The constantly growing embedded systems market uses micro-controllers or digital control systems for a huge number of applications. The ideal embedded controller should be one that is small and easy to integrate, easy to design with, features low power consumption to enhance battery life, and yet still provides enough performance for tomorrow``s product. According to these criteria, we have designed micro-controller featuring low-power consumption, small area, high performance. Since the power consumption for memory access dominates the total power consumption, it is important to design a micro-controller that reduces memory accesses as well as the power dissipated by the micro-controller itself. In this thesis, we suggest a new RISC micro-controller core architecture which minimizing the memory access by adopting an efficient 16-bit fixed length instruction set, by supplying the powerful power down mode and by allowing memory data to be transfered in 8-, 16- and 32-bit size for all load/store instructions. The power and performance are evaluated by comparing the instruction count of Dhrystone 1.1 code with those of other micro-controllers.