A Novel Variable-Gain Micro-Power Band-Pass Auto-Zeroing CMOS Amplifier
| Autor: | Chiu-Hsien Chan, Jeff LaCoss, Jack Wills, John Choma, John J. Granacki |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Engineering
business.industry RF power amplifier Electrical engineering Fully differential amplifier Low-noise amplifier law.invention law Operational transconductance amplifier Hardware_INTEGRATEDCIRCUITS Electronic engineering Operational amplifier Instrumentation amplifier Multistage amplifier business Direct-coupled amplifier |
| Zdroj: | ISCAS |
| DOI: | 10.1109/iscas.2007.378458 |
| Popis: | A micropower, low-noise, bandpass amplifier for biomedical implants is presented. Operating at low frequency, the amplifier is fully integrated without any external passive components. Low-frequency noise and offset is reduced through the autozeroing technique. The autozeroing frequency and noise bandwidth is optimized to reduce noise folding. The design consists of a novel variable gain amplifier as the first stage, a low-Gm high-pass filter as the second stage, and a low-pass Gm-C amplifier as the last stage. Subthreshold operation is utilized in all input pair transistors to reduce power consumption, while a low-Gm OTA (operational transconductance amplifier) is realized with a current division technique. A cross-couple parallel pair of source degeneration transistors is utilized to increase the linearity crucial to neural spike detection. The design is realized in a CMOS 0.18mum process. It has an offset of 600muV, a variable gain from 42dB to 0dB, and 50 to 900Hz bandwidth while occupying 0.245mm2 area. The total circuit consumes only 26muW in a 1.8V power supply; the input referred noise is estimated to be 5.6muVrms. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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