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www.cst.com | CST workshop series 2010 | February 10 | 1
Virtual ESD Testing
www.cst.com | CST workshop series 2010 | February 10 | 2
Introduction to ESD
Definition
Testing Standards and Scenarios
Reliability of Measurments
Properties and Interpretation of ESD Simulations
Example ESD Simulations
Modelling the Gun for ESD Simualtions
Virtual Testing on a Laptop
ESD Strike to an USB Jack
Agenda
www.cst.com | CST workshop series 2010 | February 10 | 3
Electrostatic discharge (ESD) is the sudden and
momentary electric current that flows between two
objects at different electrical potentials caused by
direct contact or induced by an electrostatic field.
ESD Definition
www.cst.com | CST workshop series 2010 | February 10 | 4
ESD Damage
Catastrophic Failure
Burn Out
Breakdown of insulator
Latent Defect
Decrease of lifetime
Software Failure
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Testing Standards The IEC61000-4-2 standard defines standard test conditions that electronic
equipment should withstand. It assumes that the user will take no
precautions to prevent any ESD damage, and it defines a variety of levels
that the equipment should withstand.
The typical curve for an electrostatic discharge defined by IEC61000-4-2 has
a rise time of about 1 ns and a peak current level of around 30A.
www.cst.com | CST workshop series 2010 | February 10 | 6
Failure levels are defined by means of the max. current
Level Nominal
Voltage
[kV]
Peak Voltage
Current of Discharge
10%
[A]
Rise Time tr
With discharge switch
Current( 30%)
At 30ns At 60ns
[A] [A]
1 2 7.5 0.7 to 1 4 2
2 4 15 0.7 to 1 9 4
3 6 22.5 0.7 to 1 12 6
4 8 30 0.7 to 1 16 8
Testing Standards
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Even for guns obeying the IEC standard, failure levels for the
same device may vary from gun to gun !
Reliability of Measurments
„Correlation Between EUT Failure Levels and ESD Generator Parameters“, Jayong Koo et. al.
IEEE Trans Elect. Comp. Vol. 50 No.4, Nov 2008
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Reliability of Measurments
Even for the same gun, the orientation of the gun has a strong impact
„Correlation Between EUT Failure Levels and ESD Generator Parameters“, Jayong Koo et.
al. IEEE Trans Elect. Comp. Vol. 50 No.4, Nov 2008
Not only the discharge current, but also
the field distribution is relevant!
www.cst.com | CST workshop series 2010 | February 10 | 10
ESD Simulations
CST MWS Transient Solver is the best choice:
ESD event exhibits transient characteristics
3D Simulation is necessary -> field coupling
Complete system: PCB + housing
True Transient Co-Simulation: 1 excitation port
including all lumped elements
GPU acceleration
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Interpretation of Simulation Results
Look for large field values / large currents
Compare different positions
(w & w/o failure)
Check critical lines: CLK
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ESD Simulation of a PCB
www.cst.com | CST workshop series 2010 | February 10 | 13
Surface Current on a PCB
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Surface Current on a Mobile Phone
www.cst.com | CST workshop series 2010 | February 10 | 15
Surface Current on a Mobile Phone
High currents
at the antenna
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Gun Models
„Numerical Prediction and Measurment of ESD Radiated Fields by Free-Space Field Sensors“ S.Caniggia, F. Maradei,
IEEE Trans Elec Comp. Vol 49 No.3, Aug 2007
www.cst.com | CST workshop series 2010 | February 10 | 17
Gun Models
„Full Wave Model for simulating a Noiseken
ESD Generator“, Dazhao Liu; Nandy, A.;
Pommerenke, D.; Soon Jae Kwon; Ki Hyuk
Kim; IEEE Symposium on Electromagnetic
Compatibility,17-21 Aug. 2009
www.cst.com | CST workshop series 2010 | February 10 | 18
Gun Valiation
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Gun Validation
„Full Wave Model for simulating a Noiseken ESD Generator“, Dazhao Liu;
Nandy, A.; Pommerenke, D.; Soon Jae Kwon; Ki Hyuk Kim; IEEE Symposium
on Electromagnetic Compatibility,17-21 Aug. 2009
Discharge current
at gun tip
Induced voltage in
semi-circular loop
