A simply and easy-to-make circuit, useful when working with the computer at night.This is a simple LED circuit that takes power from the USB port.
The circuit schematic is so simple: Just one resistor and one White LED.Use a 10,000mcd white LED. It illuminates perfectly the keyboard of any computer. In fact; it is so bright that, one can use it to read.
The USB cable have five wires: Two are used for data and two for power. The additional one is the grounded shield. The black one is the NEGATIVE, the red one is the POSITIVE. The voltage from an USB port is 5 Volts. The maximun current for any device connected to the USB cannot be more than 500 mA. Do not build this projects if you don’t know what you are doing.
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