Microcontrollers have a relatively wide range of operating voltages. Supplying lower voltages, however, makes it impossible to run the CPU at full speed, and flash memory may require additional wait states due to the physical characteristics of the hardware. Nevertheless, lower-voltage-tolerant logic may improve the overall economy of the system in some cases.
Internal regulators are often configurable to produce a lower voltage for the core signals, to reach a compromise between power consumption and performance, when the CPU is not running at its maximum frequency.
An important aspect that is often neglected is the power consumed by the Schmitt triggers in the digital input logic. When GPIOs are configured as digital input, ...
