IC relays

Discussion in 'General Electronics Chat' started by merwyn, Jun 14, 2010.

  1. merwyn

    Thread Starter New Member

    May 30, 2010
    guys do we have any ICs that work like relays, coz i don't want the clicking sound of relays in my ckts....

    pls help me
  2. Ghar

    Active Member

    Mar 8, 2010
    Yes, that's one of the purposes of a transistor... or an analog switch.
    It entirely depends on the current and voltage characteristics of what you're doing and how you want to drive it.
    Relays provide physical isolation when switched off which a semiconductor doesn't do.
  3. beenthere

    Retired Moderator

    Apr 20, 2004
    Being able to switch using analog switches or transistors will have to do with the signal switched and/or the power.
  4. Potato Pudding

    Well-Known Member

    Jun 11, 2010
    Solid State Relays seem worth suggesting.

    You have to plan for them to short out so fuse them well, then use them well.

    Look at a few datasheets anyways.
  5. merwyn

    Thread Starter New Member

    May 30, 2010
    transistors just switch on and off a circuit. I need something that works exactly like a mechanical relay ' when there's a signal it must switch on a circuit and when the signal is gone it must switch on some other circuit'
    can u name any solid state relays mr pudding
    and ur quote is well mr. beenthere
  6. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    You still use transistors... or optocouplers. you might just need 2 to perform the functions you need.
  7. BillB3857

    AAC Fanatic!

    Feb 28, 2009
    Exactly what kind of signals are you switching? AC, DC, current levels, voltage levels? Makes a difference in the type of device to be used.
  8. gerty

    AAC Fanatic!

    Aug 30, 2007
    A schematic would help also, so we can see what is compatable for coil current/voltage.
  9. Potato Pudding

    Well-Known Member

    Jun 11, 2010
    Look up Solid State Relays or Omron (a leading manufacturer) in a catalog like Mouser

    Info that I am guessing at -
    You need the relays to switch AC power with a DC control circuit.
    You don't need more than standard 120VAC for the output.

    The datasheet here includes models that will do that and some variants.


    Optocoupling for input output isolation is used in every Solid State Relay I can think of and I may just have a mental habit of thinking of DC output control for Optos and AC outputs controlled with an SSR, when I know that some devices of both names can be set up for either type of output.

    I am not sure if you would be making any mistake by calling an OPTO an SSR and an SSR an OPTO.
  10. Potato Pudding

    Well-Known Member

    Jun 11, 2010
    Sorry I didn't notice earlier that you wanted a Double Throw relay.

    I see what you mean about transistors just switching circuits on and off.

    But with transistors they made logic chips, computers, and all sorts of other fun stuff.

    The SSR or Opto will mostly just take care of switching stuff on and off. It is not that they can't build the logic in and make a DPDT or 18P3T SSR, but it just is not worth it. put your logic or programming together, put an SSR on every output circuit then with the logic and computer to execute have everything plan out all the timing and turn everything on and off as needed.

    Almost every SSR will be normally open SPST.