我們在TSMC 0.18μm 製程實現一個以人體為傳輸介質應用於穿戴式或植入式生理訊號感測器之超低功耗頻率鍵移發射電路，由於以人體為傳輸介質，因此傳輸路徑損耗會比空氣小許多，大幅降低對發射器前端電路之功率需求。電路中類比電路之電晶體操作在次臨界區，當資料傳輸速度為10 Mb/s時，此時操作電壓為0.7V，電路功耗為700μW，此時電路傳輸每單位資料所需之能源消耗為70 pJ/bit。 An ultra low power (ULP) multi-rate frequency shift keying (FSK) transmitter applied for wireless sensors and biomedical wearable/implantable devices is proposed. And FSK transmitter can provide immunity against of interference more better than on-off keying (OOK) transmitter. Therefore, ULP FSK transmitter should provide stable link quality and extend life time of sensors. In this project, we propose a high data rate, ultra low power and variable data rate transmitter which have data rate of over 10Mbs. The energy consumption per transmitted bit of FSK transmitter can be reduced, which results in a great improvement in energy efficiency. Owing to variable data rate of the FSK transmitter, power consumption and transmission data rate of the FSK transmitter can be trade-off for optimization under different operating conditions. An ultra-low power multi-rate FSK transmitter implemented in 0.18 μm CMOS process under a supply voltage of 1V. The measured maximum data rate of 10 Mb/s under power consumption of 700 μW. Therefore, minimum energy consumption of 70 pJ per transmitted bit can be achieved under maximum data rate of 10 Mb/s.