USB - The Easy Alternative to Batteries
Batteries have always been the obvious choice to power a school project, but with our USB lead this doesn’t need to be the case. To make the lead easy to use it is supplied with just the two power wires coloured in red and black for ease of identification. The USB port on a PC runs at 5V and allows a 100mA load to be connected. This is sufficient to power most school projects.
When you consider the cost of a 3x AA battery cage and the batteries to go in it, the USB lead works out as a cheaper alternative. Furthermore unlike the batteries the lead won’t need changing. The lead is perfect for powering colour changing LEDs as well as standard LEDs (with the appropriate current limit resistor). A USB powered lamp kit, either with a white LED or colour changing LED, is also available and makes a nice computer lamp or mood lamp ornament.
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