The integration of a novel generation of implantable multi-electrode array probes based on CMOS technology is an emerging approach for recording electrophysiological signals from thousands of single neurons in-vivo. However, low-area and low-power consumption are mandatory and challenging constraints in such implantable circuits, such as for integrating and reading out signals from large number of recording amplifiers, each of them integrated underneath of each electrode-pixel. Here we present a modular solution that exploits resource sharing and power scheduling techniques to meet low-area and low-power consumption constraints. Each module comprises 32 active recording sites and occupies an overall area of 340µm×100µm. The achieved overall power density is of about 90pW/µm3. To test this solution, a first prototype chip was fabricated in a 0.18µm CMOS technology.