高稳定I/F转换SiP系统集成技术研究

Research on High-Stability I/F Conversion SiP System Integration Technology

摘要: 针对惯导系统对微小加速度传感信号检测的高稳定度及小型化需求，本文研究一种I/F SiP微模组的系统集成技术。基于混合集成工艺和复合陶瓷材料体系，设计了一种包含薄膜电阻和温度补偿电阻配对架构的高精度电流频率转换电路，可将传感器输出的10⁻¹⁰~10⁻¹² A信号转换为数字信号；同时提出了一种新的LTCC + HTCC双材质多腔体一体化PiP结构，可实现电流积分、比较单元、高精度恒流源、扩流单元和开关单元等不同功能电路的异构集成和分腔布局。该方案实现了微弱加速度信号的高稳定检测，试验结果表明，该SiP正路输出稳定性可达14 ppm，负路可达25 ppm，SiP体积减小为原系统的13%，解决了惯导系统小型化、轻量化设计中的关键技术问题。所提出的集成技术方案可为同类高精度加速度传感微模组、数字化电流检测微模组等系统集成提供参考。

Abstract: To address the requirements for high stability and miniaturization in the detection of micro-acceleration sensing signals by inertial navigation systems, this study investigates an integrated system technology for an I/F SiP micro-module. Utilizing hybrid integration processes and a composite ceramic material system, a high-precision current-to-frequency conversion circuit featuring a paired architecture of thin-film resistors and temperature-compensation resistors was designed, capable of converting sensor output signals ranging from 10⁻¹⁰ to 10⁻¹² A into digital signals. Concurrently, a novel LTCC + HTCC dual-material, multi-cavity, integrated PiP structure is proposed, enabling the heterogeneous integration and compartmentalized layout of diverse functional circuits, including current integration, comparison units, high-precision constant current sources, current expansion units, and switching units. This scheme achieves highly stable detection of weak acceleration signals. Experimental results demonstrate that the output stability of the SiP reaches 14 ppm for the positive channel and 25 ppm for the negative channel, while the SiP volume is reduced to 13% of that of the original system, thereby resolving critical technical challenges in the miniaturization and lightweight design of inertial navigation systems. The proposed integrated technology provides a valuable reference for the system integration of similar high-precision acceleration sensing micro-modules and digital current detection micro-modules.