Switching Device Multi-Layer Channel Routing Parasitic Capacitance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In multi-input and multi-output (MIMO) wireless communication systems, the increase in the number of input and output terminals leads to wire intersections in metal layers, resulting in parasitic capacitance and increased insertion loss due to signal power decrease.
Innovation Solution
The switching device is designed with channels intersecting on different layers, where one channel is on the first layer and another on the third layer, with no channels on the second layer at the intersection area, minimizing parasitic capacitance and reducing signal power loss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the number of input terminals and output terminals is increased to support MIMO, then the device can simultaneously transmit and receive different data units through multiple channels, but the wires constituting the channels intersect in multiple metal layers causing parasitic capacitance and increased insertion loss
Solution Approach 1:
The patent applies dimensionality change by routing channels through different metal layers (first layer, second layer, third layer) to avoid planar intersections. Specifically, when channels must cross, one channel is routed on the first metal layer while another channel crosses on the third metal layer, utilizing the vertical dimension to eliminate harmful parasitic capacitance from lateral wire intersections.
2Length of stationary object
If wires are routed to a shared node with equal length, then the distance between the shared node and each terminal is minimized, but this configuration becomes impossible when multiple channels need to connect multiple input and output terminals simultaneously
Solution Approach 1:
The patent extends the routing space from two-dimensional planar routing to three-dimensional multi-layer routing. Channels can traverse vertically between metal layers to reach different terminals, enabling flexible connectivity configurations that would be impossible in a single plane while maintaining reasonable path lengths.
Solution Approach 2:
The patent segments the routing path into multiple layers, allowing different portions of channels to reside on different metal layers. This segmentation enables independent optimization of each channel's path and avoids the constraints of planar routing when connecting multiple terminals.
3Length of stationary object
If channels are routed on adjacent metal layers to minimize distance, then the channel length is reduced, but parasitic capacitance increases due to closer proximity between layers
Solution Approach 1:
The patent introduces an intermediary metal layer (second layer) that acts as a buffer between channels routed on the first and third layers. When channels must cross, they are separated by this intermediate layer, which reduces the electric field coupling and parasitic capacitance between the signal-carrying channels while still allowing efficient vertical transitions.
Data Source
AI summary
A switching device includes first to third layers laminated in sequence above a principal surface of a substrate, a plurality of input terminals, a plurality of output terminals, a plurality of switching circuits, and a plurality of channels. Each of the channels electrically connecting one of the plurality of input terminals and one of the plurality of output terminals with one of the plurality of switching circuits interposed therebetween. The plurality of channels include a first channel and a second channel that intersect with each other when the principal surface of the substrate is seen in a plan view. In an intersection area where the first and second channels intersect with each other, the first channel is disposed on the first layer, the second channel is disposed on the third layer, and none of the plurality of channels is disposed on the second layer.