This paper presents the integration of a 32-channel neuromodulation system on chip (SoC) which is developed for chronic implantation in humans. The ASIC offers low noise recording, a state-of-the-art (SotA) neurostimulator capable of both current and voltage controlled stimulation with highvoltage compliance, on-chip 16-bit data digitization as well as safety features like electrode impedance estimation and charge balancing. The chip communicates through two distinct SPI interfaces for independent command and data transfer. Thus, the developed system constitutes a fully digital, bidirectional 32channel interface to the brain.