Rarely Asked Question Page

About The Author
James Bryant ,

What is the most common problem with precision analog circuits?

Probably grounding errors, but there are a number of frequently seen mistakes. They are mostly sins of omission; engineers are not perfect and can forget things.

All these issues, and more, have been discussed in earlier columns. Read them all, and pin up this list where you can read it every day!

1 RTFDS = "Read The Friendly Data Sheet."

For More Information

Analog Dialogue:

A Dozen Ways to Make a Circuit Fail
The Contaminator of Signals: HF Common-Mode-Generated Errors
Avoid Common Problems When Designing Amplifier Circuits (pdf)
Power Supply Management–Principles, Problems, and Parts (pdf)
ADC Input Noise: The Good, The Bad, and The Ugly. Is No Noise Good Noise? (pdf)
A Practical Guide to High-Speed Printed-Circuit-Board Layout (pdf)
Practical Techniques to Avoid Instability Due to Capacitive Loading
(Ask the Applications Engineer-32)
Avoiding Op-Amp Instability Problems in Single-Supply Applications (pdf)

Application Notes:

AN-1120: Noise Sources in Low Dropout (LDO) Regulators (pdf)
AN-345: Grounding for Low-and-High-Frequency Circuits (pdf)


Do Something with that Unused Pin!
Considerations on High-Speed Converter PCB Design, Part 4: Plane Coupling
Considerations on High-Speed Converter PCB Design, Part 3: The E-Pad Low Down
Considerations on High-Speed Converter PCB Design, Part 2: Using Power and Ground Planes to Your Advantage
Considerations on High-Speed Converter PCB Design, Part 1: Power and Ground Planes
Taming A/D Converter Power Supplies
Bring on the Converter Noise!
Lock Down That Noise - Don't Let It Escape
Op-Amp Noise can be Deafening Too
Igor, pass me some supply sequencers!
Grounding Converters (or Philosophy to the Rescue!)
Caveat Emptor

Technical Documentation:

Analog-Digital Conversion - Chapter 9: Hardware Design Techniques
High Speed System Applications - Section 4: PC Board Layout and Design Tools (pdf)

  • About The Author
  • James Bryant

James Bryant holds a degree in Physics and Philosophy from the University of Leeds. He is also C.Eng., Eur. Eng., MIEE, and an FBIS.