Using Op Amps to Reduce Near-field EMI on PCBs
Automotive, industrial, medical, and many other applications use sensitive analog circuits that must perform their function while remaining immune to noise disturbances in their local environment. Many of these disturbances occur on nearby "noisy" circuits located on the same printed circuit board (PCB), while other interference can be picked up by cable interfaces that couple noise onto the PCB and its circuits. One of the best ways to reduce electromagnetic interference (EMI) on PCB designs is through intelligent use of operational amplifiers (op amps). This paper reviews sources of EMI and discusses op amp characteristics that aid in mitigating near-field EMI on sensitive PCB designs.