IC 74HC595 8 Bit Shift register

IC 74HC595 8 Bit Shift register

Product information:

The 74HC595 IC is an 8-output shift register.
In other words, you can use this to drive 8 outputs while only using a few pins on your Arduino or Raspberry Pi.
You can even link multiple registers to get even more output pins.
Look at the pinout of the 74HC595 in the second image.

See how it works on this page: http://arduino.cc/en/Tutorial/ShiftOut

You can find more information about how it works in the datasheet.

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