Design of Low Power, Low Noise with High Output Swing Preamplifier of Cochlear Implants

Cochlear implantation is a procedure that uses electrical stimulation in the auditory nerve system to restore partial hearing. In this work, a low-power, high-gain with high output swing preamplifier has been designed for a cochlear implant. Capacitive feedback topology is used along with the current scaling resistor to maintain the noise under the limit and to overcome the trade-off between noise and power. Simulations and post-layout analyses for the proposed preamplifier were done in Cadence Virtuoso using UMC 180 nm technology. In the proposed OTA, a maximum gain of 44.23 dB, total average power of l. 69$\mu$W, a phase margin of 45 degrees, and noise of 2.71 $\mu$V/sqrt(Hz) at 1 Hz are obtained. Also, we have analyzed the capacitive feedback closed loop OTA in which we have obtained a maximum mid-band gain of 43.75 dB, and bandwidth of22.55 Hz to 18.55 kHz.