Raspberry Pi power consumption

There is a difference between a "Charger" and a "Power supply" and the recommendation is to use Power Supplies. One of the reasons is that a power supply is design for constant usage a Charger is not. Be aware that some USB cables uses less copper (less area) and can cause problems as the voltage drop can exceed the one that is allowed. ## Recommended power supply

Model                      Recommended PSU current capacity
-----                      --------------------------------
Raspberry Pi 1 Model A     700mA
Raspberry Pi 1 Model B     1.2A
Raspberry Pi 1 Model A+    700mA
Raspberry Pi 1 Model B+    1.8A (Pi 1.3A ,USB 0.5A)
Raspberry Pi 2 Model B     1.8A (Pi 1.6A ,USB 1.2A)
Raspberry Pi 3 Model B     2.5A (Pi 1.3A ,USB 1.2A)
Raspberry Pi 3 Model A+    2.5A (Pi 1.3A ,USB 1.2A)
Raspberry Pi 3 Model B+    2.5A (Pi 1.3A ,USB 1.2A)
Raspberry Pi 4 Model B     3.0A (Pi 1.8A ,USB 1.2A)
Raspberry Pi 400           3.0A (Pi 1.8A ,USB 1.2A)
Raspberry Pi 5             5.0A (Pi 3.4A ,USB 1.6A) with PD (Power Delivery) 3.1 support
Raspberry Pi Zero          1.2A (Pi 0.7A ,USB 0.5A)
Raspberry Pi Zero W        1.2A (Pi 0.7A ,USB 0.5A)
Raspberry Pi Zero 2 W      2A

Ref.: https://github.com/raspberrypi/documentation/blob/develop/documentation/asciidoc/computers/raspberry-pi/power-supplies.adoc ## USB power And this is approximate numbers.

Model                  Max power output of USB ports
-----                  -----------------------------
Raspberry Pi Zero, 1   500mA per port
Raspberry Pi 2, 3, 4   1200mA total across all ports
Raspberry Pi 5         500mA if using a ~3A supply, 1600mA if using a 5A supply with PD 3.1 support

Ref.: https://github.com/raspberrypi/documentation/blob/develop/documentation/asciidoc/computers/raspberry-pi/usb-bus-on-raspberry-pi.adoc

A common misconception is that a power supply must be example 3.0 Amp for a Raspberry Pi 4 and that is NOT true. A Raspberry Pi needs a power supply that can deliver the Raspberry Pi 4s max power consumption. And as seen in the table above the max consumption for the Raspberry Pi 4 is 3.0A and that is 1.8A for the Pi and 1.2A for USB devices. And as can be seen here (https://www.pidramble.com/wiki/benchmarks/power-consumption) is the idle consumption for a Raspberry Pi 4 approx. 0.54 Amp. If the Pi is just idling a 0.54 Amp power supply is enough to power the Pi, but if the Pi is doing something and the power consumption goes up that power supply will not be able to supply that power. This will result in a low voltage from the power supply and lead to a reboot in best case. Note: This will also cause the power supply to age faster and probably fail in a near future.

## Power Consumption Benchmarks https://www.pidramble.com/wiki/benchmarks/power-consumption ## Reducing Raspberry Pi 5's power consumption by 140x https://www.jeffgeerling.com/blog/2023/reducing-raspberry-pi-5s-power-consumption-140x