Introduction

Embedded applications often rely on analog inputs. Most Microchip MCUs are equipped with an integrated Analog-to-Digital Converter that can be used to gather data from the physical world. A baseline ADC will be sufficient to gather data under ideal conditions, but end-user operating environments are often far from ideal. Noisy on-board circuitry, noisy environments, and noisy power supplies are common examples of complicating factors. Conventional ADCs will often require hardware circuitry and firmware routines dedicated to signal conditioning, but Microchip’s latest ADCs remove some of this overhead through advanced Core Independent functionality.

The new 12-bit ADC offers true differential measuring capabilities with optional hardware accumulation of up to 1024 samples, which effectively gives up to 17 bits resolution. With sampling rates up to 375 ksps, the analog data is rapidly available. The Programmable Gain Amplifier (PGA) for the ADC can amplify single-ended and differential analog inputs to make it possible to measure even small amplitude signals efficiently.

This training manual goes through assignments that give a general introduction to the ADC module. Some of the assignments are more specific to the 12-bit ADC and demonstrates the added features such as the PGA. Basic theory related to each assignment is introduced at the beginning of each assignment, then the functionality is verified through the MPLAB Data Visualizer. Every assignment is provided with a preconfigured code, where most code is already in place, and only essential modules for the specific assignment need to be configured.