1. 1
HDT Italia s.r.l.
High Design Technology
Headquarters TORINO (ITALY)
Corso Trapani, 16
Tel. +390.11.746104
Fax. +390.11.748109
Alessandro Arnulfo
R&D Application Engineer
2. 2
HDT Italia s.r.l.
• Founded in 1990 with the aim to
develop and market high-
performance EDA tools
• Focused on:
– Signal Integrity (SI)
– Hardware modelling
– Design&Validation of digital systems
– EMC/EMI issues
3. 3
• Consulting & Services on :
– Signal Integrity and EMC/EMI
evaluation ( from PCB to the whole system )
– Modeling
– Specific customer needs
– Definition of design&qualification
methodologies
– Test & Measurement
– Software customization
HDT Italia s.r.l.
5. 5
HDT Italia s.r.l
PRODUCTS
• SPRINT
(Simulation Program of Response of
Integrated Network Transients)
• SIGHTS
(Standard Interface for Graphic Handling
of Transient Signals)
13. 13
PRESTO CadExtract
• Links to
– Mentor Graphics, Boardstation
– COOPER&CHYAN TECHNOLOGY, SPECCTRA
– Cadence, Allegro
– Zuken Redac, Visula
– INCASES, THEDA
– Accel, P-CAD
• Complete data extraction of
– physical layout
– electrical data
14. 14
• Powerful simulation engine (SPRINT)
• Concurrent simulation of entire systems
or selected nets
• Exhaustive checks of complex PCB in
minutes
• Validated for high-speed applications up
to 1Gbit/s
• Signal Integrity investigation
– Crosstalk Analysis
– Simultaneous Switching Noise
PRESTO Features
15. 15
PRESTO Features (cont’d)
• Automated compliance analysis
– mask&wide range of stimulus patterns
– enhanced test capabilities
• User definable enhanced Signal Integrity
analysis and report
• Time Domain Reflectometry based
modeling and simulation
• Link to measurement equipment
• Link to analog simulators
16. 16
PRESTO Features (cont’d)
• Flexible model topologies&management
– Automatic package assignment
– Multipower pin management
• What-if analysis of packages and
components
• Distributed models of ground and power
nets including planes
• Multi level modeling and simulation
– electrical
– timing
– logic
– system
17. 17
PRESTO Results70.00 80.00 100.00 120.00 140.00 160.00 180.00
TIME[nS]
-4.00V
-2.00V
0.00V
2.00V
4.00V
6.00V
8.00V
#U4_1
#IC23_4
lower and upper masks
maskviolations
Net CLK1 upper and lower masks v iolation Error f igure: 8.12
Net DAT1 upper and lower masks v iolation Error f igure: 6.01
Net ADD1 lower mask v iolation Error f igure: 0.21
Net ADD2 upper mask v iolation Error f igure: 0.11
Net ADD3 upper mask v iolation Error f igure: 0.11
Net RD no v iolation Error f igure: -
Net RDN no v iolation Error f igure: -
70.00 80.00 100.00 120.00 140.00 160.00 180.00
TIME[nS]
-4V
-2V
0V
2V
4V
6V
8V
Eye-diagramopening
Jitter
19. 19
SPRINT
Simulation Program of Response
Integrated Network Transients
• Uses DSP-based algorithm
– simulation time increases linearly with complexity
– uses fixed time step
– no convergence problems
• Very fast to handle large systems
• Efficiently handles inductors&transmission
lines
• Uses accurate, efficient behavioural models
for drivers and receivers
21. 21
PRESTO FOR EMC
I) Susceptibility
• Conducted Noise Susceptibility (CNS)
# modelling capabilities EMC models
# noise injection and propagation
# What- if analysis:
- filtering analysis (schematic)
- layout traces analysis (topology)
EMC project in Automotive field on a 2-layers
analog / digital board good comparisons with
measurements
22. 22
PRESTO FOR EMC
• Susceptibility to direct perturbations (not
already automatically inserted)
# plane-wave model
# electrical equivalent models to simulate
the perturbation effects on the PCB nets
23. 23
PRESTO FOR EMC
II) Emissions
• Conducted Emissions (CE)
# modelling capabilities EMC models
# What- if analysis
# visualize the Conducted Emissions spectrum
in the input stage of the board
EMC project in Aerospace field on a multi-layered
analog board good comparisons with
measurement
24. 24
PRESTO FOR EMC
• Radiated Emissions (RE):
EMIR (EMIssions Radiated)
Prediction of PCB radiated ElectroMagnetic
Interference (EMI) at the design state
25. 25
EMIR
• Display of PCB net radiation spectrum at user
selected distances to compare with EMC
normative.
• Uses Green Dyadic functions of actual PCB
medium
Takes into account the board cross-section in
the EM Field calculation.
26. 26
EMIR
• Interfaced with PRESTO, it uses accurate
differential mode current distribution given by
SPRINT simulator
Effects like reflections, impedance
mismatches, ground-bounce, actual
VCC/GND planes influence can be taken into
account simultaneously.
Predicts VCC/GND nets radiation
27. 27
EMIR
• Display of PCB radiation diagrams at user
selected frequencies for Localization of EMI
problems
• Near-field algorithm for H field
• Takes into account the measurement setup:
– antenna polarization
– metal floor of semi-anechoic chamber
28. 28
EmiR_Cable
• Radiation due to common mode current that
spreads along cables:
- PCB which ground plane is connected to a
cable.
- shielded coaxial cable
- twisted cable
• Use of fast 3D algorithm based on PEEC
method
30. 30
Parasitic parameters evaluation: PEEC
(Partial Elements Equivalent Circuit)
Numerical method for the circuital modelling of parasitic effects in
3D structures of conductors and dielectrics ;
Leads to an equivalent circuit reduction of the structure;
The equivalent circuit is formed only by lumped passive elements
(RLC circuit);
31. 31
PEEC METHOD
The structure is subdivided into parts:
- conductive volume cells, where conduction current flows;
- dielectric volume cells, where polarization current flows;
- dielectric/dielectric or metal/dielectric surface cells, where
electric charges are stored.
At each cell a different circuit element ( L, M, C, R) is associated
(partial elements)
Using retarded controlled generator (retarded PEEC) it is
possible to take into account the propagation delay of the signals
32. 32
PEEC METHOD: EXAMPLE OF SUBDIVISION
OF THE STRUCTURE IN SURFACE CELLS
MACROMODEL APPROACH:
a partial capacitance between each pair of cells is obtained;
they are grouped leading to a mutual capacitance between
each pair of conductors
33. 33
PEEC METHOD: OPTIMIZATION
The number of cells used for the discretization is very important to
obtain accurate results: it must be optimized;
more accurate results
possible numerical errors
longer computation times
Good trade-off: uniform discretization;
More cells
34. 34
EMISSIONS OF THE PCB WITH AN
ATTACHED CABLE
• Thevenin-like approach for the cable excitation: (PEEC)
cable
Vn=j Ltrans Isign +(C20/C10)Vsign
C10
metal floor of semi-anechoic
room
Ltrans= Lplane - Mplane/track
H
Inductive and
Capacitive
coupling
Equivalent noise voltage generator
controlled by voltage and current on the track
(coefficients depending on PEEC parameters)
35. 35
EMISSIONS OF THE PCB WITH AN
ATTACHED CABLE
The Transmission Line Theory (TLT) to calculate the current
distribution on the cable, modeled as a lossy transmission line
The Hertzian Radiating Dipoles Method to calculate the RE of the
cable
The image principle to take into account the floor of the semi-
anechoic chamber
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RE from one cable placed horizontally above the floor of the
semi-anechoic chamber;
An inductive common mode filter (choke) placed in series to
the cable;
A one-layer PCB (microstrip structure) horizontally or vertically
oriented;
An unlimited number of tracks placed in any positions:
optimized algorithm to avoid too long computation times due to
PEEC matrices inversions;
EMISSIONS OF THE PCB WITH AN
ATTACHED CABLE (cont’d)
38. 38
DESCRIPTION OF THE SETUP
1 m
3 m
1,3 m
1,2 m
cable diameter = 5mm
shielded
oscillator
39. 39
COMPARISON BETWEEN MEASURED AND
SIMULATED COMMON MODE CURRENT
0.01 0.1 1
50
40
30
20
10
0
10
20
30
40
50
Frequency in GHz
dB
40. 40
COMMON MODE CURRENT THROUGH THE
CABLE (EmiR_Cable)
0.01 0.10 1.00
-50.00
-40.00
-30.00
-20.00
-10.00
0.00
10.00
20.00
30.00
40.00
50.00
f [GHz]
dBA
41. 41
COMPARISON BETWEEN THE
MEASURED AND THE SIMULATED
RADIATED FIELD
10 100 1 10
320
10
0
10
20
30
40
50
60
70
80
Frequency in MHz
|E| [dBV/m]
42. 42
EMISSIONS OF THE PCB WITH AN
ATTACHED CABLE (EmiR_CABLE)|E| [dBV/m]
Frequency in GHz
0.00 0.01 0.10
-20
-10
0
10
20
30
40
50
60
70
80
1.0
43. 43
CONCLUSIONS ON SPRINT
• SPEED ENHANCES AND ABSENCE OF
CONVERGENCE PROBLEMS ARE OBTAINED BY
THE DWN APPROACH
• SIMULATION TIME RISES PROPORTIONALY
WITH NETWORK COMPLEXITY
• LARGE NETWORKS CAN BE SIMULATED
• MIXED-MODE (ELECTRICAL/TIMING/LOGIC)
SIMULATION IS SUPPORTED
• BTM MODELS EXTRACTED FROM TDR
MEASUREMENTS ARE SUPPORTED
• HIGH SPEED DIGITAL SYSTEMS CAN BE
SIMULATED
44. 44
CONCLUSIONS ON MODELING
• SPRINT SYNTAX IS OPEN TO IBIS STANDARD
• 4-PORTS MODELS FOR I/O TAKE INTO
ACCOUNT THE EFFECTS OF SUPPLY
DISTRIBUTION NETWORK
• CAPABILITY TO MODEL ANALOG DEVICES FOR
EMC SIMULATIONS
• CAPABILITY TO BUILD VERY ACCURATE
MODELS (S PARAMETERS BASED) FOR HIGH
SPEED DIGITAL SYSTEMS
45. 45
CONCLUSIONS ON PRESTO FOR SI
• SPEED OF THE SIMULATION
• HIGH ACCURACY OF RESULTS, GOOD
AGREEMENT WITH MEASUREMENTS
• SIMULTANEOUS SIMULATION OF ALL NETS
OF A COMPLEX PCB IS AVAILABLE
• PRESTO CAN SIMULATE SIGNAL INTEGRITY,
CROSSTALK BUT ALSO SIMULTANEOUS
SWITCHING NOISE ON VCC/GND NETS OR
PLANES
• PRESTO OFFERS FACILITIES LIKE EYE-
DIAGRAMS TO STUDY HIGH-SPEED PCBS
46. 46
CONCLUSIONS ON PRESTO FOR EMC
• PRESTO IS ABLE TO PREDICT RESULTS OF
COMPLIANCE TESTS FOR:
– RADIATED EMISSIONS
– CONDUCTED NOISE SUSCEPTIBILITY
– CONDUCTED EMISSIONS
• COMPARISONS BETWEEN SIMULATIONS
AND MEASUREMENTS IN THE CONDITIONS
REQUIRED BY EMC STANDARDS-> GOOD
AGREEMENT
47. 47
FUTURE EVOLUTIONS
• PORTING OF PRESTO ON WINDOWS-NT
• CUSTOM SOLUTIONS
• OTHER FEATURES FOR THE PREDICTION OF
RADIATED EMISSIONS
48. 48
APPLICATION OF HDT
TECHNOLOGY/PRODUCTS WITHIN
ZUKEN-REDAC ENVIRONMENT
• USE OF SPRINT AND TEMA (AND EmiR) TO
DRIVE CONSTRAINTS TO BE APPLIED TO
ZUKEN-REDAC ROUTER
• USE OF SPRINT, LIBRARIES AND SIGHTS TO
PRODUCE ON-LINE SIMULATIONS