Ground and Power Planes

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There are three fundamental grounding techniques;
1. Floating Ground System: The ground plane is not returned to earth.
2. Single-Point Grounding System: A single physical point in the circuitry is designated as a ground reference point.
3. Multipoint Grounding System: The ground plane is taken to earth, effectively taking each point connected to the ground plane to earth.

Refer to MIL-HDBK-1857, GROUNDING, BONDING AND SHIELDING DESIGN PRACTICES

Minimizing RF PCB electromagnetic emissions
{Sean Mercer, Ph.D., C.Eng: www.rfdesign.com}

ANTENNAS, Frequently Asked Questions
{Virtual Technologies, Ltd. }

"...a power plane at RF will act like a patch antenna, spreading spurious signals all over the PWB."

Radiated Noise from Cables
Murata Manufacturing Co., Ltd

Capacitor Info
{Cap Layout Info-Material-Temperature-Chip Sizes}

Design Rules:
1: Stack power planes next to ground planes so they capacitively couple. Coupling the power plane to the ground plane reduces the number of by-pass capacitors required in the circuit.
2: When possible use wide traces for power and ground. Thicker traces reduce the trace impedance and allow the line to carry higher current loads.
3: Avoid placing slots in ground planes. Slots in ground planes force the current to flow around the slot, separating the return current from it signal trace. Slots may be placed at the edges of the board where signal trace aren't run.
4: Avoid Ground Loops when possible, and avoid ground loops in low-level, low-frequency circuits. A ground loop is an unwanted current loop. The current flowing in the loop generates additional noise and provides no benefit to the circuits operation.
5: Board Stack-up;

Chart of PWB External Etched Copper Current Capacity: current rating based on trace cross section in square mils, temperature rise and current in amperes.
Chart of PWB Internal Etched Copper Current Capacity: current rating based on trace cross section in square mils, temperature rise and current in amperes.
Notes on Chassis Grounding

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