ESD for Analog Circuits
This course on ESD for analog circuits has six lessons and two laboratories on simulation of ESD circuit protection. Also two lessons are included on how to use Electric for building schematics and NGSPICE for simulation.
The six lesson on ESD for analog circuits are:
- Lesson 1 – ESD models and methods
- Lesson 2 – ESD clamps
- Lesson 3 – ESD output circuit protection
- Lesson 4 – ESD input circuit protection
- Lesson 5 – Simulation of ESD clamps using a SPICE-like simulator
- Lesson 6 – ESD systems protection and tools
The two laboratories illustrate how to use ESD snapback clamp models to simulate ESD output and input protection. These labs are:
- Lesson 7 – Lab01: Simulation of ESD output protection circuits
- Lesson 8 – Lab02: Simulation of ESD input protection circuits
The two optional lessons are for those who are not familiar with using Electric and NGSPICE (and Symprobe) available using the tools provided by Efabless.
- Lesson 9 – How to use Electric
- Lesson 10 – How to use NGSPICE and Symprobe
After completing the lessons of this course the student will have the capability of designing and simulating ESD protection of analog circuits that work as predicted.
Lessons
E02 – Lesson 2 – ESD Clamps
This lesson first reviews the breakdown mechanism and characteristics of the bipolar junction transistor. This background is used to understand the regenerative process that takes place called snapback. The influence of the rise time of the ESD event and the base current on snapback are examined. Next, snapback in MOSFETs is described along with ways … Continue reading “E02 – Lesson 2 – ESD Clamps”
E03 – Lesson 3 – ESD Output Circuit Protection
This lesson shows how to design ESD protection for output circuits. The type of ESD event that is important to the output is the human body model. The goal is to protect the output transistors from over voltage any of it’s terminals and particularly the drain-source and collector-emitter. Also in this lesson the second breakdown … Continue reading “E03 – Lesson 3 – ESD Output Circuit Protection”
E04 – ESD Input Circuit Protection
This lesson focuses on protecting the gates of MOSFETs that are connected to external pins from a charge device model ESD event. The architecture of the protection scheme includes a primary and secondary ESD clamps separated by an ESD resistor. The objective of the ESD input protection scheme is to make sure that the charge … Continue reading “E04 – ESD Input Circuit Protection”
E05 – Simulation of ESD Clamps
This lesson presents a simple SPICE simulation model for ESD snapback clamps that allows the analog designer to simulate the performance of the ESD protection circuit. Up to this point, simulation of ESD snapback clamps required complex models developed by model specialists. A simple snapback model is developed for ESD clamps that are not sensitive … Continue reading “E05 – Simulation of ESD Clamps”
E06 – ESD Systems Protection and Tools
This lesson deals with the systems perspective of applying ESD protection. Rail-to-rail and local-clamp based protections schemes are discussed. The physical aspect of ESD circuits is crucial to their performance and the importance of ESD buses and cell connections for HBM and CDM protection are illustrated. Parasitic snapback transistors are discussed. This type of snapback … Continue reading “E06 – ESD Systems Protection and Tools”
E07 – Lab01 – Simulation of ESD Clamps
This laboratory will develop a SPICE simulation model for the RGNMOS, GGNMOS, and LVTSCR snapback clamps from their IV characteristics. Each clamp will be simulated to show the resulting IV characteristics of the model. The steps for performing the laboratory are given. When the student has completed the laboratory, send Dr. Allen a copy of … Continue reading “E07 – Lab01 – Simulation of ESD Clamps”
E08 – Lab02 – Simulation of ESD Protection for an Op Amp
This laboratory takes the ESD snapback clamp models from the previous laboratory to simulate the ESD protection of the input and output of a two-stage op amp with PMOS differential input transistors. The steps for performing the laboratory are given. When the student has completed the laboratory, send Dr. Allen a copy of your results … Continue reading “E08 – Lab02 – Simulation of ESD Protection for an Op Amp”
E09 – How to Use ELECTRIC
This 38 minute video reviews how to use Electric to draw a schematic which forms the netlist for simulation. This is one of the tools on the Efabless platform which you will need to use to do simulation of your circuits. There are no notes for this lesson.
E10 – How to Use SPICE and SYMPROBE
This 39 minute video reviews how to use NGSPICE and the post-processor Symprobe to do simulation and post-processing of your circuits. These tools reside on the Efabless platform and will be used to perform the laboratories. There are no notes for this lesson.