LTCC微型巴伦设计

Design of a Miniature Balun Based on LTCC

摘要: 本文提出了一种基于LTCC (低温共烧陶瓷)技术的微型巴伦的设计与实现方法。此种巴伦采用Marchand型结构，运用LTCC多层三维立体集成技术，通过宽边耦合的螺旋型结构实现1/4波长耦合线，大大减小了巴伦的实际体积。随后通过带状线末端电容加载技术的改进型结构，近一步缩小了耦合线长，实现了结构的微型化。最终设计的巴伦工作频带1.5~3 GHz，具有插损小，幅度平坦性好，相位一致性高的优点，巴伦尺寸为2.5 mm × 3 mm × 1.2 mm。文章讨论了该巴伦工作原理、微型化的设计思路、三维结构，最后给出了设计的仿真和测试结果，两者一致性较好。

Abstract: A method of designing and implementing a miniature LTCC balun is proposed in this paper. This kind of balun is based on the structure of Marchand microstrip balun in order to realize the mi-niaturization. LTCC multilayer 3D technology, broadband coupling spiral stripline and loading terminal capacitors structure have been used to achieve quarter-wave coupling line to reduce the size. The operation frequency ranges from 1 GHz to 3 GHz with the advantages of low insertion loss, well amplitude balance and strong phase consistency. The dimension was only 2.5 mm × 3 mm × 1.2 mm. The operation principle, design thoughts of miniaturization and the structure of balun were discussed in this paper. At last, the results from the simulation and those from the measurement are in good agreement.