Title :
Dynamic-range analysis and maximization of micropower Gm-C bandpass filters by adaptive biasing
Author :
Arfin, Scott K. ; Mandal, Soumyajit ; Sarpeshkar, Rahul
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Massachusetts Inst. of Technol., Cambridge, MA, USA
Abstract :
We analyze and present an input gain-varying scheme for maximizing dynamic range in a well-known Gm-C bandpass filter by both minimizing noise for small input signals, and by achieving balanced swing levels at all filter nodes for large input signals. A micropower bandpass filter suitable for use in cochlear implants and other power-constrained biomedical applications was implemented and tested in subthreshold CMOS. At a center frequency of 1.4 kHz and quality factor of 4, the filter has 70 dB of dynamic range (57 dB maximum SNR, 2.5% total harmonic distortion (THD)) and consumes 2.55 muW of power.
Keywords :
CMOS integrated circuits; band-pass filters; low-power electronics; THD; adaptive biasing; cochlear implants; dynamic-range analysis; frequency 1.4 kHz; micropower Gm-C bandpass filters; power 2.55 muW; power-constrained biomedical applications; subthreshold CMOS; total harmonic distortion; Band pass filters; Cochlear implants; Dynamic range; Frequency; Noise level; Power harmonic filters; Q factor; Signal analysis; Testing; Total harmonic distortion;
Conference_Titel :
Circuits and Systems, 2009. ISCAS 2009. IEEE International Symposium on
Conference_Location :
Taipei
Print_ISBN :
978-1-4244-3827-3
Electronic_ISBN :
978-1-4244-3828-0
DOI :
10.1109/ISCAS.2009.5118422
