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Spare 5V current for accessories

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Pimousse
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Spare 5V current for accessories

Hi Benjamin,

Do you have any idea how much spare current the 5V converter allows to draw for powering Arduino + WS2812 LEDS ?

Power comsuption on bench is not so high but with nRF module and so on, maybe ther's not enough room for this.

benjamin
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I think you can draw around 1A from the 5V supply, enough for a few leds at least.

Roger Wolff
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Benjamin, the WS2812 leds are a BEAST. First they use up to 60mA a piece. Secondly it is very easy to connect say 20 on the left side of your skateboard, and 20 on the right side. 2.4A Bingo! Moreover they are not very efficient: they use 5V, and waste 40-60% in the series resistor. 

IIRC the powersupply in the VESC was calculated to do 1A, of that you need to reserve 100mA for the VESC itself. That would leave 900mA, allowing up to 15 WS2812 leds..... 

benjamin
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Yes, the WS2812 draw quite a lot, it is easy to overload the power supply when not measuring the current at full brightness. The power supply is designed for 1.5A though, so I think that drawing 1A is quite safe. I have used it to power a raspberry pi 3 and their official 7 inch touch screen at the same time, but I would not recommend that at full cpu load on the pi.