摘 要 台灣約有十萬人有聽力上的障礙,由於半導體技術及微機電技術之進步,矽晶麥克風與讀出電路已可成熟地製作於同一晶片上,最典型之應用為助聽器輔具、多媒體電腦或手機等產品。因此,發展低功率微型麥克風讀出電路日趨重要。 本文針對商用電容式矽晶麥克風,設計及實現一訊號讀出放大電路系統,整體設計流程從原理了解與文獻參考比較、電路設計、軟體模擬修正、晶片設計、實體佈局與下線及晶片量測結果,在本論文中均有詳述。 在系統效能方面,實驗結果顯示此一訊號讀出放大電路,使用台灣積體電路公司0.35慆 CMOS製程完成晶片設計製作。輸出電壓範圍大約在正負電壓源範圍,功率消耗約0.7mW,而驅動電流達212uA。讀出電路之放大倍率於50-120dB、20Hz至20kHz之不同音波頻率範圍均可正常操作,可涵蓋輕、中、重度聽障患者之聽力損失。
Hearing loss affects 100 thousands of people in the Taiwan. The MEMS is a popular technology allowing the integration of silicon microphone and its interface electronics, such as hearing aid device. Thus, to implement a low power microphone readout circuit is an important work. In this study, a readout amplifier system design for capacitive silicon microphone applications was presented. The readout amplifier system was fabricated in a 0.35慆 CMOS technology. The operational amplifier in microphone readout circuit provides rail-to-rail output swing. The maximum supply current is 212 嫀 with 0.7mW power dissipation. Experiment results show that the proposed system has an operating response between 20Hz to 20 kHz sound wave, 50-120dB voltage gain range. The measured results proved to be suitable for use in different class of hearing loss.