The Vintage 555 button debouncer

Buttons and tactile switches are frequently used in many projects involving micro controllers; one of the most frequent issue we met is related to unwanted multiple transitions when the button is pressed once.

Tactile switches, as well as push buttons are mechanical components subject to the problem of bouncing. When a button is connected to a digital GPIO input pin (i.e. an Arduino pin configured as INPUT) we ideally expect that when the button is pressed we get only one high digital signal; unfortunately this rarely happens. During the mechanical movement the physical material vibrates affecting the voltage and the transitions between the On/Off status are not so clear as we usually need. Micro controllers and FPGA are fast enough reading the microseconds oscillations when the button is pressed, resulting multiple readings while apparently we are pressing the button only once.

Read more on Element14 full post: Vintage 555

Digital Potentiometer Arduino Shield Reviewed by Freetronics.com

Screen Shot 2015-03-24 at 07.50.40We wish to thank the friends of Freetronics (Australia) for the review of the Digital Potentiometer Arduino Shield on their great blog.

The shield PCB or full assembly version can be bought on Tindie. for 10$ (or less, follow the discounts and promotions). See the Freetronics full blog post here.

Digital Potentiometer Arduino Shield on Electro Schematics

Screen Shot 2015-03-16 at 17.54.02Full description of the Digital Potentiometer Arduino Shield on the new article on Electro Schematics electronic site. The article can be found in the Arduino section.

Includes downloadable sketches of the programs shown in the video below, a complete description of the project, schematics, PCB layout and the digital potentiometer device data-sheet.

The shield PCB or full assembly version can be bought on Tindie. Follow the full description on the product page.