Introduction

Modern process computers, commonly based on high-end 32- or 64-bit microprocessors, provide developers with significant options in terms of operating system use. However, their high processing power is paid for with equally high-power demand, which can be a problem in battery-operated real-time applications. Using a simple low-power and cost-effective 8-bit PIC microcontroller as the secondary device provides a convenient and cost-effective means of controlling the system power state. This discussion will consider the use of PIC16F microcontrollers in that role.

This application note demonstrates the use of the PIC16F15244 microcontroller in such applications for system power supply control. As a case study, for the demonstration, a reference application based on a Raspberry Pi© Single Board Computer (SBC) is used as the process computer (host) and a PIC16F15244 Curiosity Nano Evaluation Kit as a power supply control module (client). Additionally, the SBC functionality is also emulated with another PIC16F15244 microcontroller, as one of the use cases discussed in the application note. Sections 3.6 Process Computer Firmware Overview and 3.7 Supply Control Module Firmware Overview describe the process computer and supply control module firmware developed using the PIC16F15244 microcontroller and PIC16F15244 Curiosity Nano Evaluation kit. The PIC16F15245 microcontroller-based supply control board hardware design files are provided in supplemental files; links to these files are provided on the device product page on the Microchip web site. The application firmware is available as GitHub projects; direct links to the GitHub repositories are provided in the document.