Breadboard Button

Breadboard Button

Breadboard Button
a breadboard friendly debounced button with toggle and pulse functions. Use it for glitch-free input to your project. The board outputs positive and negative logic button state (active while the button is pressed). An additional FCN output toggles on each press or generates a 10 millisecond pulse on each press with 50 pulses/second automatic repeat.

Design Documents

Schematic Diagramschematic_J129_breadboard_button.pdf
Bill of MaterialsBreadboard Button BOM.pdf


Power Requirement3.3V to 5.0V
OutputLogic level, 25mA maximum

The Breadboard Button PCB is designed to plug into two rows of a standard breadboard and remain stable, like this:
Breadboard Button

There are 2 power pins

VCCLogic supply voltage, 3.3V to 5.0V
GNDLogic ground

There are 3 output pins

BTNDebounced button, positive logic (HIGH when the button is pressed)
/BTNDebounced button, negative logic (LOW when the button is pressed)
FCNToggle or Pulse output

The BTN and /BTN outputs are real simple; as long as the button is pressed the output is active.

The two pin jumper selects the FCN pin operation:

No JumperFCN pin toggles on each press
Jumper InstalledFCN pin pulses for 10 msec, then repeats at 50/sec after 1 second (press button to generate 1 pulse, hold to generate continuous pulses at 50Hz)
The onboard LED indicates the FCN pin output state

Breadboard Button
Adding a jumper across the two bottom feet pins changes the button FCN output from toggle to pulse.