1. © 2015 Desco Industries Inc. StaticControl.com ESD Control Experts HBM vs. CDM vs. CBE What is the difference?

2. Agenda ESD Basics Different ESD Models Applications

3. ESD Basics

4. Fig 1: ESD damage/short between Emitter/Collector regions on a device. ESD

5. What is Electrostatic Discharge (ESD)? ESD is a rapid, spontaneous transfer of electrostatic charge induced by a high electrostatic field through a spark between two bodies at different electrostatic potentials as they approach or are separated from one another. There are three different ESD models identified by the standards presently: −Charge Device Model (CDM) −Machine Model (MM) −Human Body Model (HBM). Fig 2: ESD damage to a bipolar transistor

6. Formula Q=V*C Q – Charge/Potential V – Voltage C – Capacitance

7. Mechanism of ESD generation Product 1 vs. Product 2 C 1 * V =Q 1 = Q 2 = V * C 2 C 1 * V= Q 1 ≠ Q 2 = V * C 2 No ESD Event generated ESD Event generated

8. ESD Models

9. Real-life Situation Different discharges reflect different situations Real-life discharges may differ from specified ESD models Models considered for component qualification test Important to analyze your process and define most relevant model

10. HBM – Human Body Model Best understood model to date Dominant discharge on manual operation electronic assembly Operation handling devices by hand is a must Poorly grounded charged operator touching a component is source of HBM Event Processes automation eliminates HBM Better attention to grounding eliminate HBM Better in-component protection against slow rise (2-10ns) events eliminates HBM

11. What is ESD? Charged Human Body Discharge from a fingertip to a grounded component 100 pF capacitor discharged through a switching component and 1,500 ohm series resistor into the device under test By ESDA

12. Example

13. CDM – Charge Device Model Most relevant in today’s electronic production Rapidly discharge of energy from a charged device to ground Dominant discharge on automated operation electronic assembly Voltage induction to component and tribocharging is a must Faster processes automation - problematic Very fast discharge – high energy, trace overheating – craters or blown-up traces RF high frequency components have little protection

14. CDM – What is it? Device depended CDM event has less than 2.0 nanoseconds duration Rise time of CDM event could be as short as 65 picoseconds By ESDA

15. Example

16. CBE – Charge Board Event Rapidly discharge of energy from a charged PCB to component High capacitance board (>125pF) holds much more voltage Voltage induction to the board and component becomes important Very fast discharge – high energy/high current CBE an extension of CDM Components on the board go through EOS

17. PCB potential depended – rapid discharge Higher Peak Current than CDM Event Influences component in the path of the discharge CBE – What is it? By Analog Devices

18. Detecting ESD Events in Your Production Identify component sensitivity and measure ESD events Instrumentation insures compliance Products used: −SCS EM Aware TNG ESD Event Monitor Starter Kit −SCS EM Eye Meter −SCS ESD Pro Event Indicator

19. Applications

20. Finding the Root Causes of ESD Identify the Application Where ESD Events are Being Created For Example… −SMT Line −Soldering −Printer −Repair −Functional Test (Manual or Automatic Testing) −Manual Applications Must Know Where to Look… SCS Expertise and Technology Can Help