Design of Energy-efficient Low-Noise Amplifier for Brain Computer Interface Neural Recording Applications

For invasive Brain-Computer Interface (BCI) applications, designing low-noise, low-power amplifiers is critical, particularly for intracranial electroencephalography (iEEG) signals. These signals, which use electrodes situated on or inside the brain to detect neural activity, need amplifiers that reduce noise and power consumption to record low-amplitude signals reliably. This work uses 180 nm CMOS technology to create a current reuse telescopic cascode amplifier. The amplifier is appropriate for various brain signal frequencies as the achieved gain across the complete 50 kHz bandwidth is 39.78 dB. In comparison to current solutions, the design exhibits notable increases in power efficiency, with an ultra-low power consumption of 0.18 μW and a Noise Efficiency Factor (NEF) of 2. These characteristics ensure dependable performance for brain signal processing in BCI systems, making the proposed neural amplifier the ideal choice for energy-constrained implantable devices.