The SAMA5D2-ICP board embeds one PAC1934. The PAC1934 is a four-channel DC power/energy monitor with accumulator. A 16-bit ADC is used to measure voltages across a current sense resistor, connected by a differential multiplexer to (+) and (-) inputs for each channel.
Four current sense resistors (10 mΩ) are populated on-board for measuring voltage on power rails:
The PAC1934 communicates with the MPU via a TWI bus.
The figure below shows the current measurement.
PIO | Mnemonic | Shared PIO | Signal Description |
---|---|---|---|
PC28 | PC28_PAC1934 | POWER TWI | TWI data |
PC29 | PC29_PAC1934 | POWER TWI | TWI clock |
PB17 | INT_PAC1934 | – | Interrupt |