Airtight Optical Module Connector High-Frequency Signal Routing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing BOX packaging technology for airtight optical modules faces challenges in optimizing high-frequency performance due to impedance discontinuities in the high-speed link between the optical chip and the external PCBA, and the length of gold wires being too long.
Innovation Solution
The proposed airtight optical module design includes a connector with specific surface arrangements for direct-current and high-frequency signal lines, allowing for shorter gold wire lengths and reduced impedance discontinuities by aligning the signal line surfaces on the connector and circuit board in a way that minimizes wire length and optimizes signal flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional BOX packaging structure with flexible circuit boards and gold wires is used, then the optical module achieves airtight packaging and electrical connection, but multiple impedance discontinuities occur in the high-speed link between optical chip and external PCBA, making it difficult to optimize high-frequency performance
Solution Approach 1:
The connector is divided into multiple functional layers: an upper layer surface for direct-current signal lines and a lower layer surface for high-frequency signal lines. This segmentation allows independent optimization of each signal type's transmission path, reducing impedance discontinuities by separating DC and high-frequency signal routes rather than sharing a single complex routing path.
Solution Approach 2:
The signal connection is transitioned from a planar two-dimensional routing on a single circuit board to a three-dimensional multi-layer structure. The upper layer handles DC signals while the lower layer handles high-frequency signals, adding the vertical dimension to the signal transmission architecture. This dimensional separation reduces impedance discontinuities by providing dedicated pathways for different signal types.
2Reliability
If traditional packaging structure is used, then the optical module achieves basic functionality, but the length of gold wires being large makes it difficult to be shortened to optimize high-frequency performance
Solution Approach 1:
The connector is pre-configured with dedicated connection surfaces and signal line arrangements before final assembly. The upper layer surface and lower layer surface are prepared in advance with appropriate trace patterns and connection points, allowing gold wires to be routed along optimized paths that minimize length while maintaining electrical performance.
Solution Approach 2:
The connector acts as an intermediary component between the optical chip carrier and the external circuit board. It provides structured intermediate connection points with dedicated surfaces for both DC and high-frequency signals, enabling shorter and more efficient gold wire connections compared to direct routing through traditional packaging structures.
3Speed
If BOX packaging structure is used, then the optical module achieves product miniaturization and easy heat dissipation, but multiple impedance discontinuities make it difficult to further optimize high-frequency performance in higher-speed applications
Solution Approach 1:
Different regions of the connector are designed with specialized local characteristics: the upper layer surface is optimized for DC signal transmission with appropriate trace widths and materials, while the lower layer surface is optimized for high-frequency signal transmission with controlled impedance characteristics. This local quality differentiation enables the connector to support higher data transmission speeds while maintaining high-frequency performance.
Solution Approach 2:
The connector design incorporates specific parameter optimizations including controlled trace widths, adjusted wire thicknesses, and modified material properties to achieve desired impedance characteristics. By carefully controlling these parameters in the upper and lower layer surfaces, the system can support higher speeds while maintaining signal integrity.
Data Source
AI summary
An airtight optical module, comprising: a box-shaped tube shell (10), a rear end wall (113) of which is provided with a channel groove (1130); a connector (30), which is embedded in the channel groove (1130), and has an upper layer surface (301) provided with a direct-current signal line (3D), and a lower layer surface (303) provided with a high-frequency signal line (3G), wherein the upper layer surface (301) is open upwards and comprises a first area (301a) located in front of the rear end wall (113) and a second area (301b) located behind the rear end wall (113), and the lower layer surface (303) comprises a third area (303a) which is located in front of the rear end wall (113) and is open upwards, and a fourth area (303b) which is located behind the rear end wall (113) and is open downwards; a chip carrier assembly (40), which is arranged in the tube shell (10), and comprises an optical chip (41) and a carrier (43), wherein the chip carrier assembly (40) is electrically connected to the direct-current signal line (3D) of the first area (301a) and the high-frequency signal line (3G) of the third area (303a); and a circuit board (20), the lower surface (23) of which is provided with a high-frequency signal line (3G) and is connected to a high-frequency signal line (3G) of the fourth area (303b) by means of a gold wire (53), and the upper surface (21) of which is provided with a direct-current signal line (3D) and is connected to a direct-current signal line (3D) of the second area (301b) by means of a gold wire (51). In this way, a high-frequency signal interconnection gold wire between the connector (30) and the circuit board (20) is short, thereby optimizing the high-frequency performance.