Molded Capacitor Group Layout for Compact Circuit Boards

Solution Overview

Problem

Conventional semiconductor chip packages face challenges in power supply noise and capacitor placement, leading to constraints on package substrate design and size due to the need for minimum spacing between decoupling capacitors, which limits the number of components that can be mounted and the flexibility in routing conductor traces.

Innovation Solution

The use of molded passive component groups, where capacitors are encapsulated in a molding material to allow for tighter spacing and increased packing density, enabling more components to be mounted on a given size substrate or outside memory interface areas, thereby reducing the constraints on substrate design and size.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If decoupling capacitors are mounted individually on the carrier substrate, then power supply noise can be addressed, but the minimum spacing between capacitors limits packing density and increases substrate size

Engineering Contradiction:

Improvepower supply noise reductionVSAvoidpacking density of capacitors

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

Multiple decoupling capacitors are merged into a single molded group structure, allowing them to be positioned in close proximity while maintaining electrical isolation. The molding material encapsulates multiple capacitors (typically 4-9 capacitors per group) and provides mechanical support, enabling high-density placement on the carrier substrate without requiring individual mounting space for each capacitor.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The molding material acts as an intermediary that simultaneously provides mechanical support, electrical isolation, and structural integrity for multiple capacitors. This intermediary structure allows capacitors to be placed closer together than would be possible with individual mounting, while still maintaining the necessary electrical separation and mechanical stability.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If more decoupling capacitors are placed on the substrate, then power supply noise is better addressed, but substrate size and design constraints increase

Engineering Contradiction:

Improvepower supply noise reductionVSAvoidsubstrate area

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

Multiple decoupling capacitors are merged into a single molded group structure, allowing them to be positioned in close proximity while maintaining electrical isolation. The molding material encapsulates multiple capacitors (typically 4-9 capacitors per group) and provides mechanical support, enabling high-density placement on the carrier substrate without requiring individual mounting space for each capacitor.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The invention transitions from two-dimensional individual capacitor placement to a three-dimensional molded group structure. By stacking capacitors vertically within the molded encapsulant and utilizing Z-axis positioning, the design achieves higher capacitor density without proportionally increasing the substrate footprint, effectively utilizing the third dimension to reduce area constraints.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Manufacturing precision

If minimum spacing is maintained between capacitors, then manufacturing reliability is improved, but the number of mountable components is reduced

Engineering Contradiction:

Improvecapacitor alignment precisionVSAvoidnumber of components

Core Design Contradiction:

Manufacturing precisionVSQuantity of substance

Solution Approach 1:

Multiple decoupling capacitors are merged into a single molded group structure, allowing them to be positioned in close proximity while maintaining electrical isolation. The molding material encapsulates multiple capacitors (typically 4-9 capacitors per group) and provides mechanical support, enabling high-density placement on the carrier substrate without requiring individual mounting space for each capacitor.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The molding process performs preliminary positioning and alignment of multiple capacitors before final mounting on the substrate. Capacitors are pre-assembled into molded groups with precise relative positioning established during the molding process, which then allows for accurate placement on the carrier substrate as complete units, maintaining manufacturing precision while increasing component density.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS11837588B2Circuit board with compact passive component arrangement

Publication Date: 2023.12.05 ADVANCED MICRO DEVICES INC

AI summary

Various circuit boards with mounted passive components and method of making the same are disclosed. In one aspect, a method of manufacturing is provided that includes at least partially encapsulating a first plurality of passive components in a molding material to create a first molded passive component group. The first molded passive component group is mounted on a surface of a circuit board. The first plurality of passive components are electrically connected to the circuit board.