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Light up keyboards


I wanna buy a light up keyboard but the problem is I have found that light up keyboards cause energy-wasting (I read in this article Is it true??

Well, of course extra RGB would cause higher usage of energy, but in any case you can just turn them off

Is keyboard power consumption a concern? Are you looking for a bluetooth board too?

If you read the article you would have seen that they ask "Is it true that light-up keyboards consume more energy?" and then answer it with "The answer is yes, although in insignificant proportions.".

However in their conclusion they state "Contrary to common perception, light-up keyboards do not consume more power than conventional keyboards do.", which directly contradicts most of what tis stated earlier in the article.

Not a very consistent article.

However, backlit keyboards do consume more power - something had to make the LEDs glow.  But the amount of power is not significant, except in the case of a bluetooth keyboard.

If it really bothers you, using a more power-friendly computer, like a Raspberry Pi or similar, would save considerably more energy than using a non-backlit keyboard.

The max power draw of a USB 2.0 device is 500 mA. 500 mA 5 V = 2.5W.
RGB backlit keyboards often draw just under that at maximum brightness.
A modern office keyboard without backlighting, or with backlighting off can draw as little as 3 mA.
But a USB keyboard with a less modern microcontroller (such as the ATmega32u4 that is common in custom keyboards) could easily draw 50 mA.

However, if you're using a USB hub or a power-limited computer (such as a cell phone) the keyboard's actual power draw is not the only issue.
When a USB device is connected it has to declare its maximum theoretical power draw to the host computer, and the host will decide if that is too much within the port's power budget.
This means that you might not be able to use a backlit keyboard on a USB hub or a cell phone even if the backlighting is switched off.


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