微电子植入式脉冲发生器是20世纪中期问世的一种高科技医疗仪器。它集成了现代科技在微型制造、生物相容性材料、高性能电池、射频通信等各个学科的成果，在功能性电刺激、神经电刺激、肌电生物反馈及镇痛等领域有着广泛的应用。同时，微电子植入式脉冲发生器产品也是一个盈利丰厚且仍在快速增长的行业，有着非常广阔的市场前景。完善和优化植入式脉冲发生器的性能，提高医疗仪器的质量水平是生物医学工程和仪器科学领域的重点研究方向之一。本文的目的是研究植入式脉冲发生器中的各个关键技术，完成系统整体方案的设计，并研究保证产品质量的方法。 本文介绍了用于电流刺激疗法的植入式脉冲发生器的设计与实现；低功耗的设计方法，以及系统可靠性的研究方法。 本文对目前国内外用于电刺激疗法的微电子植入式医疗仪器进行了调研；选择了植入式神经刺激器作为主要研究对象；确定了用于电刺激疗法的微电子植入式脉冲发生器的主要参数。随后，根据神经刺激应用的需要，完成了微电子植入式脉冲发生器的硬件系统与软件系统的研究与开发。文中设计的脉冲发生器输出的脉冲电流的频率从1Hz到30Hz分档可调，电流强度从0到3.5mA分档可调，脉冲宽度从130uS到1000uS分档可调。 文中对所研究开发的脉冲发生器的功耗水平进行了优化和测试。在经过多种手段的优化之后，系统的平均功耗在一般使用情况下可以控制在20uA左右。在使用2.8V，2500mAh电池供电情况下，可以工作8年以上。 文中还对脉冲发生器的系统可靠性进行了分析和预测。不仅对系统的设计制作，以及使用过程可能出现的问题进行了研究，还在硬件、软件中进行了相应的设计。根据美军标MIL-HDBK-217F，使用元件应力分析法进行可靠性预测，系统70000小时寿命可靠性可以达到0.96。 本文所设计的脉冲发生器电路精简、集成度高、可靠性高、功耗低，输出电流精度和功耗水平都达到了国外同类产品的水平。此外，文中设计的脉冲发生器还具有参数调节更加灵活、系统固件可升级的特点。
Microelectric implantable pulse generator is a kind of high tech medical device developed in 20th century. It integrates modern technologies in many fields, such as microfabrication, biocompatible materials, high performance battery and RF communication. It is being widely used in FES, neuro-electrical stimulation, muscle electrical feedback and pain treatment. Microelectric implants have also become a fast growing market with large profit in the past few years. It’s an important task for biomedical engineering and instrument technology to improve the implantable pulse generator. The purpose of this thesis is to research the key technologies of implantable pulse generator, establish a system design, and try to enhance its quality. We've introduced the design and realization of implantable pulse generator used in electrical stimulating therapy, the method of designing a low consumption system, as well as the method of predicting system’s reliability. We’ve studied the IMD used in electrical stimulating therapy at home and abroad, and confirmed the parametres. Then the hardware and software systems are developed according to the needs of nerve stimulation. The pulse generator can output current with the frequency ranged from 1 to 30Hz, the amplitude ranged from 0 to 3.5mA, and the pulse width ranged from 130 to 1000uS. The power consumption of the pulse generator is measured and optimized here. The system’s power consumption can be restricted around 20uA in usual mode, which can work for over 8 years with a 2.8V-2500mAh battery. The reliability of the pulse generator is also analyzed and predicted. The hardware and software systems are designed with FMEA. The system’s reliability for 7000-hour life reaches 0.96 which is predicted according to MIL-HDBK-217F with component stress analysis. The implantable pulse generator system is established in simplified, highly integrated, low consumption style. Besides, there are some unique features compared with foreign products, such as the parameters adjustment and firmware update.
