Abstract
An ultra-low power bulk-driven operational transconductance amplifier circuit for biomedical applications is presented. Higher DC gain and improved slew rate is achieved using double recycling technique, cross-coupled positive feedback configuration and driver transistors to enhance the transconductance of the conventional bulk-driven folded cascode amplifier. The post layout simulation of the proposed bulk-driven double recycling OTA in 180 nm CMOS technology, shows a 30 dB DC gain improvement and a 250% enhancement in GBW. The above results are validated using the Monte Carlo process variation and corner case simulations. The amplifier consumes 145 nW @ 0.6 V supply voltage.
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Ghaemnia, A., Hashemipour, O. An ultra-low power high gain CMOS OTA for biomedical applications. Analog Integr Circ Sig Process 99, 529–537 (2019). https://doi.org/10.1007/s10470-019-01438-6
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DOI: https://doi.org/10.1007/s10470-019-01438-6