The Importance of Component Placement
Optimized component placement on PCBs not only can keep things neat also improve the electrostatic discharge protection for the entire board. The obvious implication of good component placement is that it affects routing on the board. In this article, several basic guidelines are given to help you improve your routing to best protect your PCB and sensitive integrated circuits.
Mind your edge
Don’t run sensitive tracks along the edge of the board. This is particularly true for supply tracks. You want to minimize radiation from these tracks, as well as their exposure to crosstalk from other tracks, whether it’s from a noisy signal, or ESD-induced interference. Keeping your noisy tracks away from everything sensitive is good design practice, anyway.
Minimize the length of your lines
Long traces and wires both can transmit and receive unintentional emissions. To minimize line length, place all the components with lots of interconnects close to each other is an easy way. This helps you to minimize the length and the number of interconnecting lines.
Place Components in the safest place
Sometimes, design requirements keep you from using protection circuits for all of your sensitive components. When that’s the case, there are steps you can take to improve the odds for those ICs.
Keep unprotected circuits away from the traces between a TVS protection circuit and a connector input, or any other location where ESD is anticipated. This can reduce the risk of exposing the component to any current caused by rapidly changing EM fields resulting from an ESD pulse.
Sensitive components that are on a protected line should be placed closer to the center of the board. That helps to balance the parasitic inductance for the best performance of the protection circuit.