近年來由於壽命的增加與出生率的下降，台灣已步入高齡化社會，居家照護成為了一個重要的課題。此外，文明病的產生與慢性疾病的年齡層下降，讓居家照護儀器之市場正處於蓬勃發展的階段，此類儀器具有輕量化、便於攜帶、快速檢測卻又不失精確等特性。電化學阻抗頻譜分析法(Electrochemical Impedance Spectroscopy, EIS) 是一項常用的電化學檢測方式，本晶片採用了鎖相阻抗─數位轉換器的架構，且將其所需要的大部分訊號內建於晶片之中，量測結果則會以數位碼的型式輸出，並藉由資料截取卡傳送至筆記型電腦進行計算，以實現一完整自動量測系統。
本晶片使用台灣積體電路公司(TSMC) 0.35μm 2P4M 3.3V混合訊號製程製作而成，以48 S/B封裝，晶片總面積為1.8587×1.7966 mm2，處理訊號頻率範圍為100mHz到100kHz，全系統消耗的最大功率為11.33mW。

Due to the advances in medicine and the reduction in birth rate, Taiwan has become an aging society. Therefore, home care issue has been an important topic. The desired characteristics of home-care instrumentation includes small-sized, real-time and portable. Electrical Impedance Spectroscopy (EIS) is one of the commonly used detection methods. The proposed chip realizes a lock-in impedance-to-digital converter and a sinusoidal signal generator, and its 10-bit output codes are related to the real and imaginary parts of the measured impedance. With the aid of data acquisition (DAQ) card and a laptop, an automatic EIS measurement system is achieved.
The proposed chip was fabricated by TSMC 0.35μm 2P4M CMOS/MEMS mixed-signal process, and the chip area is 1.8587×1.7966-mm2. The frequency range of the proposed chip is from 0.1Hz to 100kHz, and the power consumption is 11.33mW with a 3.3V power supply. According to the measured results, it could measure amplitude from 0.05V to 1.65V and phase shift for 360 degrees. The maximal error for amplitude and phase shift, respectively, is "±2.2" % at 10kHz and "±1.25" %.

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