74595 IC 8-Bit Serial to Serial/Parallel

• Revised 74HC595 Description (Active Voice Focus)

   

  The 74HC595 is a very handy IC. Users utilize it in many microcontroller projects. You clock in 8 bits of data (like on/off settings for 8 LEDs) using two lines. Then, when you toggle a third line, the IC pops these settings out on 8 dedicated outputs. Consequently, you trade 3 valuable lines on your microcontroller for 8 outputs—a pretty good deal, eh?

  We call this process “Shifting data out” of the microcontroller by “synchronous serial communication.” This handles the serial part of the deal, where the system “shifts in” each bit one at a time. Then, BOOM, they all appear at once (in parallel) on the chip’s output.

  Great tutorials show you how to use a shift register. Here’s one for the Arduino microcontroller, but the technique holds true for pretty much all microcontrollers!

   Here’s one

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  74HC595 Features

   

  • It is a shift register with 8-bit serial input and 8-bit serial or 3-state parallel outputs.
  • The IC operates from 2V to 6V.
  • The output voltage equals the operating voltage of this IC.
  • It is based on CMOS logic and consumes a very low power of $80\mu \text{A}$.
  • The output source/sink current is $35\text{mA}$.
  • It features high noise immunity.
  • Users can easily cascade it through pin 9 with more ICs to get more outputs.
  • The maximum clock frequency reaches 25 MHz at $4.5\text{V}$.
  • Schmitt trigger action is provided on all inputs.

   

  SN74HC595 Applications

   

  This IC has a multitude of applications. Developers use it in wide arrays of products such as computer peripherals, appliances, etc. A few applications include:

  • Holding Data for a long time period
  • Serial to Parallel Data Conversion
  • General Purpose Logic
  • Controlling LEDs