5.4.4 Voltage Reference (VREF)
AVR and PIC32CM MCUs provide programmable Voltage References (VREFs) that supply stable reference voltages to analog peripherals such as ADCs, DACs and ACs. Both AVR and PIC32CM VREFs are designed to enhance measurement precision, support low-power operation, and allow easy configuration of the reference source for different application needs. Table 5-17 shows a comparison of features between the two.
| Feature | AVR® VREF | PIC32CM VREF |
|---|---|---|
| Integration | Stand-alone VREF peripheral | Integrated into the Supply Controller (SUPC) peripheral |
| Reference Voltage Options |
Multiple internal voltage External VREF pin |
Multiple internal voltages External VREF pin |
| Target Peripherals | ADC, DAC, Analog Comparator | ADC, DAC, Analog Comparator |
| Programmable Levels |
Varies per device family: 0.55–4.096V |
Varies per device family: 1–4.096V |
| Low-Power Support | Yes | Yes |
| Configuration | Software registers | Software registers |
| Additional Features | Simple routing to analog blocks | May include advanced supply management features |