MLCC Mounting Structure for Board Deflection Crack Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional mounting structures of two-terminal electronic components like multilayer ceramic capacitors are prone to cracks due to board deflection, particularly at the boundary between external electrodes and the component body.
Innovation Solution
A mounting structure where the electronic component is connected to lands on a board via solder, with specific dimensions and gap configurations between the lands and external electrodes, ensuring that the ratio (c×e)/Gap falls within the range 3.4 to 258.8, thereby reducing stress and preventing crack generation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional soldering mounting structure is used, then electronic component can be mounted on board, but cracks occur in component body at boundary between external electrode and multilayer body due to board deflection
Solution Approach 1:
The patent applies parameter changes by optimizing the gap dimension between land and external electrode within a specific range (0.05mm to 0.5mm) and controlling the ratio (c×e)/Gap between 3.4 and 258.8. This dimensional parameter optimization reduces stress concentration at the external electrode boundary, preventing crack generation while maintaining reliable electrical connection through solder.
Solution Approach 2:
The patent applies local quality by creating a specific gap region between the land and external electrode that differs in dimensional characteristics from conventional designs. This localized dimensional modification at the critical stress area (boundary between external electrode and component body) provides stress relief exactly where needed, without affecting other parts of the component structure.
2Strength
If gap between land and external electrode is increased, then stress concentration is reduced, but solder connection area is decreased
Solution Approach 1:
The patent resolves this contradiction through parameter optimization by defining the gap within a specific range (0.05mm to 0.5mm) and controlling the ratio (c×e)/Gap between 3.4 and 258.8. This optimized gap dimension is sufficient to reduce stress concentration and prevent cracks, while remaining small enough to preserve adequate solder connection area for reliable electrical bonding.
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 proposed mounting structure effectively reduces or prevents the generation of cracks in electronic components during board deflection, ensuring reliable performance and longevity.
Implementation Method 1
solder on each of the lands, and a component main body including a pair of external electrodes on both end portions of the component main body in a length direction, each of the pair of external electrodes being connected to a corresponding one of the pair of lands via the solder
Data Source
AI summary
A mounting structure of an electronic component includes a multilayer ceramic capacitor including lands on a board and spaced apart from each other, solder on the lands, and a component main body including external electrodes on both end portions of the component main body in a length direction, each of the pair of external electrodes being connected to a corresponding one of the pair of lands via the solder. When a separation direction of the lands is an X direction and a direction orthogonal or substantially orthogonal to the X direction is a Y direction, when a width dimension of the land along the Y direction is c, a dimension of each of the external electrodes in the X direction is e, and a gap between the land and the external electrode is Gap, 3.4<(c×e)/Gap<258.8 is satisfied.