本論文在研究一個可應用於生醫訊號系統之三角
積分類比數位轉換器。為了達到生醫專用儀器的微小
化與可攜性，高解析度與低功率的類比數位轉換器是
必需的。因應不同生理訊號量測會有不同頻寬與不同
最低解析度的需求，在此我們設計實現一個MASH 2-2
階的多級串疊三角積分調變器。此多級串疊三角積分
調變器可針對不同的訊號量測切換二階與MASH 2-2階
架構賴符合所需的效能，並利用切換式放大器的技術
來節省整體功率消耗。本設計未來可以應用在個人健
康監控系統上，長時間連續監控身體狀況，並針對異
常發生的生理訊號變化透過儲存設備或微處理器控制
系統做有效的分析與即時監測，如此將有助於醫療人
員快速掌握健康異常的徵兆，為個人健康安全把關。

　　此三角積分調變器使用台積電0.18um 1P6M CMOS
電路技術來實現，在訊號頻寬 300Hz、超取樣率為64
倍的情形下，二階輸出SNDR可以達到66dB，MASH 2-2
輸出可以達到87dB，分別具有十位元與十四位元的解
析度。在正常操作下平均功率消耗，在二階為80uw而
MASH 2-2 階為120uw，有效達到低功率的要求。未來
配合後端數位降頻濾波器的實現，將類比與數位電路
共同整合，將得以實現一混合訊號處理三角積分類比
數位轉換器晶片。

　　The sigma-delta modulator (SDM) analog to digital converter (ADC) for biomedical signals is proposed in this paper. High resolution and low power consumption are the necessary factors of ADC in micro-size and portable biomedical instruments. For the different bandwidth and resolution requirement in different biomedical signals, the Multi-Stage Noise Shaping (MASH) 2+2 order SDM is implemented. This SDM structure can be switched between 2 orders and 2+2 order for different applications, the switch operation amplifier technology is used in this ADC for less power consumption. In the future, this ADC will be applied in personal healthcare monitoring system for long-time monitoring. The abnormal data this ADC converts would be analyzed and real-time recorded by microprocessor and storage element that can help medical treatment worker to control the indications of diseases in time and to be the personal health guard.
　　The whole chip of SDM was integrated in TSMC 0.18um 1P6M CMOS technologies. With the signal bandwidth of 300Hz and over-sampling ratio of 64, it can achieve 66dB and 87dB signal-to-noise and distortion ratio, and 10 bits and 14bits resolution between 2 orders and MASH 2+2 order. In addition, the power consumption is about 80uw in 10bits and 120uw in 14bits resolution under normal operation and it achieves the request for low power. The design will have co-ordination with digital decimation filter. Hence, the analog and digital circuits will be integrated and achieved the implementation of mixed signal chip for sigma-delta analog to digital converter used in biomedical signal systems in near future.

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