Electromagnetic Compatibility (EMC) Flashcards
!!! Describe electromagnetic compatibility
The ability of a system or equipment to function satisfactory in its electromagnetic environment without introducing intolerable electromagnetic disturbances to anything in that environment.
What is immunity vs emissions?
Emissions is the energy that your device spews out.
Immunity is your devices ability to withstand external energy.
what is immunity vs susceptibility?
Immunity - degree to which a device RESISTS external energy
Susceptibility - degree to which a device is MESSED UP by external energy
What are the key components of source/path/receptor model?
1) Source
2) Receptor
3) Path
4) Radiative coupling
5) Conductive coupling
6) Emissions
7) Immunity/Susceptibility
What is intentional vs unintentional radiators?
Intentional – things that are SUPPOSED TO RADIATE energy
Unintentional – things that are NOT SUPPOSED TO RADIATE but do as a side-effect
What is unintended radiation?
Electromagnetic Pollution
What is inductive / capacitive, the source or receptor?
source –> inductive
receptor –> capacitive
What are the 4 types of TRANSFORMING PATHS
1) Conducted
2) Radiated
3) Conducted(then radiating from cable)
4) Radiated (then picked up by cable and conducted)
What emc compliance standards do these countries adhere to? US, Canada, EU, Japan, Australia/New Zealand
US - Federal Communications Commission (FCC)
Canada - Standards from Industry Canada (IC)
EU - Declaration of Conformity (CISPR)
Japan - need VCCI marking
AU/NZ - ACA registration
What is a class A vs class B device
Class A - marketed for use in commercial, industrial or business environments
Class B - marketed for use in residential environments
What is FCC?
US Federal Communications Commission
What is IC?
Industry Canada
What is IEC?
International Electrotechnical Comission
What is CISPR and what is it’s function?
Comité International Spécial des Perturbations Radioélectriques.
It’s the analog standard for EU.
What is ITE?
Information Technology Equipment
What is DUT?
Device under test
What is EUT?
Equipment under test
What is OATS?
Open Area Test Site
What is insertion loss? What are the 3 major types?
The lost of signal power when a device is introduced into the transmission line. Measured in decibels.
1) Reflected losses
2) Dialectic losses
3) Copper losses
What is the configuration of a series resonant circuit?
A resistor, capacitor, and inductor in series.
What is the configuration of a parallel resonant circuit?
A resistor, capacitor, and inductor in parallel.
What is parasitic capacitance?
Typically unwanted capacitance between parts of an electronic component or circuit due to their proximity to each other.
At low frequencies, it can typically be ignored, but at higher frequencies, it can cause major problems.
What documentation do you have to provide in order to get EMC approved?
1) frequencies of all oscillators and crystals
2) schematics and pcb layouts
3) connection diagrams
4) operating modes
5) product configurations
6) power supply data
