20pF
Current Cload=40pF
Current Cload=20pF
Figure 4: Current-/voltage charging curves for
different capacitive loads
2.2.2
Signal integrity
Maintaining signal integrity means to select the rise/fall times such that all signal handshaking and
data communication timing and levels are ensured for proper system operation. This means the data
interchange between the microcontroller and external ICs like Flash memory, line drivers, receivers
and transmitters etc. runs properly.
Therefore, it has to be taken into account that CMOS transistors become slower with rising
temperature. Thus the timing of a critical signal has to be matched for proper operation at highest
ambient temperature. Depending
on the application, common
temperature ranges are up to
85°C or up to 125°C. Several
automotive control units specify an
ambient temperature range from 40°C up to 125°C. The die
temperature may reach values up
to 150°C during operation.
Rules:
•
Choose
driver
characteristics to meet the
DC driving requirements.
Make sure that the DC
current provided by the
microcontroller’s
pad
drivers is sufficient to drive
actuators into the desired
logic state.
•
Choose edge settings to
Figure 5: Signal over- and undershoots
meet
system
timing
constraints at the highest
system temperature. Make sure that no too strong driver settings are selected. This would
lead to unnecessarily fast signal edges, causing two disadvantages regarding
electromagnetic emission: (1) The slopes are too fast and cause undesired high emission
energy at higher frequencies; (2) Over- and undershoot appears with the danger of latchup,
spikes leading to wrong logic states or increased data stable delays and undesired high
frequency emission.
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•
2.2.3
If system timing requires short signal rise/fall times, series termination is recommended to
avoid over-/undershoot at signal transitions, see Fig. 5. The value of the termination resistor
has to be chosen identical to the signal line impedance.
Power integrity / Electromagnetic emission
Any switching between low and high voltage levels generates RF noise. This happens whenever the
switching voltage or the switching current has no sinusoidal shape. Switching currents are mainly
responsible for electromagnetic emission because of the voltage drop across line inductances such
as bond wires and lead
frames. Any shapes
other than sinusoidal
are composed by the
overlay
of
multiple
frequencies,
also
known as harmonics.
To reach a significantly
steep edge of
a
trapezoidal voltage of a
clock
signal,
short
current pulses during
the edges are required.
These
switching
currents are outlined as
nearly triangular peaks
which are composed
from
the
base
frequency and a set of
odd
and
even
harmonics, depending
Figure 6: Spectrum envelope for different clocks and edges
on the exact pulse
shape.
The steeper a switching pulse is, the higher frequencies are required to form the rising and falling
edges. A rise time of 1ns leads to a spectrum composed from harmonics up to at least 500 MHz.
A typical clock signal consists of 10% rise time, 40% high level, 10% fall time and 40% low level.
Operating at 100MHz – equal to 10ns period time – this clock signal already generates at least
harmonics up to 500MHz.
Unfortunately not the clock frequency, but the rise/fall times determine the resulting RF spectrum.
Even if a clock driver operates at a relatively low toggle rate, it may generate the same RF spectrum
as if it would operate at a significantly higher toggle rate – as long as its rise/fall times are not
adjusted to the lower toggle rate by slowing down the transitions. For example, if the mentioned
100MHz clock driver operates at only 10 MHz, its rise/fall times should be extended from 1 ns to 10
ns, still maintaining the 10% ratio relatively to the clock period time. Fig. 6 illustrates that behaviour.
Rule:
•
Choose driver and edge characteristics to result in lowest electromagnetic emission while
meeting all system timing requirements at highest system temperature.
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Measured Timings
3.1
Load conditions and ambient temperatures
The XC16x microcontroller family uses two types of pad drivers: CLKOUT serving as a timing
reference signal provides stronger drivers than all other port pins. These other port pins are referred
to as “General Purpose I/Os” (GPIO).
3.1.1
Measurement conditions used in this document
•
A temperature range from TA=25°C to TA=150°C is covered for the timings. Please note that
the IC operating conditions are specified from TA=-40°C to TA=125°C. Since switching times
decrease with lower temperature, no timing problems should occur when an appropriate
driver setting for high temperature has been selected. However, eventual over- or undershoot
resulting from improper impedance matching between pad drivers and external load may
increase at low temperature. The timing at TA=125°C is a little bit faster than that documented
in this guideline at TA=150°C.
•
If the user is interested in rise/fall time values at other temperatures, a linear interpolation
between 25°C and 150°C can be done. For temperatures below 25°C, a linear extrapolation
can be applied.
•
Electromagnetic emission is always measured at TA=25°C.
•
The supply voltage for pad drivers is 5.0V for measurements at TA=25°C.
•
The supply voltage for pad drivers is 4.5V for measurements at TA=150°C.
Load capacitors are selected in a way that together with the measurement probe capacitance of 8pF
total capacitance values of 18pF up to 55pF are reached. Table 1 shows the reference between real
loads and numbers given in the result diagrams. For easy reading, these capacitances are referred to
as 20, 30, 40 and 50 pF in the result diagrams.
Probe
capacitance
SMD load capacitor
Resulting physical Referred
C
capacitance
8 pF
10 pF
18 pF
20 pF
8 pF
22 pF
30 pF
30 pF
8 pF
33 pF
41 pF
40 pF
8 pF
47 pF
55 pF
50 pF
Table 1: Overview of capacitive loads used for timing measurements
The result diagrams show
the measured rising and
falling edge timing using
an oscilloscope probe of
8pF||1MΩ. The reference
points are 10% and 90%
as indicated in Fig. 7.
For measurements at
TA=150°C, the pad supply
voltage VDDP has been
decreased
to
4.50V
(nominal VDDP minus
10%). Thus the voltage
levels
references for
timing measurements at
TA=150°C are: 0.45V (low
reference) and 4.05V
(high reference).
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Figure 7: Voltage level references for timing measurement
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3.1.2
Measured rise and fall times
The following diagrams show the 10-90%
rise times and 90-10% fall times of all
CLKOUT and GPIO driver strengths at
TA=25°C and TA=150°C. The physically
connected load capacitor values are
according the “Referred capacitances”
listed in Table 1. The abbreviations used
for driver strangth and load description
are listed in Table 2. The respective load
capacitor is connected close to the pin of
the CLKOUT or GPIO driver pin. It is
connected from the pin to GND. GPIO
measurements have been done at Port
3.13 of the XC161CS and are valid for all
other GPIO pins of the XC166 Family
members fabricated in 0.25µm CMOS
technology.
In Fig. 8-13 the rise and fall times are
given for CLKOUT and GPIO set to
different driver strengths. Fig. 14-23
extrapolate
the
measurement
temperatures of 25°C and 150°C down to
-40°C in a linear way (which reflects
reality with good approximation).
Abbreviation
Driver strength
Resulting physical
capacitor
SSH-20pF
Strong-sharp
18 pF
SSH-30pF
Strong-sharp
30 pF
SSH-40pF
Strong-sharp
41 pF
SSH-50pF
Strong-sharp
55 pF
SME-20pF
Strong-medium 18 pF
SME-30pF
Strong-medium 30 pF
SME-40pF
Strong-medium 41 pF
SME-50pF
Strong-medium 55 pF
SSO-20pF
Strong-soft
18 pF
SSO-30pF
Strong-soft
30 pF
SSO-40pF
Strong-soft
41 pF
SSO-50pF
Strong-soft
55 pF
MED-20pF
Medium
18 pF
MED-30pF
Medium
30 pF
MED-40pF
Medium
41 pF
MED-50pF
Medium
55 pF
WEA-20pF
Weak
18 pF
WEA-30pF
Weak
30 pF
WEA-40pF
Weak
41 pF
WEA-50pF
Weak
55 pF
Table 2: Abbreviations used in the timing result
diagrams
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Figure 8: Timings CLKOUT for all driver settings
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Figure 9: Zoomed timings CLKOUT for strong and medium driver settings
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Figure 10: Timings GPIO for all driver settings
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Figure 11: Zoomed timings GPIO for strong and medium driver settings
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Figure 12: Zoomed rise times CLKOUT and GPIO for strong and medium driver settings
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Figure 13: Zoomed fall times CLKOUT and GPIO for strong and medium driver settings
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Figure 14: CLKOUT “strong-sharp” driver rise/fall times over full ambient temperature range
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Figure 15: CLKOUT “strong-medium” driver rise/fall times over full ambient temperature range
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Figure 16: CLKOUT “strong-soft” driver rise/fall times over full ambient temperature range
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Figure 17: CLKOUT “medium” driver rise/fall times over full ambient temperature range
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Figure 18: CLKOUT “weak” driver rise/fall times over full ambient temperature range
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Figure 19: GPIO “strong-sharp” driver rise/fall times over full ambient temperature range
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Figure 20: GPIO “strong-medium” driver rise/fall times over full ambient temperature range
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Figure 21: GPIO “strong-soft” driver rise/fall times over full ambient temperature range
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Figure 22: GPIO “medium” driver rise/fall times over full ambient temperature range
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Figure 23: GPIO “weak” driver rise/fall times over full ambient temperature range
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4
Simulated Timings
4.1
Simulated timings on selected PCB trace structures
4.1.1
Description of structures
A temperature range from TA=25°C to
TA=150°C is covered for the timings.
Please note that in addition to the
measured timings, which use discrete
load capacitors, it is interesting to
compare timing waveforms for various
PCB structures. This overview provides
a good guess on the impact of serial
termination, the use of via contacts,
and the shape of trace structures
connected to a pad driver.
We use 4 different structures, shown in
Fig. 24:
(a) Point-to-Point,
(b) Bus,
(c) Star,
(d) Tree.
Each of the structures was drawn in 4
versions and simulated with Sigrity
Speed2000™. The 4 versions are:
(1) no vias, no series termination,
(2) no vias, series termination at
transmitter,
(3) vias, no series termination,
(4) vias, series termination.
In case of no vias, all traces are routed
on the top PCB layer where transmitter
and receivers are soldered. In case of
vias, the red traces in Fig. 24 are
routed on the bottom PCB layer. In
case of series termination, a 51Ω
resistor Rt is connected directly at the
transmitter output in the data line.
Figure 24: Set of PCB trace structures
The layer stack of the printed circuit board model is shown in Fig. 25. It consists of 4 layers in
standard FR4 material in the order signal-GND-VCC-signal.
300µm trace width results in a 57Ω
trace impedance.
The capacitance per unit length is
1pF/cm.
An input capacitance of 5pF per CMOS
receiver input is assumed.
The driver is represented by the IBIS
model listed in Appendix A. The driver
strength can be selected to be “strongsharp”, “strong-medium”, “strong-soft”,
“medium” and “weak”.
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Figure 25: PCB layer stack
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The length of each trace piece marked “l” in Fig.
24 has been dimensioned such that the
resulting total trace capacitance plus the
receiver gate capacitances are 20pF, 30pF,
40pF and 50pF. Table 3 lists the resulting trace
lengths. The via contacts connect signals on the
top layer with signals on the bottom layer.
Length “l”
Width “w”
Load
20 pF
5.1 cm
300 µm
30 pF
8.5 cm
300 µm
40pF
11.9 cm
300 µm
50 pF
15.3 cm
300 µm
Bus
20 pF
4.4 cm
300 µm
30 pF
7.9 cm
300 µm
40 pF
12.5 cm
300 µm
50 pF
16.8 cm
300 µm
Star
20 pF
4.2 cm
300 µm
30 pF
8.1 cm
300 µm
40 pF
12.2 cm
300 µm
50 pF
16.9 cm
300 µm
Tree
20 pF
5.9 cm
300 µm
30 pF
11.4 cm
300 µm
40 pF
17.2 cm
300 µm
50 pF
21.3 cm
300 µm
Table 3: Dimensions of PCB structures
Structure
Point-toPoint
Fig. 26-57 show the simulated rise and fall times
as a function of PCB structures with different
capacitive loads. In each diagram, the
measured timings and the simulated timings
with ideal capacitive load are given for
reference.
To keep a better overview, one diagram
contains only the curves for one structure
operating at one temperature. The parameters
varied in one diagram are the load capacitance
and the driver settings. The abbreviations are as
defined in Table 2.
4.1.2
Rise/fall time diagrams
All rise/fall times refer to the 10-90% rising edge and to the 90-10% falling edge of the transmitter
output voltage. Details are identical to the measured timings and levels described in chapter 3.1.1.
Weak driver strength has not been simulated because of the very low rise and fall times. Main
purpose is to show the influence of via contacts which are placed on the traces, and series
termination resistors placed at the driver outputs.
The 4 via/termination combinations are marked in the diagrams as follows:
“Vias No Term No” = no via contacts, no termination resistor
“Vias Yes Term No” = via contacts, but no termination resistor
“Vias No Term Yes” = no via contacts, but termination resistor
“Vias Yes Term Yes” = via contacts and termination resistor
Application Note AP16099
29
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 26: CLKOUT rise times for “Point-to-Point” layout at 25°C
Application Note AP16099
30
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 27: CLKOUT rise times for “Point-to-Point” layout at 150°C
Application Note AP16099
31
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 28: CLKOUT fall times for “Point-to-Point” layout at 25°C
Application Note AP16099
32
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 29: CLKOUT fall times for “Point-to-Point” layout at 150°C
Application Note AP16099
33
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 30: CLKOUT rise times for “Star” layout at 25°C
Application Note AP16099
34
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 31: CLKOUT rise times for “Star” layout at 150°C
Application Note AP16099
35
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 32: CLKOUT fall times for “Star” layout at 25°C
Application Note AP16099
36
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 33: CLKOUT fall times for “Star” layout at 150°C
Application Note AP16099
37
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 34: CLKOUT rise times for “Tree” layout at 25°C
Application Note AP16099
38
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 35: CLKOUT rise times for “Tree” layout at 150°C
Application Note AP16099
39
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 36: CLKOUT fall times for “Tree” layout at 25°C
Application Note AP16099
40
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 37: CLKOUT fall times for “Tree” layout at 150°C
Application Note AP16099
41
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 38: CLKOUT rise times for “Bus” layout at 25°C
Application Note AP16099
42
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 39: CLKOUT rise times for “Bus” layout at 150°C
Application Note AP16099
43
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 40: CLKOUT fall times for “Bus” layout at 25°C
Application Note AP16099
44
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 41: CLKOUT fall times for “Bus” layout at 150°C
Application Note AP16099
45
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 42: GPIO rise times for “Point-to-Point” layout at 25°C
Application Note AP16099
46
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 43: GPIO rise times for “Point-to-Point” layout at 150°C
Application Note AP16099
47
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 44: GPIO fall times for “Point-to-Point” layout at 25°C
Application Note AP16099
48
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 45: GPIO fall times for “Point-to-Point” layout at 150°C
Application Note AP16099
49
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 46: GPIO rise times for “Star” layout at 25°C
Application Note AP16099
50
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 47: GPIO rise times for “Star” layout at 150°C
Application Note AP16099
51
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 48: GPIO fall times for “Star” layout at 25°C
Application Note AP16099
52
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 49: GPIO fall times for “Star” layout at 150°C
Application Note AP16099
53
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 50: GPIO rise times for “Tree” layout at 25°C
Application Note AP16099
54
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 51: GPIO rise times for “Tree” layout at 150°C
Application Note AP16099
55
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 52: GPIO fall times for “Tree” layout at 25°C
Application Note AP16099
56
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 53: GPIO fall times for “Tree” layout at 150°C
Application Note AP16099
57
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 54: GPIO rise times for “Bus” layout at 25°C
Application Note AP16099
58
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 55: GPIO rise times for “Bus” layout at 150°C
Application Note AP16099
59
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 56: GPIO fall times for “Bus” layout at 25°C
Application Note AP16099
60
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Figure 57: GPIO fall times for “Bus” layout at 150°C
Application Note AP16099
61
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
4.1.3
Rise/fall waveforms
The following waveforms result from Speed2000™ timing simulations of the PCB structures
described in chapter 4.1.1. Since the waveforms of the different structures are very similar, only
“point-to-point” and “bus” structures are presented here with loads of 20pF and 40pF. However, the
influence of via contacts and termination resistors is visible from the waveforms.
Each of Fig. 59-90 contains 4 waveforms for a given pad type (CLKOUT or GPOI), a given ambient
temperature (25°C or 150°C) and a given driver strength. Depending on these settings, certain clock
frequencies can be driven or not. The waveforms show one of 3 frequencies: 10MHz, 5MHz or
2.5MHz – whatever is the highest frequency for a given setting which shows an acceptable signal
integrity (i.e. high and low voltage levels of 5.0V and 0.0V are reached during switching).
The 4 configurations shown in one figure are distributed as follows:
20pF Capacitive Load
40pF Capacitive Load
No Termination Resistor
No Termination Resistor
20pF Capacitive Load
40pF Capacitive Load
51Ω Termination Resistor
51Ω Termination Resistor
Figure 58: General grouping of waveform configurations
Application Note AP16099
62
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT 25°C P2P w/ Vias w/o Term 20pF Strong-Sharp
CLKOUT 25°C P2P w/ Vias w/o Term 40pF Strong-Sharp
8.0V
8.0V
7.0V
7.0V
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
-1.0V
-2.0V
-2.0V
-3.0V
-3.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-4.0V
000.0E+0s
140.0E-9s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
CLKOUT 25°C P2P w/ Vias w/ Term 40pF Strong-Sharp
CLKOUT 25°C P2P w/ Vias w/ Term 20pF Strong-Sharp
6.0V
-1.0V
000.0E+0s
20.0E-9s
-1.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 59: Waveforms CLKOUT 20 MHz “Strong-Sharp” / “Point-to-Point” at 25°C ambient temperature
CLKOUT 25°C Bus w/ vias w/o Term 40pF Strong-Sharp
CLKOUT 25°C Bus w/ Vias w/o Term 20pF Strong-Sharp
7.0V
10.0V
6.0V
8.0V
5.0V
6.0V
4.0V
4.0V
3.0V
2.0V
2.0V
1.0V
0.0V
0.0V
-2.0V
-1.0V
-4.0V
-2.0V
-3.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-6.0V
000.0E+0s
140.0E-9s
CLKOUT 25°C Bus w/ Vias w/ Term 20pF Strong-Sharp
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
CLKOUT 25°C Bus w/ Vias w/ Term 40pF Strong-Sharp
6.0V
7.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
-1.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-2.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 60: Waveforms CLKOUT 20 MHz “Strong-Sharp” / “Bus” at 25°C ambient temperature
Application Note AP16099
63
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT 150°C P2P w/ Vias w/o Term 40pF Strong-Sharp
CLKOUT 150°C P2P w/ Vias w/o Term 20pF Strong-Sharp
7.0V
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
-1.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-2.0V
000.0E+0s
140.0E-9s
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
CLKOUT 150°C P2P w/ Vias w/ Term 20pF Strong-Sharp
CLKOUT 150°C P2P w/ Vias w/ Term 20pF Strong-Sharp
-1.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 61: Waveforms CLKOUT 20 MHz “Strong-Sharp” / “Point-to-Point” at 150°C ambient temperat.
CLKOUT 150°C Bus w/ Vias w/o Term 40pF Strong-Sharp
CLKOUT 150°C Bus w/ Vias w/o Term 20pF Strong-Sharp
8.0V
6.0V
7.0V
5.0V
6.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
-1.0V
0.0V
-2.0V
-1.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-3.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
CLKOUT 150°C Bus w/ Vias w/ Term 40pF Strong-Sharp
CLKOUT 150°C Bus w/ Vias w/ Term 20pF Strong-Sharp
7.0V
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
-1.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
-2.0V
000.0E+0s
100.0E-9s 120.0E-9s 140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 62: Waveforms CLKOUT 20 MHz “Strong-Sharp” / “Bus” at 150°C ambient temperature
Application Note AP16099
64
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT 25°C P2P w/ Vias w/o Term 40pF Strong-Medium
CLKOUT 25°C P2P w/ Vias w/o Term 20pF Strong-Medium
7.0V
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
0.0V
1.0V
-1.0V
0.0V
-2.0V
-1.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-3.0V
000.0E+0s
140.0E-9s
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
CLKOUT 25°C P2P w/ Vias w/ Term 40pF Strong-Medium
CLKOUT 25°C P2P w/ Vias w/ Term 20pF Strong-Medium
-1.0V
000.0E+0s
20.0E-9s
-1.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 63: Waveforms CLKOUT 20 MHz “Strong-Medium” / “Point-to-Point” 25°C ambient temperature
CLKOUT 25°C Bus w/ Vias w/o Term 40pF Strong-Medium
CLKOUT 25°C Bus w/ Vias w/o Term 20pF Strong-Medium
8.0V
7.0V
7.0V
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
-1.0V
-2.0V
-2.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-3.0V
000.0E+0s
140.0E-9s
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
CLKOUT 25°C Bus w/ Vias w/ Term 40pF Strong Medium
CLKOUT 25°C Bus w/ Vias w/ Term 20pF Strong Medium
-1.0V
000.0E+0s
20.0E-9s
-1.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 64: Waveforms CLKOUT 20 MHz “Strong-Medium” / “Bus” at 25°C ambient temperature
Application Note AP16099
65
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT 150°C P2P w/ Vias w/o Term 40pF Strong-Medium
CLKOUT 150°C P2P w/ Vias w/o Term 20pF Strong-Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-1.0V
000.0E+0s
140.0E-9s
CLKOUT 150°C P2P w/ Vias w/ Term 20pF Strong-Medium
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
CLKOUT 150°C P2P w/ Vias w/ Term 40pF Strong-Medium
6.0V
-1.0V
000.0E+0s
20.0E-9s
-1.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 65: Waveforms CLKOUT 20 MHz “Strong-Medium” / “Point-to-Point” at 150°C ambient temper.
CLKOUT 150°C Bus w/ Vias w/o Term 40pF Strong-Medium
CLKOUT 150°C Bus w/ Vias w/o Term 20pF Strong-Medium
6.0V
7.0V
5.0V
6.0V
4.0V
5.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
-1.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-2.0V
000.0E+0s
140.0E-9s
CLKOUT 150°C Bus w/ Vias w/ Term 20pF Strong-Medium
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
CLKOUT 150°C Bus w/ Vias w/ Term 40pF Strong-Medium
6.0V
-1.0V
000.0E+0s
20.0E-9s
-1.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s 120.0E-9s 140.0E-9s
Figure 66: Waveforms CLKOUT 20 MHz “Strong-Medium” / “Bus” at 150°C ambient temperature
Application Note AP16099
66
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT 25°C P2P w/ Vias w/o Term 40pF Strong-Soft
CLKOUT 25°C P2P w/ Vias w/o Term 20pF Strong-Soft
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
CLKOUT 25°C P2P w/ Vias w/ Term 40pF Strong-Soft
CLKOUT 25°C P2P w/ Vias w/ Term 20pF Strong-Soft
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 67: Waveforms CLKOUT 10 MHz “Strong-Soft” / “Point-to-Point” at 25°C ambient temperature
CLKOUT 25°C Bus w/ Vias w/o Term 40pF Strong-Soft
CLKOUT 25°C Bus w/ Vias w/o Term 20pF Strong-Soft
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0
CLKOUT 25°C Bus w/ Vias w/ Term 20pF Strong-Soft
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9
150.0E-9
200.0E-9
250.0E-9
300.0E-9
CLKOUT 25°C Bus w/ Vias w/ Term 40pF Strong-Soft
6.0V
-1.0V
000.0E+0s
50.0E-9
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 68: Waveforms CLKOUT 10 MHz “Strong-Soft” / “Bus” at 25°C ambient temperature
Application Note AP16099
67
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT 150°C P2P w/ Vias w/o Term 40pF Strong-Soft
CLKOUT 150°C P2P w/ Vias w/o Term 20pF Strong-Soft
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
CLKOUT 150°C P2P w/ Vias w/ Term 40pF Strong-Soft
CLKOUT 150°C P2P w/ Vias w/ Term 20pF Strong-Soft
6.0V
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 69: Waveforms CLKOUT 10 MHz “Strong-Soft” / “Point-to-Point” at 150°C ambient temperature
CLKOUT 150°C Bus w/ Vias w/o Term 40pF Strong-Soft
CLKOUT 150°C Bus w/ Vias w/o Term 20pF Strong-Soft
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
CLKOUT 150°C Bus w/ Vias w/ Term 40pF Strong-Soft
CLKOUT 150°C Bus w/ Vias w/ Term 20pF Strong-Soft
6.0V
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 70: Waveforms CLKOUT 10 MHz “Strong-Soft” / “Bus” at 150°C ambient temperature
Application Note AP16099
68
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT 25°C P2P w/ Vias w/o Term 40pF Medium
CLKOUT 25°C P2P w/ Vias w/o Term 20pF Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
CLKOUT 25°C P2P w/ Vias w/ Term 40pF Medium
CLKOUT 25°C P2P w/ Vias w/ Term 20pF Medium
6.0V
-1.0V
000.0E+0s
100.0E-9s
600.0E-9s
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
Figure 71: Waveforms CLKOUT 5 MHz “Medium” / “Point-to-Point” at 25°C ambient temperature
CLKOUT 25°C Bus w/ Vias w/o Term 20pF Medium
CLKOUT 25°C Bus w/ Vias w/o Term 40pF Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
CLKOUT 25°C Bus w/ Vias w/ Term 40pF Medium
CLKOUT 25°C Bus w/ Vias w/ Term 20pF Medium
6.0V
-1.0V
000.0E+0s
100.0E-9s
600.0E-9s
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
Figure 72: Waveforms CLKOUT 5 MHz “Medium” / “Bus” at 25°C ambient temperature
Application Note AP16099
69
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT 150°C P2P w/ Vias w/o Term 40pF Medium
CLKOUT 150°C P2P w/ Vias w/o Term 20pF Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
-1.0V
000.0E+0s
CLKOUT 150°C P2P w/ Vias w/ Term 20pF Medium
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
CLKOUT 150°C P2P w/ Vias w/ Term 40pF Medium
6.0V
-1.0V
000.0E+0s
100.0E-9s
600.0E-9s
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
Figure 73: Waveforms CLKOUT 5 MHz “Medium” / “Point-to-Point” at 150°C ambient temperature
CLKOUT 150°C Bus w/ Vias w/o Term 40pF Medium
CLKOUT 150°C Bus w/ Vias w/o Term 20pF Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
-1.0V
000.0E+0s
CLKOUT 150°C Bus w/ Vias w/ Term 20pF Medium
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
CLKOUT 150°C Bus w/ Vias w/ Term 40pF Medium
6.0V
-1.0V
000.0E+0s
100.0E-9s
600.0E-9s
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
Figure 74: Waveforms CLKOUT 5 MHz “Medium” / “Bus” at 150°C ambient temperature
Application Note AP16099
70
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO 25°C P2P w/ Vias w/o Term 40pF Strong-Sharp
GPIO 25°C P2P w/ Vias w/o Term 20pF Strong-Sharp
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
-1.0V
-2.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-2.0V
000.0E+0s
140.0E-9s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
GPIO 25°C P2P w/ Vias w/ Term 40pF Strong-Sharp
GPIO 25°C P2P w/ Vias w/ Term 20pF Strong-Sharp
6.0V
-1.0V
000.0E+0s
20.0E-9s
-1.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 75: Waveforms GPIO 20 MHz “Strong-Sharp” / “Point-to-Point” at 25°C ambient temperature
GPIO 25°C Bus w/ Vias w/o Term 40pF Strong-Sharp
GPIO 25°C Bus w/ Vias w/o Term 20pF Strong-Sharp
8.0V
7.0V
7.0V
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
-1.0V
-2.0V
000.0E+0s
-2.0V
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-3.0V
000.0E+0s
140.0E-9s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
GPIO 25°C Bus w/ Vias w/ Term 40pF Strong-Sharp
GPIO 25°C Bus w/ Vias w/ Term 20pF Strong-Sharp
6.0V
-1.0V
000.0E+0s
20.0E-9s
-1.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 76: Waveforms GPIO 20 MHz “Strong-Sharp” / “Bus” at 25°C ambient temperature
Application Note AP16099
71
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO 150°C P2P w/ Vias w/o Term 40pF Strong-Sharp
GPIO 150°C P2P w/ Vias w/o Term 20pF Strong-Sharp
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-1.0V
000.0E+0s
140.0E-9s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
GPIO 150°C P2P w/ Vias w/ Term 40pF Strong-Sharp
GPIO 150°C P2P w/ Vias w/ Term 20pF Strong-Sharp
6.0V
-1.0V
000.0E+0s
20.0E-9s
-1.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 77: Waveforms GPIO 20 MHz “Strong-Sharp” / “Point-to-Point” at 150°C ambient temperature
GPIO 150°C Bus w/ Vias w/o Term 20pF Strong-Sharp
GPIO 150°C Bus w/ Vias w/o Term 40pF Strong-Sharp
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
-1.0V
000.0E+0s
140.0E-9s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
GPIO 150°C Bus w/ Vias w/ Term 40pF Strong-Sharp
GPIO 150°C Bus w/ Vias w/ Term 20pF Strong-Sharp
6.0V
-1.0V
000.0E+0s
20.0E-9s
-1.0V
000.0E+0s
140.0E-9s
20.0E-9s
40.0E-9s
60.0E-9s
80.0E-9s
100.0E-9s
120.0E-9s
140.0E-9s
Figure 78: Waveforms GPIO 20 MHz “Strong-Sharp” / “Bus” at 150°C ambient temperature
Application Note AP16099
72
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO 25°C P2P w/ Vias w/o Term 40pF Strong-Medium
GPIO 25°C P2P w/ Vias w/o Term 20pF Strong-Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
GPIO 25°C P2P w/ Vias w/ Term 40pF Strong-Medium
GPIO 25°C P2P w/ Vias w/ Term 20pF Strong-Medium
6.0V
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 79: Waveforms GPIO 10 MHz “Strong-Medium” / “Point-to-Point” at 25°C ambient temperature
GPIO 25°C Bus w/ Vias w/o Term 40pF Strong-Medium
GPIO 25°C Bus w/ Vias w/o Term 20pF Strong-Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
GPIO 25°C Bus w/ Vias w/ Term 40pF Strong-Medium
GPIO 25°C Bus w/ Vias w/ Term 20pF Strong-Medium
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 80: Waveforms GPIO 10 MHz “Strong-Medium” / “Bus” at 25°C ambient temperature
Application Note AP16099
73
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO 150°C P2P w/ Vias w/o Term 20pF Strong-Medium
GPIO 150°C P2P w/ Vias w/o Term 40pF Strong-Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
GPIO 150°C P2P w/ Vias w/ Term 20pF Strong-Medium
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
GPIO 150°C Bus w/ Vias w/ Term 40pF Strong-Medium
6.0V
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 81: Waveforms GPIO 10 MHz “Strong-Medium” / “Point-to-Point” at 150°C ambient temperature
GPIO 150°C Bus w/ Vias w/o Term 40pF Strong-Medium
GPIO 150°C Bus w/ Vias w/o Term 20pF Strong-Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
GPIO 150°C Bus w/ Vias w/ Term 20pF Strong-Medium
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
GPIO 150°C Bus w/ Vias w/ Term 40pF Strong-Medium
6.0V
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 82: Waveforms GPIO 10 MHz “Strong-Medium” / “Bus” at 150°C ambient temperature
Application Note AP16099
74
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO 25°C P2P w/ Vias w/o Term 40pF Strong-Soft
GPIO 25°C P2P w/ Vias w/o Term 20pF Strong-Soft
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
GPIO 25°C P2P w/ Vias w/ Term 40pF Strong-Soft
GPIO 25°C P2P w/ Vias w/ Term 20pF Strong-Soft
6.0V
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 83: Waveforms GPIO 10 MHz “Strong-Soft” / “Point-to-Point” at 25°C ambient temperature
GPIO 25°C Bus w/ Vias w/o Term 40pF Strong-Soft
GPIO 25°C Bus w/ Vias w/o Term 20pF Strong-Soft
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
GPIO 25°C Bus w/ Vias w/ Term 40pF Strong-Soft
GPIO 25°C Bus w/ Vias w/ Term 20pF Strong-Soft
6.0V
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 84: Waveforms GPIO 10 MHz “Strong-Soft” / “Bus” at 25°C ambient temperature
Application Note AP16099
75
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO 150°C P2P w/ Vias w/o Term 40pF Strong-Soft
GPIO 150°C P2P w/ Vias w/o Term 20pF Strong-Soft
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
GPIO 150°C P2P w/ Vias w/ Term 40pF Strong-Soft
GPIO 150°C P2P w/ Vias w/ Term 20pF Strong-Soft
6.0V
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 85: Waveforms GPIO 10 MHz “Strong-Soft” / “Point-to-Point” at 150°C ambient temperature
GPIO 150°C Bus w/ Vias w/o Term 20pF Strong-Soft
GPIO 150°C Bus w/ Vias w/o Term 40pF Strong-Soft
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
GPIO 150°C Bus w/ Vias w/ Term 40pF Strong-Soft
GPIO 150°C Bus w/ Vias w/ Term 20pF Strong-Soft
6.0V
-1.0V
000.0E+0s
50.0E-9s
300.0E-9s
-1.0V
000.0E+0s
50.0E-9s
100.0E-9s
150.0E-9s
200.0E-9s
250.0E-9s
300.0E-9s
Figure 86: Waveforms GPIO 10 MHz “Strong- Soft” / “Bus” at 150°C ambient temperature
Application Note AP16099
76
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO 25°C P2P w/ Vias w/o Term 40pF Medium
GPIO 25°C P2P w/ Vias w/o Term 20pF Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
-1.0V
000.0E+0s
GPIO 25°C P2P w/ Vias w/ Term 20pF Medium
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
GPIO 25°C P2P w/ Vias w/ Term 40pF Medium
6.0V
-1.0V
000.0E+0s
100.0E-9s
600.0E-9s
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
Figure 87: Waveforms GPIO 5 MHz “Medium” / “Point-to-Point” at 25°C ambient temperature
GPIO 25°C Bus w/ Vias w/o Term 40pF Medium
GPIO 25°C Bus w/ Vias w/o Term 20pF Strong-Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
-1.0V
000.0E+0s
GPIO 25°C Bus w/ Vias w/ Term 20pF Medium
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
GPIO 25°C Bus w/ Vias w/ Term 40pF Medium
6.0V
-1.0V
000.0E+0s
100.0E-9s
600.0E-9s
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
Figure 88: Waveforms GPIO 5 MHz “Medium” / “Bus” at 25°C ambient temperature
Application Note AP16099
77
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO 150°C P2P w/ Vias w/o Term 40pF Medium
GPIO 150°C P2P w/ Vias w/o Term 20pF Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
GPIO 150°C P2P w/ Vias w/ Term 40pF Medium
GPIO 150°C P2P w/ Vias w/ Term 20pF Medium
6.0V
-1.0V
000.0E+0s
100.0E-9s
600.0E-9s
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
Figure 89: Waveforms GPIO 5 MHz “Medium” / “Point-to-Point” at 150°C ambient temperature
GPIO 150°C Bus w/ Vias w/o Term 20pF Medium
GPIO 150°C Bus w/ Vias w/o Term 40pF Medium
6.0V
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
-1.0V
000.0E+0s
6.0V
5.0V
5.0V
4.0V
4.0V
3.0V
3.0V
2.0V
2.0V
1.0V
1.0V
0.0V
0.0V
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
GPIO 150°C Bus w/ Vias w/ Term 40pF Medium
GPIO 150°C Bus w/ Vias w/ Term 20pF Medium
6.0V
-1.0V
000.0E+0s
100.0E-9s
600.0E-9s
-1.0V
000.0E+0s
100.0E-9s
200.0E-9s
300.0E-9s
400.0E-9s
500.0E-9s
600.0E-9s
Figure 90: Waveforms GPIO 5 MHz “Medium” / “Bus” at 150°C ambient temperature
Application Note AP16099
78
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
5
Measured Electromagnetic Emission
In addition to signal integrity, the scaling of pad drivers helps to reduce electromagnetic emission
(EME) caused by switching output pins. This is because slower signal edges produce less high
frequency contents in the emission spectra.
The following rule should be obeyed when selecting pad driver strength:
Use the weakest/slowest driver setting which provides the required signal timing at worst-case
operating conditions.
Worst-case operating conditions are:
-
maximum ambient temperature (e.g. +125°C)
-
minimum pad supply voltage (e.g. 4.50V)
-
realistic capacitive output load (consider trace length, trace structure, connected receiver
input loads)
To illustrate the benefits of driver scaling for low EME, some sample measurement results are
provided.
The measurements have been performed under two operating conditions:
Operating condition 1:
CLKOUT toggling at 40MHz with capacitive loads of 0pF, 10pF, 22pF, 33pF, 47pF.
All GPIOs inactive.
Core running in idle loop.
Conducted emission measured at pad supply (VDDP) and core supply (VDDC) according to chapter
5.1.1.
Radiated emission measured in mini-TEM cell according to chapter 5.1.2.
Operating condition 2:
GPIOs toggling at ca. 700kHz with capacitive loads of 0pF, 22pF, 47pF.
Toggling pins are: Port2[15:0].
CLKOUT inactive.
Conducted emission measured at pad supply (VDDP) and core supply (VDDC) according to chapter
5.1.1.
Radiated emission measured in mini-TEM cell according to chapter 5.1.2.
Please note that all emission peaks visible between 900 MHz and 1000 MHz result from cellular
phone activity and should be ignored when assessing the IC-related emission.
5.1
Description of test equipment
5.1.1
Conducted emission
configuration
test
Conducted emission is measured using the
standardized 150Ω network, see Fig. 91.
This network is used for both port and
power supply emission measurements. For
reference purpose, only the emission
measured at the supply domains VDDP
(5.0V pad supply) and VDDC (2.5V core
supply)
are
documented.
Emission
reduction can be observed in a similar way
on passive (i.e. non-switching) pad pins.
150Ω networks are provided for conducted
emission measurements according IEC
61967 part 4 and BISS emission test
specification.
For the measurements the probing points
shown in Fig. 91 connected to VDD1 (is
VDDC) and VDD2 (is VDDP) are used. No
testing was performed at passive I/Os.
Application Note AP16099
Figure 91: Conducted emission probing points
79
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
5.1.2
Radiated emission test configuration
Radiated emission is measured using the standard Mini TEM Cell according IEC 61967 part 2 and
BISS emission test specification. The frequency range is from 150kHz to 1000MHz.
Figure 92: Radiated emission test setup
5.1.3
Instruments and software for emission data recognition
Spectrum analyzer:
Advantest R3361C
Detector type:
Peak detector
Measurement time:
For all measurements, the emission measurement time (10ms) at one
frequency is longer than the test software loop duration.
Pre-Amplifier:
Advantest R14601A
Data generation software:
Rohde&Schwarz EMIPAK 9950
Environment:
temperature 23°C ±5°C
Supply:
nominal voltage ±5%
For all measurements the noise floor is at least 6dB below the limit.
Spectrum Analyzer
TEM
150 Ω
Frequency range
RBW
150 kHz
to
30 MHz
30 MHz
to
200 MHz
200 MHz
to
1000 MHz
Sweep time*
10kHz
ts =
100kHz
NP ⋅ LT ⋅ FR
RBW
Table 4: Spectrum analyzer settings for EME measurements
*) NP=number of points; LT=loop time; FR=frequency range
Application Note AP16099
80
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
5.2
Emission measurement results
CLKOUT Strong-Sharp no Load VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 93: CLKOUT „Strong-Sharp“ driver at 0pF load – conducted emission on VDDP
CLKOUT Strong-Sharp no Load VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 94: CLKOUT „Strong-Sharp“ driver at 0pF load – conducted emission on VDDC
Application Note AP16099
81
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT Strong-Sharp 10pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 95: CLKOUT „Strong-Sharp“ driver at 10pF load – conducted emission on VDDP
CLKOUT Strong-Sharp 10pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 96: CLKOUT „Strong-Sharp“ driver at 10pF load – conducted emission on VDDC
Application Note AP16099
82
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT Strong-Sharp 22pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 97: CLKOUT „Strong-Sharp“ driver at 22pF load – conducted emission on VDDP
CLKOUT Strong-Sharp 22pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 98: CLKOUT „Strong-Sharp“ driver at 22pF load – conducted emission on VDDC
Application Note AP16099
83
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT Strong-Sharp 33pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 99: CLKOUT „Strong-Sharp“ driver at 33pF load – conducted emission on VDDP
CLKOUT Strong-Medium 33pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 100: CLKOUT „Strong-Sharp“ driver at 33pF load – conducted emission on VDDC
Application Note AP16099
84
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT Strong-Sharp 47pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 101: CLKOUT „Strong-Sharp“ driver at 47pF load – conducted emission on VDDP
CLKOUT Strong-Sharp 47pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 102: CLKOUT „Strong-Sharp“ driver at 47pF load – conducted emission on VDDC
Application Note AP16099
85
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT Strong-Medium no Load VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 103: CLKOUT „Strong-Medium“ driver at 0pF load – conducted emission on VDDP
CLKOUT Strong-Medium no Load VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 104: CLKOUT „Strong-Medium“ driver at 0pF load – conducted emission on VDDC
Application Note AP16099
86
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT Strong-Medium 10pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 105: CLKOUT „Strong-Medium“ driver at 10pF load – conducted emission on VDDP
CLKOUT Strong-Medium 10pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 106: CLKOUT „Strong-Medium“ driver at 10pF load – conducted emission on VDDC
Application Note AP16099
87
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT Strong-Medium 22pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 107: CLKOUT „Strong-Medium“ driver at 22pF load – conducted emission on VDDP
CLKOUT Strong-Medium 22pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 108: CLKOUT „Strong-Medium“ driver at 22pF load – conducted emission on VDDC
Application Note AP16099
88
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT Strong-Medium 33pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 109: CLKOUT „Strong-Medium“ driver at 33pF load – conducted emission on VDDP
CLKOUT Strong-Medium 33pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 110: CLKOUT „Strong-Medium“ driver at 33pF load – conducted emission on VDDC
Application Note AP16099
89
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT Strong-Medium 47pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 111: CLKOUT „Strong-Medium“ driver at 47pF load – conducted emission on VDDP
CLKOUT Strong-Medium 47pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 112: CLKOUT „Strong-Medium“ driver at 47pF load – conducted emission on VDDC
Application Note AP16099
90
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Strong-Sharp no Load VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 113: GPIO „Strong-Sharp“ driver at 0pF load – conducted emission on VDDP
GPIO Strong-Sharp no Load VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 114: GPIO „Strong-Sharp“ driver at 0pF load – conducted emission on VDDC
Application Note AP16099
91
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Strong-Sharp 22pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 115: GPIO „Strong-Sharp“ driver at 22pF load – conducted emission on VDDP
GPIO Strong-Sharp 22pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 116: GPIO „Strong-Sharp“ driver at 22pF load – conducted emission on VDDC
Application Note AP16099
92
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Strong-Sharp 47pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 117 GPIO „Strong-Sharp“ driver at 47pF load – conducted emission on VDDP
GPIO Strong-Sharp 47pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 118: GPIO „Strong-Sharp“ driver at 47pF load – conducted emission on VDDC
Application Note AP16099
93
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Strong-Medium no Load VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 119: GPIO „Strong-Medium“ driver at 0pF load – conducted emission on VDDP
GPIO Strong-Medium no Load VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 120: GPIO „Strong-Medium“ driver at 0pF load – conducted emission on VDDC
Application Note AP16099
94
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Strong-Medium 22pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 121: GPIO „Strong-Medium“ driver at 22pF load – conducted emission on VDDP
GPIO Strong-Medium 22pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 122: GPIO „Strong-Medium“ driver at 22pF load – conducted emission on VDDC
Application Note AP16099
95
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Strong-Medium 47pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 123: GPIO „Strong-Medium“ driver at 47pF load – conducted emission on VDDP
GPIO Strong-Medium 47pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 124: GPIO „Strong-Medium“ driver at 47pF load – conducted emission on VDDC
Application Note AP16099
96
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Strong-Soft no Load VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 125: GPIO „Strong-Soft“ driver at 0pF load – conducted emission on VDDP
GPIO Strong-Soft no Load VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 126: GPIO „Strong-Soft“ driver at 0pF load – conducted emission on VDDC
Application Note AP16099
97
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Strong-Soft 22pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 127: GPIO „Strong-Soft“ driver at 22pF load – conducted emission on VDDP
GPIO Strong-Soft 22pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 128: GPIO „Strong-Soft“ driver at 22pF load – conducted emission on VDDC
Application Note AP16099
98
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Strong-Soft 47pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 129: GPIO „Strong-Soft“ driver at 47pF load – conducted emission on VDDP
GPIO Strong-Soft 47pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 130: GPIO „Strong-Soft“ driver at 47pF load – conducted emission on VDDC
Application Note AP16099
99
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Medium no Load VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 131: GPIO „Medium“ driver at 0pF load – conducted emission on VDDP
GPIO Medium no Load VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 132: GPIO „Medium“ driver at 0pF load – conducted emission on VDDC
Application Note AP16099
100
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Medium 22pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 133: GPIO „Medium“ driver at 22pF load – conducted emission on VDDP
GPIO Medium 22pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 134: GPIO „Medium“ driver at 22pF load – conducted emission on VDDC
Application Note AP16099
101
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Medium 47pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 135: GPIO „Medium“ driver at 47pF load – conducted emission on VDDP
GPIO Medium 47pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 136: GPIO „Medium“ driver at 47pF load – conducted emission on VDDC
Application Note AP16099
102
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Weak no Load VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 137: GPIO „Weak“ driver at 0pF load – conducted emission on VDDP
GPIO Weak no Load VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 138: GPIO „Weak“ driver at 0pF load – conducted emission on VDDC
Application Note AP16099
103
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Weak 22pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 139: GPIO „Weak“ driver at 22pF load – conducted emission on VDDP
GPIO Weak 22pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 140: GPIO „Weak“ driver at 22pF load – conducted emission on VDDC
Application Note AP16099
104
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Weak 47pF VDDP
70
65
60
55
50
dBµV
45
40
35
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 141: GPIO „Weak“ driver at 47pF load – conducted emission on VDDP
GPIO Weak 47pF VDDC
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 142: GPIO „Weak“ driver at 47pF load – conducted emission on VDDC
Application Note AP16099
105
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT Strong-Sharp no Load RE
GPIO Strong-Sharp no Load RE
50
50
45
45
40
40
35
dBµV
dBµV
35
30
30
25
25
20
20
15
15
10
10
5
5
0
0 0
0
100
200
300
400
500
600
700
800
900
1000
100
200
300
400Frequency/MHz
500
600
700
800
900
1000
Frequency/MHz
Figure 143: CLKOUT „Strong-Sharp“ driver at 0pF load – radiated emission
Figure 145: GPIO „Strong-Sharp“ driver at 0pF load – radiated emission
CLKOUT Strong-Medium no Load RE
GPIO Strong-Medium no Load RE
50
50
45
45
40
40
35
dBµV
dBµV
35
30
30
25
25
20
20
15
15
10
10
5
5
0
0 0
0
100
100
200
200
300
400
600
700
800
900
1000
300
400 Frequency/MHz
500
600
500
700
800
900
1000
Frequency/MHz
Figure 144: CLKOUT „Strong-Medium“ driver at 0pF load – radiated emission
Figure 146: GPIO „Strong-Medium“ driver at 0pF load – radiated emission
Application Note AP16099
106
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Strong-Soft no Load RE
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
900
1000
Frequency/MHz
Figure 147: GPIO „Strong-Soft“ driver at 0pF load – radiated emission
GPIO Medium no Load RE
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
Frequency/MHz
Figure 148: GPIO „Medium“ driver at 0pF load – radiated emission
Application Note AP16099
107
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
GPIO Weak no Load RE
50
45
40
35
dBµV
30
25
20
15
10
5
0
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 149: GPIO „Weak“ driver at 0pF load – radiated emission
Application Note AP16099
108
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
6
Result discussion
The emission results presented in chapter 5 need a closer discussion regarding the impact of pad
driver scaling and connected capacitive loads on the peak emission levels.
This discussion is based on selected comparison data extracted from the emission tests.
6.1
CLKOUT driver, conducted emission
CLKOUT uses a stronger driver than all other GPIOs. Its purpose is the distribution of the system
clock either original or divided. In the presented measurements, CLKOUT was operated at 40MHz,
which is equal to the system frequency. To maintain good signal integrity, no driver setting less than
strong-medium must be selected.
Fig. 150 compares the emissions coupled onto VDDC for strong-medium and strong-sharp settings
for CLKOUT while driving different load capacitors of 0pF (i.e. no load), 10pF, 22pF, 33pF and 47pF.
No additional probe capacitance was connected to the CLKOUT pin.
dBµV
CLKOUT crosstalk to VDDC
"Driver Setting and Load Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
STRONG-SHARP
Group Envelope
STRONG-MEDIUM
Group Envelope
0
100
200
300
400
500
600
700
800
CLKOUT SME 0pF VDDC
CLKOUT SME 10pF VDDC
CLKOUT SME 22pF VDDC
CLKOUT SME 33pF VDDC
CLKOUT SME 47pF VDDC
CLKOUT SSH 0pF VDDC
CLKOUT SSH 10pF VDDC
CLKOUT SSH 22pF VDDC
CLKOUT SSH 33pF VDDC
CLKOUT SSH 47pF VDDC
900
1000
Frequency/MHz
Figure 150: CLKOUT „Strong-Sharp“ and “strong-soft” driver at various loads –
conducted emission on VDDC
Using strong-medium instead of strong-sof driver setting for CLKOUT reduces the resulting emission
on VDDC up to 10dB.
Application Note AP16099
109
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Fig. 151 compares the emissions coupled onto VDDP for strong-medium and strong-sharp settings
for CLKOUT while driving different load capacitors of 0pF (i.e. no load), 10pF, 22pF, 33pF and 47pF.
No additional probe capacitance was connected to the CLKOUT pin.
dBµV
CLKOUT crosstalk to VDDP
"Driver Setting and Load Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
STRONG-SHARP
Group Envelope
STRONG-MEDIUM
Group Envelope
0
100
200
300
400
500
600
CLKOUT SME 0pF VDDP
CLKOUT SME 10pF VDDP
CLKOUT SME 22pF VDDP
CLKOUT SME 33pF VDDP
CLKOUT SME 47pF VDDP
CLKOUT SSH 0pF VDDP
CLKOUT SSH 10pF VDDP
CLKOUT SSH 22pF VDDP
CLKOUT SSH 33pF VDDP
CLKOUT SSH 47pF VDDP
700
800
900
1000
Frequency/MHz
Figure 151: CLKOUT „Strong-Sharp“ and “strong-soft” driver at various loads –
conducted emission on VDDP
Using strong-medium instead of strong-sof driver setting for CLKOUT reduces the resulting emission
on VDDP up to 15dB.
Application Note AP16099
110
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
6.2
GPIO drivers, conducted emission
GPIOs drive special peripheral functions up to a few MHz, but in real applications their data rates
stay mostly in the range of 10kHz up to some 100kHz. During our emission measurement, the port
switching was controlled by software. The resulting toggle rate was ca. 700kHz.
On VDDC, the crosstalk noise is mainly determined by the system clock and its derivatives. These
clocks determine the synchronous switching of internal logic gates. Thus the emission observed on
VDDC is mainly caused by the internal switching activity.
Fig. 152 compares the emission on VDDC for all possible driver settings at 22pF.
dBµV
GPIO with 22pF Load / Crosstalk to VDDC
"Driver Setting Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
GPIO WEA 22pF VDDC
GPIO MED 22pF VDDC
GPIO SSO 22pF VDDC
GPIO SME 22pF VDDC
GPIO SSH 22pF VDDC
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 152: GPIO various driver settings at 22pF load –
conducted emission on VDDC
From this result we see that the emission on VDDC is not influenced by the driver settings.
Application Note AP16099
111
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
On VDDP, the crosstalk noise might be determined by the switching ports activity. This is because all
pad drivers are connected to VDDP.
Fig. 153 compares the emission on VDDP for all possible driver settings at no external load.
dBµV
GPIO without Load / Crosstalk to VDDP
"Driver Setting Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
GPIO WEA 0pF VDDP
GPIO MED 0pF VDDP
GPIO SSO 0pF VDDP
GPIO SME 0pF VDDP
GPIO SSH 0pF VDDP
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 153: GPIO various driver settings at no load –
conducted emission on VDDP
The emission amplitudes are mainly determined by the switching ports activity if any strong driver
setting is used. For weak and medium driver settings the port emission stays below the system clock
emission and is not visible in the envelope curves.
Application Note AP16099
112
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Fig. 154 compares the emission on VDDP for all possible driver settings at 22pF load.
dBµV
GPIO with 22pF Load / Crosstalk to VDDP
"Driver Setting Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
GPIO WEA 22pF VDDP
GPIO MED 22pF VDDP
GPIO SSO 22pF VDDP
GPIO SME 22pF VDDP
GPIO SSH 22pF VDDP
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 154: GPIO various driver settings at 22pF load –
conducted emission on VDDP
Again the emission amplitudes are mainly determined by the switching ports activity if any strong
driver setting is used. For weak and medium driver settings the port emission stays below the system
clock emission and is not visible in the envelope curves.
Application Note AP16099
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V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Fig. 155 compares the emission on VDDP for all possible driver settings at 47pF load.
dBµV
GPIO with 47pF Load / Crosstalk to VDDP
"Driver Setting Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
GPIO WEA 47pF VDDP
GPIO MED 47pF VDDP
GPIO SSO 47pF VDDP
GPIO SME 47pF VDDP
GPIO SSH 47pF VDDP
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 155: GPIO various driver settings at 47pF load –
conducted emission on VDDP
Again the emission amplitudes are mainly determined by the switching ports activity if any strong
driver setting is used. For weak and medium driver settings the port emission stays below the system
clock emission and is not visible in the envelope curves.
However, for big external loads like the 47pF we used for comparison, the emission reduction when
changing from strong-sharp to strong-medium or lower is not so efficient as for smaller loads like
22pF or smaller.
Application Note AP16099
114
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Fig. 156 compares the emission on VDDP in case of no load, 22pF load and 47pF load at “weak”
driver setting.
dBµV
GPIO "weak" / Crosstalk to VDDP
"Load Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
GPIO WEA 0pF VDDP
GPIO WEA 22pF VDDP
GPIO WEA 47pF VDDP
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 156: GPIO “weak” driver settings at various loads –
conducted emission on VDDP
Emissions in the higher frequency range are comparable. At low frequencies, the minimum load
causes maximum emission. This is due to the higher di/dt when charging/discharging of the load
starts. Please refer to chapter 2.1.3 for a physical explanation.
Application Note AP16099
115
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Fig. 157 compares the emission on VDDP in case of no load, 22pF load and 47pF load at “medium”
driver setting.
dBµV
GPIO "medium" / Crosstalk to VDDP
"Load Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
GPIO MED 0pF VDDP
GPIO MED 22pF VDDP
GPIO MED 47pF VDDP
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 157: GPIO “medium” driver settings at various loads –
conducted emission on VDDP
Emissions in the higher frequency range are comparable. At low frequencies, the minimum load
causes maximum emission. This is due to the higher di/dt when charging/discharging of the load
starts. Please refer to chapter 2.1.3 for a physical explanation.
Application Note AP16099
116
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Fig. 158 compares the emission on VDDP in case of no load, 22pF load and 47pF load at “strongsoft” driver setting.
dBµV
GPIO "strong-soft" / Crosstalk to VDDP
"Load Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
GPIO SSO 0pF VDDP
GPIO SSO 22pF VDDP
GPIO SSO 47pF VDDP
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 158: GPIO “strong-soft” driver settings at various loads –
conducted emission on VDDP
Emissions in the higher frequency range are comparable. At low frequencies, the minimum load
causes maximum emission. This is due to the higher di/dt when charging/discharging of the load
starts. Please refer to chapter 2.1.3 for a physical explanation.
Application Note AP16099
117
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Fig. 159 compares the emission on VDDP in case of no load, 22pF load and 47pF load at “strongmedium” driver setting.
dBµV
GPIO "strong-medium" / Crosstalk to VDDP
"Load Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
GPIO SME 0pF VDDP
GPIO SME 22pF VDDP
GPIO SME 47pF VDDP
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 159: GPIO “strong-medium” driver settings at various loads –
conducted emission on VDDP
Emissions in the higher frequency range are comparable. At low frequencies, the minimum load
causes maximum emission. This is due to the higher di/dt when charging/discharging of the load
starts. Please refer to chapter 2.1.3 for a physical explanation.
Application Note AP16099
118
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Fig. 160 compares the emission on VDDP in case of no load, 22pF load and 47pF load at “strongsharp” driver setting.
dBµV
GPIO "strong-sharp" / Crosstalk to VDDP
"Load Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
GPIO SSH 0pF VDDP
GPIO SSH 22pF VDDP
GPIO SSH 47pF VDDP
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 160: GPIO “strong-sharp” driver settings at various loads –
conducted emission on VDDP
Emissions in the higher frequency range are comparable. At low frequencies, the minimum load
causes maximum emission. This is due to the higher di/dt when charging/discharging of the load
starts. Please refer to chapter 2.1.3 for a physical explanation.
Application Note AP16099
119
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
6.3
Radiated emission
Above 100MHz, using “strong-medium” instead of “strong-sharp” driver for the CLKOUT pin leads to
a radiated emission reduction between 6dB and 10dB. Fig. 161 shows the corresponding envelope
curves.
dBµV
CLKOUT without Load / Radiated Emission
"Driver Setting Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
CLKOUT SME 0pF RE
CLKOUT SSH 0pF RE
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 161: CLKOUT toggling at 40MHz; various driver settings at no load –
radiated emission
Similar differences appear for bigger capacitive loads. Radiated emission stays ca. 15-20dB below
conducted emission observed at VDDP. Please compare with Fig. 151.
Application Note AP16099
120
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
If set to “strong-sharp”, the radiated emission of 16 toggling GPIO pins (toggle rate ca. 700kHz) stays
more than 15dB below the radiated emission of the 40MHz CLKOUT pin. Weaker driver settings
(“strong-medium” and below) reduce radiated emission ca. 10dB further. Fig. 162 shows the
corresponding envelope curves.
dBµV
GPIO without Load / Radiated Emission
"Driver Setting Comparison"
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
GPIO WEA 0pF RE
GPIO MED 0pF RE
GPIO SSO 0pF RE
GPIO SME 0pF RE
GPIO SSH 0pF RE
0
100
200
300
400
500
600
700
800
900
1000
Frequency/MHz
Figure 162: GPIOs toggling at ca. 700kHz; various driver settings at no load –
radiated emission
Similar differences appear for bigger capacitive loads. Radiated emission stays ca. 10-15dB below
conducted emission observed at VDDP. Please compare with Fig. 153.
Whenever using driver settings less than “strong-sharp”, the radiated emission caused by the drivers
should not cause any problems and are neglegible against the CLKOUT emission.
Application Note AP16099
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V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
7
Recommended Settings for Signal Categories
7.1
General
In the previous chapters, many detailed data was provided for the impact of driver settings and load
capacitance on the resulting rise and fall times as well as on conducted and radiated emission.
Generally, the required signal integrity determines the selection of driver strength and slew rate for a
given toggle rate and capacitive load. However, due to the simultaneous impact on electromagnetic
emission, the weakest possible driver setting which still meets the signal integrity should be chosen.
To decide for the proper pad driver settings for a signal, its electrical characteristics should be
considered. This leads to the definition of signal categories by means of clock or data transfer (AC
view) or current driving capability (DC view). According to these views, any signal can be classified
as shown in Table 5.
Signal category
Clock rate
Capacitive load
DC driving capability
System clock
20 … 40 MHz
10 … 50 pF
n/a
High-speed data line
5 … 20 MHz
10 … 50 pF
n/a
Low-speed data line
0.5 … 5 MHz
10 … 50 pF
n/a
Low-speed control line
<1 MHz
<20 pF
n/a
High-current control line
n/a
n/a
10 … 30 mA
Medium-current control line
n/a
n/a
1 … 10 mA
Low-current control line
n/a
n/a
<1 mA
Table 5: Signal categories
The following settings for pad output drivers are available, see also Table 6:
•
strong driver / sharp edge (setting 1)
•
strong driver / medium edge (setting 2)
•
strong driver / soft edge (setting 3)
•
medium driver / no edge configuration available (setting 4)
•
weak driver / no edge configuration available (setting 5)
Setting
number
Driver
configuration
Edge
configuration
Signal category
Capacitive
Load
DC
Current 1)
1
STRONG
SHARP
System clock
High
2.5 / 10 mA
2
STRONG
MEDIUM
System clock
Low
High-speed data lines
High
High-speed data lines
Low
High-current control lines
All
Low-speed data lines
All
Medium-current control lines
All
Very low-speed control lines
All
Low-current control line
All
3
4
5
STRONG
MEDIUM
WEAK
SOFT
none
none
Table 6: Recommended Output Driver Settings
Application Note AP16099
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V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Note 1): Two values are given for the DC current of GPIO pins in the format “nominal / max mA”. The
“max mA” value can only be drawn from a pin if maximal 2 other pins in the same 16-bit port group
are also driving this maximum current. This restriction is due to danger of electromigration damage.
The following parameters determine the final selection of driver settings:
7.2
•
signal performance category (AC and DC)
•
maximum temperature
•
maximum acceptable electromagnetic emission
Decision Tables and Graphs
Following the recommendations given above, the driver setting selection should be based on (1)
proper signal integrity and (2) minimal electromagnetic emission. Since electromagnetic emission
increases with stronger driver settings, the weakest driver and slew rate settings should be selected
that are able to force the rise/fall times required for the desired signal integrity.
This chapter offers decision numbers in table and graphical format for proper driver settings at
maximum clock or data rates expected to be driven. The rise/fall times occupy 1/6th of the clock
period each, see Fig. 163 on top. Alternatively, the rise/fall times occupy 1/4th of the clock period
each, see Fig. 163 on bottom.
U
90%
T/6
T
T/6
10%
t
U
90%
T/4
T
T/4
10%
t
Figure 163: Assumed rise/fall timing conditions related to signal period
Please note that all values given in this chapter are proposals for system application designers using
Infineon microcontrollers in 0.25µm CMOS technology. They are based on timing measurements
performed on center lot devices. Thus all values are subject to approx. 10% offset depending on
fabrication process variation. Additionally, pad supply voltages different from nominal conditions
impact the resulting timing. The finally selected driver setting should include this offset. It has to be
added to all numbers given in the tables and graphs.
Application Note AP16099
123
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Fig. 164 shows an example of a decision graph.
Figure 164: Assumed rise/fall timing conditions related to signal period
The clock/data rate is given in [MHz] for capacitive loads of 20, 30, 40, 50 pF and driver selections of
weak, medium, strong soft/medium/sharp. In Fig. 164, the resulting maximum data rates are marked
with red circles as 17 MHz at 20 pF load, 13 MHz at 30 pF load, 12.5 MHz at 40 pF load, and 12 MHz
at 50 pF load. If a pin is intended to toggle a 35 pF load at 15 MHz, the strong-soft setting is not
sufficient. Instead strong-medium must be selected. Strong-sharp is, of course, also capable of
driving a 35 pF load at 15 MHz, but should be avoided due to unnecessary high electromagnetic
emission.
The rise/fall times occupy 1/6th of the clock period each, see Fig. 163 on top. This relation should be
acceptable for most interface signals and protocols.
Tables 7 and 8 give an overview of the maximal toggle rates in [MHz] for all driver settings
(WEA=weak, MED=medium, SSO=strong-soft, SME=strong-medium, SSH=strong-sharp) connected
to capacitive loads of 20, 30, 40, and 50 pF. Each ambient temperature is marked by its own color.
According to the microcontroller specification or marking, one of the following maximum temperatures
should apply: 125°C, 110°C, 85°C, 70°C. The other temperatures, 25°C and -40°C, are given for
reference only.
Since the CLKOUT driver is stronger than the GPIO driver, values for both driver types are provided
in Tables 7 and 8. In Table 7, the rise/fall times are assumed to occupy 1/6th of the clock period, in
Table 8, the rise/fall times are assumed to occupy 1/4th of the clock period.
Fig. 165-192 show the values of Tables 7 and 8 in the graphical representation explained in Fig. 164,
separated by ambient temperatures and driver types. In the respective titles, “16% Edges” stands for
rise/fall times occupying 1/6th of the clock period; “25% Edges” stands for rise/fall times occupying
1/4th of the clock period.
Application Note AP16099
124
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT
150°C
GPIO
SSH
SME
SSO
MED
WEA
20
49.02
27.78
11.34
6.83
1.33
30
39.22
23.47
10.10
5.56
1.03
40
33.33
21.65
9.16
5.05
0.84
50
29.66
20.23
8.96
4.80
0.68
SSH
SME
SSO
MED
WEA
20
30.30
15.02
10.82
6.97
1.38
30
23.81
13.06
9.36
5.77
1.04
40
18.16
11.00
7.88
4.69
0.85
50
15.72
10.22
7.58
4.31
0.68
SSH
SME
SSO
MED
WEA
20
53.76
30.30
12.36
7.50
1.48
30
42.80
25.22
10.83
6.03
1.13
40
36.30
23.15
9.83
5.45
0.91
50
32.08
21.58
9.57
5.14
0.74
SSH
SME
SSO
MED
WEA
20
32.81
16.06
11.65
7.45
1.52
30
25.61
13.84
10.08
6.15
1.15
40
19.76
11.89
8.56
5.08
0.93
50
17.08
11.07
8.23
4.67
0.74
SSH
SME
SSO
MED
WEA
20
57.08
32.05
13.07
7.97
1.59
30
45.28
26.40
11.32
6.36
1.20
40
38.34
24.15
10.28
5.72
0.96
50
33.73
22.48
9.97
5.37
0.78
SSH
SME
SSO
MED
WEA
20
34.52
16.75
12.19
7.78
1.62
30
26.83
14.35
10.57
6.40
1.22
40
20.86
12.49
9.03
5.33
0.98
50
18.02
11.64
8.68
4.93
0.78
SSH
SME
SSO
MED
WEA
20
63.61
35.46
14.46
8.90
1.81
30
50.13
28.63
12.24
6.98
1.34
40
42.31
26.04
11.13
6.23
1.06
50
36.89
24.16
10.73
5.80
0.85
SSH
SME
SSO
MED
WEA
20
37.81
18.06
13.21
8.38
1.82
30
29.13
15.30
11.47
6.87
1.37
40
23.00
13.52
9.94
5.83
1.09
50
19.83
12.74
9.55
5.41
0.87
SSH
SME
SSO
MED
WEA
20
68.31
37.88
15.44
9.57
1.97
30
53.58
30.16
12.87
7.42
1.44
40
45.11
27.32
11.71
6.58
1.12
50
39.09
25.30
11.24
6.10
0.91
SSH
SME
SSO
MED
WEA
20
40.10
18.95
13.91
8.78
1.97
30
30.72
15.93
12.00
7.18
1.48
40
24.51
14.20
10.57
6.18
1.17
50
21.10
13.51
10.16
5.76
0.92
SSH
SME
SSO
MED
WEA
20
87.72
47.62
19.38
12.35
2.69
30
67.20
35.92
15.22
9.13
1.85
40
56.31
32.05
13.88
7.94
1.39
50
47.62
29.45
13.12
7.18
1.13
SSH
SME
SSO
MED
WEA
20
49.02
22.22
16.55
10.29
2.60
30
36.71
18.18
13.92
8.33
1.94
40
30.53
16.73
12.92
7.51
1.50
50
26.12
16.49
12.58
7.10
1.16
SSH
SME
SSO
MED
WEA
20
148.81
75.76
30.08
21.26
5.70
30
96.56
49.59
20.67
12.95
3.17
40
80.59
42.74
18.91
11.04
2.11
50
67.44
38.59
17.30
9.55
1.72
SSH
SME
SSO
MED
WEA
20
69.91
29.61
22.79
13.67
4.85
30
51.11
22.82
18.12
10.84
3.51
40
45.82
22.55
18.36
10.44
2.51
50
39.82
23.43
18.95
10.16
1.82
125°C
110°C
85°C
70°C
25°C
-40°C
Table 7: Maximum toggle rates [MHz] for all driver settings at loads 20 … 50 pF; 16% Edges
Application Note AP16099
125
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
CLKOUT
150°C
GPIO
SSH
SME
SSO
MED
WEA
20
73.53
41.67
17.01
10.25
2.00
30
58.82
35.21
15.15
8.33
1.54
40
50.00
32.47
13.74
7.58
1.26
50
44.48
30.34
13.44
7.20
1.02
SSH
SME
SSO
MED
WEA
20
45.45
22.52
16.23
10.46
2.07
30
35.71
19.59
14.04
8.65
1.56
40
27.23
16.50
11.82
7.04
1.27
50
23.58
15.34
11.36
6.46
1.02
SSH
SME
SSO
MED
WEA
20
80.65
45.45
18.55
11.25
2.22
30
64.20
37.83
16.24
9.04
1.69
40
54.44
34.72
14.74
8.17
1.36
50
48.11
32.37
14.35
7.72
1.10
SSH
SME
SSO
MED
WEA
20
49.21
24.08
17.47
11.18
2.28
30
38.41
20.76
15.12
9.22
1.72
40
29.63
17.83
12.84
7.61
1.39
50
25.63
16.60
12.35
7.01
1.11
SSH
SME
SSO
MED
WEA
20
85.62
48.08
19.61
11.95
2.38
30
67.93
39.60
16.98
9.53
1.80
40
57.51
36.23
15.41
8.57
1.44
50
50.59
33.72
14.96
8.06
1.16
SSH
SME
SSO
MED
WEA
20
51.78
25.13
18.28
11.66
2.43
30
40.24
21.53
15.85
9.60
1.83
40
31.29
18.74
13.55
8.00
1.48
50
27.03
17.46
13.02
7.39
1.18
SSH
SME
SSO
MED
WEA
20
95.42
53.19
21.69
13.35
2.71
30
75.20
42.95
18.36
10.48
2.01
40
63.46
39.06
16.69
9.34
1.58
50
55.34
36.24
16.10
8.70
1.28
SSH
SME
SSO
MED
WEA
20
56.72
27.09
19.82
12.57
2.74
30
43.70
22.95
17.21
10.30
2.06
40
34.50
20.27
14.91
8.75
1.64
50
29.74
19.11
14.33
8.12
1.30
SSH
SME
SSO
MED
WEA
20
102.46
56.82
23.16
14.35
2.95
30
80.37
45.24
19.31
11.14
2.16
40
67.67
40.98
17.56
9.87
1.68
50
58.64
37.94
16.86
9.14
1.36
SSH
SME
SSO
MED
WEA
20
60.15
28.42
20.87
13.18
2.96
30
46.08
23.90
18.00
10.78
2.22
40
36.77
21.30
15.86
9.26
1.76
50
31.65
20.26
15.24
8.63
1.39
SSH
SME
SSO
MED
WEA
20
30
131.58 100.81
71.43 53.88
29.07 22.83
18.52 13.70
4.03
2.78
40
84.46
48.08
20.82
11.90
2.08
50
71.43
44.17
19.69
10.78
1.69
SSH
SME
SSO
MED
WEA
20
73.53
33.33
24.83
15.43
3.91
30
55.07
27.26
20.89
12.50
2.91
40
45.79
25.10
19.38
11.26
2.25
50
39.18
24.73
18.87
10.65
1.74
SSH
SME
SSO
MED
WEA
20
30
40
50
223.21 144.84 120.89 101.17
113.64 74.39 64.10 57.89
45.13 31.00 28.37 25.96
31.89 19.43 16.57 14.33
8.55
4.76
3.17
2.58
SSH
SME
SSO
MED
WEA
20
104.87
44.42
34.18
20.50
7.28
30
76.67
34.23
27.18
16.26
5.26
40
68.73
33.82
27.54
15.66
3.77
50
59.73
35.15
28.43
15.24
2.73
125°C
110°C
85°C
70°C
25°C
-40°C
Table 8: Maximum toggle rates [MHz] for all driver settings at loads 20..50pF; 25% edges
Application Note AP16099
126
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits CLKOUT at 150°C with 16% Edges
50
45
Frequency [MHz]
40
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 165: Driver selection decision graph for CLKOUT at TA=150°C; edges occupy 1/6 period
Frequency Limits CLKOUT at 150°C with 25% Edges
80
70
Frequency [MHz]
60
70.00-80.00
60.00-70.00
50.00-60.00
40.00-50.00
30.00-40.00
20.00-30.00
10.00-20.00
0.00-10.00
50
40
30
20
10
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 166: Driver selection decision graph for CLKOUT at TA=150°C; edges occupy 1/4 period
Application Note AP16099
127
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits CLKOUT at 125°C with 16% Edges
60
55
50
55.00-60.00
50.00-55.00
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
Frequency [MHz]
45
40
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 167: Driver selection decision graph for CLKOUT at TA=125°C; edges occupy 1/6 period
Frequency Limits CLKOUT at 125°C with 25% Edges
90
80
Frequency [MHz]
70
80.00-90.00
70.00-80.00
60.00-70.00
50.00-60.00
40.00-50.00
30.00-40.00
20.00-30.00
10.00-20.00
0.00-10.00
60
50
40
30
20
10
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 168: Driver selection decision graph for CLKOUT at TA=125°C; edges occupy 1/4 period
Application Note AP16099
128
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits CLKOUT at 110°C with 16% Edges
60
55
50
55.00-60.00
50.00-55.00
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
Frequency [MHz]
45
40
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 169: Driver selection decision graph for CLKOUT at TA=110°C; edges occupy 1/6 period
Frequency Limits CLKOUT at 110°C with 25% Edges
90
80
Frequency [MHz]
70
80.00-90.00
70.00-80.00
60.00-70.00
50.00-60.00
40.00-50.00
30.00-40.00
20.00-30.00
10.00-20.00
0.00-10.00
60
50
40
30
20
10
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 170: Driver selection decision graph for CLKOUT at TA=110°C; edges occupy 1/4 period
Application Note AP16099
129
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits CLKOUT at 85°C with 16% Edges
60
55
50
55.00-60.00
50.00-55.00
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
Frequency [MHz]
45
40
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 171: Driver selection decision graph for CLKOUT at TA=85°C; edges occupy 1/6 period
Frequency Limits CLKOUT at 85°C with 25% Edges
100
90
Frequency [MHz]
80
90.00-100.00
80.00-90.00
70.00-80.00
60.00-70.00
50.00-60.00
40.00-50.00
30.00-40.00
20.00-30.00
10.00-20.00
0.00-10.00
70
60
50
40
30
20
10
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 172: Driver selection decision graph for CLKOUT at TA=85°C; edges occupy 1/4 period
Application Note AP16099
130
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency [MHz]
Frequency Limits CLKOUT at 70°C with 16% Edges
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
65.00-70.00
60.00-65.00
55.00-60.00
50.00-55.00
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 173: Driver selection decision graph for CLKOUT at TA=70°C; edges occupy 1/6 period
Frequency Limits CLKOUT at 70°C with 25% Edges
110
100
Frequency [MHz]
90
100.00-110.00
90.00-100.00
80.00-90.00
70.00-80.00
60.00-70.00
50.00-60.00
40.00-50.00
30.00-40.00
20.00-30.00
10.00-20.00
0.00-10.00
80
70
60
50
40
30
20
10
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 174: Driver selection decision graph for CLKOUT at TA=70°C; edges occupy 1/4 period
Application Note AP16099
131
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits CLKOUT at 25°C with 16% Edges
90
80
Frequency [MHz]
70
80.00-90.00
70.00-80.00
60.00-70.00
50.00-60.00
40.00-50.00
30.00-40.00
20.00-30.00
10.00-20.00
0.00-10.00
60
50
40
30
20
10
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 175: Driver selection decision graph for CLKOUT at TA=25°C; edges occupy 1/6 period
Frequency [MHz]
Frequency Limits CLKOUT at 25°C with 25% Edges
140
130
120
110
100
90
80
70
60
50
40
30
20
10
0
130.00-140.00
120.00-130.00
110.00-120.00
100.00-110.00
90.00-100.00
80.00-90.00
70.00-80.00
60.00-70.00
50.00-60.00
40.00-50.00
30.00-40.00
20.00-30.00
10.00-20.00
0.00-10.00
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 176: Driver selection decision graph for CLKOUT at TA=25°C; edges occupy 1/4 period
Application Note AP16099
132
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency [MHz]
Frequency Limits CLKOUT at -40°C with 16% Edges
150
140
130
120
110
100
90
80
70
60
50
40
30
20
10
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
140.00-150.00
130.00-140.00
120.00-130.00
110.00-120.00
100.00-110.00
90.00-100.00
80.00-90.00
70.00-80.00
60.00-70.00
50.00-60.00
40.00-50.00
30.00-40.00
20.00-30.00
10.00-20.00
0.00-10.00
Cload [pF]
20
Figure 177: Driver selection decision graph for CLKOUT at TA=-40°C; edges occupy 1/6 period
Frequency Limits CLKOUT at -40°C with 25% Edges
240
220
200
220.00-240.00
200.00-220.00
180.00-200.00
160.00-180.00
140.00-160.00
120.00-140.00
100.00-120.00
80.00-100.00
60.00-80.00
40.00-60.00
20.00-40.00
0.00-20.00
Frequency [MHz]
180
160
140
120
100
80
60
40
20
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 178: Driver selection decision graph for CLKOUT at TA=-40°C; edges occupy 1/4 period
Application Note AP16099
133
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits GPIO at 150°C with 16% Edges
35
Frequency [MHz]
30
25
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 179: Driver selection decision graph for GPIO at TA=150°C; edges occupy 1/6 period
Frequency Limits GPIO at 150°C with 25% Edges
50
45
Frequency [MHz]
40
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 180: Driver selection decision graph for GPIO at TA=150°C; edges occupy 1/4 period
Application Note AP16099
134
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits GPIO at 125°C with 16% Edges
40
35
Frequency [MHz]
30
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 181: Driver selection decision graph for GPIO at TA=125°C; edges occupy 1/6 period
Frequency Limits GPIO at 125°C with 25% Edges
50
45
Frequency [MHz]
40
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 182: Driver selection decision graph for GPIO at TA=125°C; edges occupy 1/4 period
Application Note AP16099
135
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits GPIO at 110°C with 16% Edges
40
35
Frequency [MHz]
30
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 183: Driver selection decision graph for GPIO at TA=110°C; edges occupy 1/6 period
Frequency Limits GPIO at 110°C with 25% Edges
55
50
Frequency [MHz]
45
50.00-55.00
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
40
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 184: Driver selection decision graph for GPIO at TA=110°C; edges occupy 1/4 period
Application Note AP16099
136
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits GPIO at 85°C with 16% Edges
40
35
Frequency [MHz]
30
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 185: Driver selection decision graph for GPIO at TA=85°C; edges occupy 1/6 period
Frequency Limits GPIO at 85°C with 25% Edges
60
55
50
55.00-60.00
50.00-55.00
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
Frequency [MHz]
45
40
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 186: Driver selection decision graph for GPIO at TA=85°C; edges occupy 1/4 period
Application Note AP16099
137
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits GPIO at 70°C with 16% Edges
40
35
Frequency [MHz]
30
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 187: Driver selection decision graph for GPIO at TA=70°C; edges occupy 1/6 period
Frequency Limits GPIO at 70°C with 25% Edges
60
55
50
55.00-60.00
50.00-55.00
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
Frequency [MHz]
45
40
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 188: Driver selection decision graph for GPIO at TA=70°C; edges occupy 1/4 period
Application Note AP16099
138
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency Limits GPIO at 25°C with 16% Edges
50
45
Frequency [MHz]
40
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 189: Driver selection decision graph for GPIO at TA=25°C; edges occupy 1/6 period
Frequency [MHz]
Frequency Limits GPIO at 25°C with 25% Edges
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
70.00-75.00
65.00-70.00
60.00-65.00
55.00-60.00
50.00-55.00
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
Cload [pF]
20
Figure 190: Driver selection decision graph for GPIO at TA=25°C; edges occupy 1/4 period
Application Note AP16099
139
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
Frequency [MHz]
Frequency Limits GPIO at -40°C with 16% Edges
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
65.00-70.00
60.00-65.00
55.00-60.00
50.00-55.00
45.00-50.00
40.00-45.00
35.00-40.00
30.00-35.00
25.00-30.00
20.00-25.00
15.00-20.00
10.00-15.00
5.00-10.00
0.00-5.00
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 191: Driver selection decision graph for GPIO at TA=-40°C; edges occupy 1/6 period
Frequency Limits GPIO at -40°C with 25% Edges
120
110
100
110.00-120.00
100.00-110.00
90.00-100.00
80.00-90.00
70.00-80.00
60.00-70.00
50.00-60.00
40.00-50.00
30.00-40.00
20.00-30.00
10.00-20.00
0.00-10.00
Frequency [MHz]
90
80
70
60
50
40
30
20
10
0
SSH
50
SME
Driver
SSO
40
MED
WEA
30
Cload [pF]
20
Figure 192: Driver selection decision graph for GPIO at TA=-40°C; edges occupy 1/4 period
Application Note AP16099
140
V1.1, 2006-09
AP16099
Scalable Output Drivers of XC166 Family
8
Glossary
CLKOUT System Clock Output
Strong output driver for the system clock.
Cload
Ideal capacitive load connected to an output driver.
Load Capacitor
di/dt
Dynamic current over time
EMC
Electromagnetic Compatibility
The ability of an electrical device to
function satisfactorily in its electromagnetic
environment (“Immunity”) without having an
impermissible effect on its environment (“Emission”).
EME
Electromagnetic Emission
Æ EMC
GND
Ground
Ground reference of the power supply.
GPIO
General Purpose Input/Output
Standard output driver with no special electric
specification.
PI
Power Integrity
Good PI means a clean power supply system which
is not polluted by switching noise.
SI
Signal Integrity
Good SI means proper signal waveform to fulfill the
required data communication.
TA
Ambient Temperature
Temperature in the direct environment of the IC.
VDD
Power supply voltage in general.
VDDC
Core supply voltage = 2.5V nominal.
VDDP
Pad supply voltage = 5.0V nominal.
VSS
Æ GND
Application Note AP16099
141
V1.1, 2006-09
http://www.infineon.com
Published by Infineon Technologies AG