生醫感測磁珠系統暨超寬頻可變增益放大器

The Biosensor for Detecting Magnetic Beads and the Ultra Wideband VGA with Dual DC Offset Cancellation

謝丞俊(Cheng-Jiun Hsieh)

指導教授 ： 呂學士

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.10670

摘要

本論文分為兩部分，第一部分介紹生醫感測磁珠系統而第二部分介紹超寬頻可變增益放大器。

生醫感測磁珠系統主要用途是分析待測物的分子，例如HIV病毒，而此系統是利用奈米磁珠特性來取代醫療上大量使用的量測方法(ELISA)，具有可攜性、低成本和簡易使用的特性，因此可以將此系統用在據點照護(Point-of-care)來達到防疫之效。而本系統的架構為兩個陣列霍爾感測器(Hall sensor array)、喬巴差異差動放大器(Chopper DDA)及低通濾波器(LPF)。此系統在晶片內部更加了線圈以產生磁場，達到真正的Lab-on-chip。

超寬頻可變增益放大器主要是應用於超寬頻系統(UWB)，主要負責在Mixer降頻後將訊號放大到一定的量級，以利後級解調。本系統的架構為四級查理虎柏可變增益放大器(Cherry-Hooper VGA)、兩路直流偏移消除(DC offset cancellation)，輸出匹配及緩衝級(Output matching and buffer)。兩路直流偏移消除，一路是用來消除直流偏移，另一路是用來增展頻寬。而不用電感的方式，讓面積大大降低也使消耗功率下降。因此此系統具有寬頻、可調增益範圍大、低功率消耗及小面積之優點。

關鍵字

磁珠 ； 生醫 ； 可變增益放大器

並列摘要

This thesis proposes two major subjects: The biosensor for detecting magnetic beads and the ultra wideband VGA with dual DC offset cancellation.
The biosensor for detecting magnetic beads is used for detect antigen in fluid. It can detect many antigen like HIV, DNA, and H1N1 virus just if we have the same type magnetic beads. This system is using the characters of magnetic beads to replace the tradition way detection in clinic (ELISA). The advantages of this biomedical system are easy-to-use, low-cost, and mobility. The system contains: two Hall sensor arrays, Chopper DDA and LPF. Besides, this system adds the coil to generate polarization field to reach the goal of lab-on-chip.
Variable gain amplifier (VGA) plays an essential role in receivers by controlling the input signal’s magnitude and normalizing the average amplitude of the signal to a proper level. This system contains: four stages VGA, two DC offset cancellation loop, and output matching and buffer for measurement propose. One DC offset cancellation loop is used to DC offset cancel. The other loop is used to extend bandwidth without inductor picking. In that way, VGA in ultra wideband system reach the goals of wide bandwidth, low power consumption, small-area, and larger gain tuning range.

並列關鍵字

magnetic beads ； bio-sensor ； VGA

參考文獻

[2] Martin A. M. Gijs “Magnetic bead handling on-chip: new opportunities for analytical applications”

[3] Octavian Florescu, Moritz Mattmann, and Bernhard Boser “Fully integrated detection of single magnetic beads in complementary metal-oxide-semiconductor”

[4] Pierre-A. Besse, Giovanni Boero, Michel Demierre, Vincent Pott, and Radivoje Popovic “Detection of a single magnetic microbead using a miniaturized silicon Hall sensor”

[6] Octavian Florescu, Moritz Mattmann, and Bernhard Boser "Fully integrated detection of single magnetic beads in complementary metal-oxide-semiconductor"

instrumentation amplifier with 100-nV offset”