2 Usage of PIC16F15244 Family of Microcontrollers for System Power Supply Control

Consider a high-end application developed on the Raspberry Pi Single-Board Computer (SBC). The SBC consumes plenty of power when active, and may not be needed at all times. In order to save maximum power, the power supply to the entire SBC should be cut OFF, instead of just shutting down the CPU. To perform this action, a PIC16F15244 family microcontroller is used as a secondary microcontroller in the system to turn OFF and ON the SBC power using the voltage regulator. After turning OFF the voltage regulator, the microcontroller can enter Sleep mode to further reduce the system power consumption.

Figure 2-1. System Power Supply Control Using the PIC16F15244 Family of Microcontrollers

(As previously discussed, the power control system may be realized with any 8-bit PIC microcontroller.)

There are numerous possibilities when to turn the regulator ON or OFF. For example, an intelligent host can give a command to the client to switch the power OFF and for how long it should stay OFF. User interface-based turn ON and OFF are also possible. An example of this is wake-up on touch. The application can thus be extended in multiple possible ways. One such use case is discussed in this application note.