EMI
EMI turns up in 2 fields: electrotechnology, electronics. Here is what it means to the people in each one.
EMI in electrotechnology
Electromagnetic interference: unwanted electrical noise that disturbs the operation of a circuit or system.
EMI, electromagnetic interference, is any electromagnetic disturbance that degrades performance, coupled by conduction along cables, by capacitive or inductive coupling between nearby conductors, or by radiation. Common sources are switching power supplies, motor drives, relay coils, digital clocks and radio transmitters. Cures include filtering, shielding, twisted pairs, ferrite cores and layouts with short, tight current loops.
"Every time the welder strikes, the HMI freezes, classic EMI on the comms cable, reroute it away from the welding leads."
EMI in electronics
An external memory interface connects a microcontroller or processor to off-chip memory.
External Memory Interface is a dedicated hardware bus on a chip used to communicate with external RAM, ROM, or flash memory. It handles the addressing, data lines, and control signals required to read and write data outside the main processor package. Designers use it when the on-chip memory is insufficient for the application payload.
"Route the EMI traces carefully so we don't introduce timing skew between the address and data lines."