現代生醫積體電路設計著重於低功率、低雜訊、低直流偏移。在本研究中使用了TSMC 0.18um製程設計出兩個儀表放大器，第一個儀表放大器是加入了交流耦合電容將主要的直流偏移降低，並且加入了增益可調的功能。第一個儀表放大器之電路增益最高為42.3 dB，最低增益為19.3 dB，並且具備60 dB的共模拒斥比與電源供應拒斥比，其功率消耗則是1.3 mW。由於加入了交流耦合電容，所以該儀表放大器的輸入等效直流偏移只有4 uV。
第二個儀表放大器則分別加入了自動歸零與截切技術達成低雜訊與低直流偏移的目標。自動歸零技巧通常被用來消除電路的直流偏移，同時可以改善運算放大器之間的不匹配。截切技巧則通常被用來消除低頻的閃爍雜訊。使用自動歸零技巧的自動歸零儀表放大器其電路增益為40.1 dB，電路頻寬為68.8 kHz，輸入參考方均根雜訊電壓從直流積分至轉折頻率為31.8 uVrms，等效直流偏移為20 uV，消耗功率為1.3mW。使用截切技巧的儀表放大器其電路增益為40.1 dB，電路頻寬為69.1 kHz，輸入參考方均根雜訊電壓為86 uVrms，等效直流偏移為40 uV，消耗功率為1.3mW。
除此之外，我們將生醫積體電路常用的偽電阻架構與交流耦合電容應用於低功率無線收發機的基頻電路。此架構的好處在於可以增加穩定度並且降低功率消耗。基頻電路增益為39.2 dB至76.5 dB，功率消耗為100 uW。此低功率收發機的靈敏度為-73 dBm(誤碼率為10-3)。最後則是針對運算放大器的設計考量與生醫植入式應用的無線傳輸系統做較深入的探討。

The design of modern biomedical-integrated circuit emphasizes low power, low noise and low dc-offset. This research shows two instrumentation amplifiers(IA) that were fabricated TSMC 0.18um CMOS process. The first instrumentation amplifier uses ac-couple capacitors to reduce dc-offset, and has variable gain control. The highest gain of the first instrumentation amplifier is 42.3 dB, the lowest gain is 19.3 dB.This IA works with 60dB of common mode rejection ratio(CMRR) and power supply rejection ratio(PSRR), and the power consumption is 1.3 mW. Because of ac-couple capacitors, the equivalent input dc-offset of the instrumentation amplifier is only 4 uV.
The second instrumentation amplifier adopt auto-zero technique and chopper tech¬nique to achieve low noise and low dc-offset. Auto-zero technique is usually used to eliminate the dc-offset of circuit, while improving the mismatch between the op amps. Chopper technique is used to eliminate low-frequency flicker noise. The auto-zero instrumentation amplifier features a gain of 40.1 dB with 68.8 kHz band-width. The input-refer root-mean-square noise that integrated from DC to corner frequency is 31.8 uVrms. The equivalent input dc-offset is 20 uV, and the total power consumption is 1.3 mW. The chopper instrumentation amplifier features 40.1 dB with 69.1 kHz bandwidth. The input-refer root-mean-square noise is 86 uV. The equivalent input dc-offset is 40 uV, and the total power consumption is 1.3 mW.
In addition, we use pseudo-resistance structure and ac-coupling capacitors that biomedical integrated circuits commonly used as a baseband circuit of low-power wireless transceiver. The benefits of those techniques are to increase stability and reduce power consumption. The gain range of baseband circuit is from 39.2 dB to 76.5 dB, and the power consumption is 100 uW. This low-power transceiver achieves -73 dBm of sensitivity (10-3 of BER). At last, we do more in-depth discussion for the wireless transmission system of implantable biomedical applications and considera-tions of op-amp design.

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