Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

555 timer help

Status
Not open for further replies.

bubsta82

New Member
I have found a simple 555 timer circuit; however, I need to change the button mechanism to something more suitable. It operates with an on-off push button switch but I am just wondering how pin 3 output could be turned on and off with a momentary switch instead of an on-off. only because i can only find a momentary switch small enough (tactile) to suit my needs. If there is a simple way or another switch that would help? All i need to do is turn off and on pin 3 output with the smallest switch possible.
https://i39.photobucket.com/albums/e151/bubsta82/555timercircuit.jpg
 
Last edited:
555 momentary switching circuit

Bubsta,

Here's a 555 timer circuit that operates from a momentary switch.

The transistor in your schematic is replaced by a logic FET, which acts as a relay for whatever you want to switch on/off

In this one it is operating an LED Torch, however you can replace the LED by whatever you want to switch on and off
 

Attachments

  • new toggle circuit.jpg
    new toggle circuit.jpg
    22.4 KB · Views: 1,306
I m just looking to see if there is a simple way to basically let a momentary be used to push once to shut the oscillation off and once pressed again start the oscillation again... and so on. and the higher the frequency the better this would work for me. Which i assume is by adjusting the values of the external Cap and resistors.
 
Use a JK-Flip-Flop to be connected to the pushbutton. Connect Q of the Flip-Flop to the reset pin of the timer via an NPN-transistor. When Q is high the timer stops oscillating keeping the output (pin3) low. When Q goes low the timer will run.

Boncuk
 

Attachments

  • TOGGLE-3.gif
    TOGGLE-3.gif
    17 KB · Views: 465
hey just curious if this would help? After a lot of research i might have found a couple ways to achieve what I am looking for.

Circuits Page 9

What I am looking at is a little ways down titled
"Relay Toggle Circuit Using a 555 Timer"
 
hey just curious if this would help? After a lot of research i might have found a couple ways to achieve what I am looking for.

Circuits Page 9

What I am looking at is a little ways down titled
"Relay Toggle Circuit Using a 555 Timer"
 
hey just curious if this would help? After a lot of research i might have found a couple ways to achieve what I am looking for.

Circuits Page 9

What I am looking at is a little ways down titled
"Relay Toggle Circuit Using a 555 Timer"
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top