555 Timer IC Resistor and Capacitor Tables

I made this spreadsheet for my own use with respect to calculating resistor and capacitor values for the 555 timer IC. Some others may find this useful.

The zip file contains an image, an Excel spreadsheet, and a PDF.

The image contains schematics of both astable and monostable oscillators using the 555.

The spreadsheet's first worksheet is a calculator where you can plug in values and get results. The other worksheets are pre-calculated tables for ready reference.

The PDF shows only the tables and is handy for print-out.

On the calculator worksheet, I've provided a pop-up of some standard resistor values and capacitor values but you can key-in your own values if you like other standard values or are combining components to get specific values. If you know how to set cell validation in Excel, the standard values are off to the right in columns W and X. You can add your own values and then redefine the cell validation range.

On the worksheets with the tables of values, you can edit the B4 cell to change the R1 values to make your own table of values. The rest of the cells are protected but there is no password so you can un-protect the sheets and edit everything if you want to. You might want to do this if you want tables of higher frequencies. For example, if you change R1 to 1K, un-protect the worksheet and change R2 to 1K, then at C=0.01uF you get F=48KHz.

Have fun with it.

I wouldn't connect that if I were you...

Vive Le Tour!
Le Grand Depart July 6-8, 2007

Post Edited (aalegado) : 1/4/2007 4:17:21 AM GMT


  • 2 Comments sorted by Votes Date Added
  • edited January 2007 Posts: 0Vote Up0Vote Down
    Very cool and very useful! I wanted to add a simple sound generator to my new robot, but don't want to tie up the Stamp with "freqout" commands... your worksheet will enable me to play with R and C values much easier than lots of soldering and unsoldering!

    Thanks again!
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