A 8.6 μW 3-bit programmable gain amplifier for multiplexed-input neural recording systems

We report a fully-integrated low-power 3-bit programmable-gain amplifier (PGA) that can be used as the second stage amplifier to adjust the gain for multi-channel neural recording systems. The design strategy maximizes energy-efficiency using a technique by optimizing a slew rate, gain and phase margin. The PGA consumes 8.66μW from 1-V single supply. This is an order of magnitude lower than the previous designs reported up to date. Analysis, simulation, and measurement results will be described in detail for a part of a multiplexed 16-channels neural recording system. In this implementation, while giving a full flexibility of gain control, the overhead for each channel is quite negligible: only 0.54μW in power and less than 0.002mm2 in area.

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