کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
548003 | 872079 | 2008 | 7 صفحه PDF | دانلود رایگان |
This paper proposes a novel structure of ASK (amplitude shift keying) demodulators, which requires no external capacitors, for implantable micro-stimulators. By using a traditional ββ multiplier reference to detect the signal envelope, followed by a Schmitt trigger and a load driver, the large off-chip capacitor in traditional ASK demodulators is not required any more. Therefore, the proposed circuit possesses small area to be integrated in an SOC (system-on-chip). Besides, due to the lack of the large capacitor, the proposed circuit can operate with a higher data rate using lower frequency carriers. The proposed circuit is integrated in an implantable micro-stimulator on silicon using 0.35μm 2P4M CMOS process. The area of the proposed circuit occupies merely 0.039mm2 with a maximum power dissipation of less than 12 mW (including the power consumption of the analog circuits of the micro-stimulator) by measurement results on silicon. Moreover, the measurement results verify that the proposed ASK demodulator can detect the ASK modulated signal up to 570 kbps data rate at 2 MHz carrier frequency when the modulation index is 10%.
Journal: Microelectronics Journal - Volume 39, Issue 1, January 2008, Pages 130–136