The rules have changed for system designers. Forget the comfortable notion that designing for low-power and low-cost eliminates the need to consider 32-bit microcontrollers. As if system designers didn’t already have a tough enough task, they now must carefully consider a wider assortment of CPU architectures before identifying the best solution that meets cost, power and performance constraints. Now that ARM-based microcontrollers sell for as little as a dollar, an economic barrier has shattered, and RISC microprocessors now have to be seriously considered for almost any microcontroller application.

The primary goal of this article is to analyze some of the technical trade-offs facing system designers as they work to identify the pros and cons of using a 32-bit microcontroller in applications where an 8-bit device offers sufficient performance.

Reprinted in its entirety from ARM IQ Vol. 5, No. 3, 2006