How to make toggle latch?

Discussion in 'General Electronics Chat' started by secrect, Feb 12, 2009.

  1. secrect

    Thread Starter Member

    Feb 1, 2009
    16
    0
    Actually I want to make a toggling switch with latch which drives the relay without using any ICs... How can I do this ?
     
  2. thingmaker3

    Retired Moderator

    May 16, 2005
    5,072
    6
    You can make the latch with relays or other discreet components, as was done before ICs were developed.
     
  3. john-campbell

    Member

    Feb 10, 2009
    15
    0
    Do a search on the web for "latching relays". There are lots of them. Use a pushbutton switch or similar to provide an appropriate pulse to the relay. Each time the pulse is applied to the relay it will switch to one of its two stable states.
     
  4. secrect

    Thread Starter Member

    Feb 1, 2009
    16
    0
    Thanks for quick reply, but what I want to kindly ask is, Let's not include that relay... I just want to on and off a LED using single push switch. At the very first the LED is OFF. When I press the switch the LED should ON and on next push It should OFF. and circuit should not use any ICs and simple too.
     
  5. john-campbell

    Member

    Feb 10, 2009
    15
    0
    Sounds like what you want is an "alternate action" pushbutton. The first push sets it to one state and the next push sets it back to the other state. Same thing. Just do a search for "alternate action bushbutton"
     
  6. secrect

    Thread Starter Member

    Feb 1, 2009
    16
    0
    If I'm correct... It's electromechanical technique but I need to give it pulse for ON and OFF.
     
  7. john-campbell

    Member

    Feb 10, 2009
    15
    0
    I confess. I'm mystified. It's either a mechanical switch or an electronic latch. We're back to using an IC latch. Something has to store the ON-OFF state.
     
  8. secrect

    Thread Starter Member

    Feb 1, 2009
    16
    0
    Can't we do this without using ICs... help me...
     
  9. Ron H

    AAC Fanatic!

    Apr 14, 2005
    7,050
    656
    Why can't you use an alternate action pushbutton switch, as recommended by john-campbell?
    If you need it to be actuated by a pulse, and you don't want to use ICs, can you use transistors?
     
  10. KMoffett

    AAC Fanatic!

    Dec 19, 2007
    2,574
    230
  11. Ron H

    AAC Fanatic!

    Apr 14, 2005
    7,050
    656
    I wondered the same thing. A Google image search brings up some fairly nasty George Bush lapel buttons.
     
  12. john-campbell

    Member

    Feb 10, 2009
    15
    0
    You guys are a tough crowd. I'll be more careful in the future.
     
  13. eblc1388

    Senior Member

    Nov 28, 2008
    1,542
    102
    Many years ago I did a alternative push button ON/OFF relay circuit to replace one of those mechanical switches used on a table lamp.

    The only limitation is not to use any latching relay or capacitor or transistors and the circuit should be able to work with either AC or DC coil voltage.

    I can't remember the details now but I did remember I have to use more than three relays.
     
  14. secrect

    Thread Starter Member

    Feb 1, 2009
    16
    0
    Yes, We can use transistors...
     
  15. Ron H

    AAC Fanatic!

    Apr 14, 2005
    7,050
    656
    Is your input a switch, a pulse, or...:confused:
     
  16. secrect

    Thread Starter Member

    Feb 1, 2009
    16
    0
    It's a pulse.
     
  17. KMoffett

    AAC Fanatic!

    Dec 19, 2007
    2,574
    230
    What is the source of the pulse? Voltage? Polarity? Pulse width?

    Ken
     
  18. secrect

    Thread Starter Member

    Feb 1, 2009
    16
    0
    Whatever you want but it should be pulse.
     
  19. KMoffett

    AAC Fanatic!

    Dec 19, 2007
    2,574
    230
    Now that's license. :) Since the pulse can be anything...I choose "momentary, dry-contact switch closure"! ;)

    Not my circuit, but I always thought it was a novel idea. :)

    Ken
     
  20. secrect

    Thread Starter Member

    Feb 1, 2009
    16
    0
    You're with the license but It's prohibited to use such mechanical control... Let's say the pulse is of electrical type... and this circuit should behave as the JK Latch... but without using ICs... can be used transistors and passive frens....
     
Loading...