High-Frequency Package With Protruding Signal Lead
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional high-frequency packages experience significant loss due to inductive effects caused by molding compounds and long bonding wires, degrading performance in high-frequency operations.
Innovation Solution
The design of a high-frequency package with a ground lead and a signal lead forming a transmission line, where protrusions on the signal lead create capacitance to compensate inductive effects, and a notched die pad aligns the die surface with lead surfaces to shorten bonding wires, reducing inductance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional wire bonding is performed to connect die with leads, then electrical connection is achieved, but inductive effect is caused leading to significant high-frequency loss
Solution Approach 1:
The lead structure is segmented into multiple sections including a body portion and an extended portion, allowing optimization of each segment for different functions. The extended portion specifically addresses high-frequency performance while the body portion maintains mechanical connection.
Solution Approach 2:
The lead structure extends in an additional dimension beyond the traditional planar configuration. The extended portion protrudes from the lead body, creating a three-dimensional structure that reduces inductance by changing the current path geometry.
2Ease of manufacture
If die surface is not coplanar with lead surfaces, then bonding is simplified, but bonding wires must be sufficiently long causing significant inductive effect
Solution Approach 1:
The lead structure is pre-configured with an extended portion that protrudes toward the die surface before bonding occurs. This preliminary configuration allows for shorter bonding wires by reducing the vertical distance the wires must span, thereby reducing inductance before the bonding process even begins.
3Reliability
If molding compound is used to cover bonding wires and leads, then package protection is achieved, but inductive effect is unavoidable causing serious loss at high frequencies
Solution Approach 1:
The lead structure has different sections with different properties optimized for different functions. The extended portion has specific dimensional characteristics optimized for reducing inductance in the high-frequency signal path, while other portions maintain mechanical and protective functions.
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
This design enhances high-frequency performance by reducing inductive losses, improving the characteristic frequency from 26 GHz to 38 GHz and minimizing frequency response ripples, thereby improving the package's operational efficiency.
Implementation Method 1
the at least a protrusion forms capacitance of the transmission line
Data Source
AI summary
A high-frequency package comprises a ground lead occupying a side of the high-frequency package; and a signal lead comprising at least a protrusion protruding from a central portion of the signal lead; wherein the ground lead and the signal lead perform as a transmission line, and the at least a protrusion forms capacitance of the transmission line.