Abstract
This paper reports on the design of a low-power biostimulator, capable of generating stimulus pulses with arbitrary wave shapes and programmable amplitude and timing. Designed based on a modular architecture with programmable stimulation details, this system can be used in a wide variety of applications. The system complies with basic requirements for biomedical stimulation systems such as small physical size, serial data communication with external setup, and low-power consumption. It also performs basic functions such as generating bi-phasic pulses, single/train pulses, and residual charge cancellation. Clock gating, operation with external timing, and shared resources are used among the main techniques to significantly reduce the power consumption of the system. To wirelessly interface with the external setup, a BPSK demodulator and clock recovery circuit is used which exhibit 100% data-rate-to-carrier-frequency ratio and consumes as low as 120µW at 2.5Mbps. The system was designed and simulated in a 0.18-µm standard CMOS technology, prototyped for functional verifications, and successfully tested.
