2.4.3 Analog and I/O Power
Contrary to the core logic power described in the previous sections, the power consumed in the analog and I/O cells has a low temperature dependence. Typically, it drifts by about 10 to 20% over the whole temperature range of the device. This power depends on the application use case (number of PLLs used, number of USB ports used, ADC enabled or disabled, MIPI D-PHY enabled or disabled, number of serial ports in use and their speed, GMAC interface use and its mode, etc.).
Tip: This power can generally be reduced by operating the
device power rails at lower and optimum operating voltages. For instance, interfacing a
Gigabit Ethernet transceiver(1) at 1.8V consumes less power than at 3.3V. Similarly, avoiding high
voltage conditions on 3.3V inputs, i.e., avoiding 3.6V, by choosing accurate voltage
regulators(2) is a good practice to keep the rail away from
unnecessary power dissipation.
Note:
- Microchip Gigabit Ethernet transceiver KSZ9131 or LAN8840 can be interfaced at 1.8V.
- Microchip MCP16501/502 Power Management Integrated Circuits (PMIC), with better than ±3% accurate voltage regulators, are recommended power supply solutions.