應用於溫度感測器之低電壓三角積分調變器

A Low Voltage Sigma Delta Modulator for Temperature Sensor

阮翌翔(Yi-Hsiang Juan)

指導教授 ： 黃弘一

國立臺北大學/電機資訊學院/電機工程研究所/碩士(2011年)

摘要

本論文提出一個低電壓三角積分調變器，此電路是設計在於溫度感測器中的類比數位轉換部分，藉由改善轉移函數中的pole點和zero的方式來提升訊號雜訊比和動態範圍。此外為了降低閃爍雜訊和DC直流偏移電壓對於電路的影響，所以利用了chopper的技巧來降低這些雜訊對於電路的影響。此晶片使用0.18um 1P6M製程實現，訊號頻寬為40Hz、OSR為64，量測出來的訊號雜訊比為50dB、動態範圍為54而有效位元為8.6bits，晶片面積為0.445×0.675 mm2。

關鍵字

三角積分調變器 ； 溫度感測器 ； 截切穩定技術

並列摘要

This circuit design is used to transform the analog signal of the front end of temperature sensor to digital signal. By changing the pole and zero position of the transfer function, the SNR and dynamic range can be enhanced. A low voltage sigma delta modulator with improved signal-to-noise ratio (SNR) and dynamic range is proposed in this paper. In addition, the proposed circuit uses chopper stabilization technology to reduce the DC offset and 1/f noise. The proposed modulator is designed in a 0.18μm 1P6M CMOS standard process. With a signal bandwidth of 40Hz and over-sampling ratio (OSR) of 64, the measured SNR is 50dB with a dynamic range of 54dB and the ENOB is 8.6 bits e and the core area is 0.445 × 0.675 mm2.

並列關鍵字

Sigma Delta Modulator ； Temperature Sensor ； Chopper

參考文獻

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