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Raspberry Pi Power

In the referenced entry, OP (me) makes a curious statement about the Raspberry Pi power usage: "Uses too much power"...

gemini://gemini.ctrl-c.club/~stack/gemlog/2022-05-27.pi.gmi

makes the opposite claim (4W at 5V?)

So, to clarify, the pies need a really solid 2A 5V power supply, which looks like 10W to me. Does it ever use less, like 4W? Not in my experience. 10W is still pretty good.

The (old?) Pi uses an old micro-USB (I think that's what it's called) connector, which is really, really flimsy. But for a while all phones in the US used that form factor, so chargers were abundant. Aliexpress sold them for like a $1.00, free shipping. Those were the days.

Like many things from China, most cheap power supplies (and some more expensive ones) were complete junk. I have a large box of them. Some of them provided so little power (< 0.5A) that the Pi would not even boot, even those advertising 3A. Others would boot it, but run it in a throttled state; or blink the 'underpower' light (yes, there was and maybe still is a light for that).

It took me too long to figure it out - I had a USB power supply that worked just well enough most of the time that it was always a mystery.

Actually, the micro-USB connector and the USB standard call for power supplies that do not provide adequate power. The cable is rated for 500mA, not 2A, so even if you have an overpowered supply, a cheap cable can cause a voltage drop rendering the Pi useless.

So to power a Pi you need a non-standard, out of spec, USB power supply. These days you can pick one up on Amazon for $10-$20.

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