PCB Ground Cage Shields High Voltage Power Planes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Printed circuit boards (PCBs) in data storage devices face issues with high voltage ringing noise and current inrush spikes due to parasitic capacitance and inductance, leading to signal integrity problems and system malfunctions.
Innovation Solution
A multi-layer PCB structure is designed with top and bottom layers and multiple intermediate layers, including a high power plane and low power planes, with a ground cage enclosing the high power plane to block capacitive and inductive paths, minimizing noise coupling to adjacent layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If high voltage power planes are placed adjacent to signal traces and low power planes on the same PCB layers, then power delivery efficiency is improved, but noise coupling occurs due to parasitic capacitance and inductance
Solution Approach 1:
The PCB is divided into multiple layers with distinct functions: high power planes are segregated on specific layers (first and second PCB layers) away from signal traces, while intermediate layers (third and fourth PCB layers) with ground cages are inserted between power planes and signal/low power layers to block noise coupling paths
Solution Approach 2:
Ground cages are introduced as intermediary structures between the high voltage power planes and the signal traces/low power planes. These ground cages act as shields that block both capacitive and inductive noise coupling paths, allowing power planes to remain adjacent for efficient power delivery while preventing noise transmission
2Object-generated harmful factors
If ground cages are added to shield high power planes, then noise coupling is reduced, but device complexity increases
Solution Approach 1:
The ground cages are merged with the existing PCB layer structure, where the third and fourth PCB layers serve dual purposes as both structural PCB layers and noise shielding ground cages. This integration reduces the need for separate shielding components and minimizes overall device complexity while still providing effective noise blocking
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The structure effectively shields high voltage power planes, reducing noise coupling and preventing signal integrity issues, thus enhancing the reliability of data storage devices.
Implementation Method 1
capacitive and inductive paths between the high power plane and each of the first and second signal traces and capacitive and inductive paths between the high power plane and each of the first and second low power planes are blocked
Implementation Method 2
capacitive and inductive paths between the high power plane and each of the first and second signal traces and capacitive and inductive paths between the high power plane and each of the first and second low power planes are blocked
Data Source
AI summary
A printed circuit board (PCB) structure is provided for a solid state drive. In an embodiment, a solid state drive includes top and bottom layers, multiple intermediate layers and a ground cage. Each of top and bottom layers includes a plurality of components for operation of the solid state drive. The multiple intermediate layers enable electrical signals to pass between components on the top and bottom layers, one of the multiple intermediate layers including a power plane having a high voltage relative to each of the other planes. The ground cage shields signal traces on the same layer as the power plane and planes in adjacent layers from noise generated by the power plane.