Impulse relay...

[Sender]

Hey guys, I was looking for a relay that, via a momentary switch, would toggle states. After some googling, I found the Impulse relays do this. The only problem is that Mouser and DigiKey sell 'Impulse Relays' but they're big, and expensive (ie. 50+ bucks).

Is there any other name that 'impulse relays' might go by? Or a way to retrofit a more standard relay to do so? I'm new to relays and wanted to mess around, so any help would be great.

 

[Kit]

Impulse relays share the same function as a "flip-flop" circuit.

Google "discrete flip flop".

what are you switching? Power or audio?

Hook the collector up to a coil or fet and youre set to go. :sam: :sam:

 

[Sender]

[quote author="Kit"]Impulse relays share the same function as a "flip-flop" circuit.

Google "discrete flip flop".

what are you switching? Power or audio?

Hook the collector up to a coil or fet and youre set to go. :sam: :sam:[/quote]

I'm switching power. I googled discrete flip flop and everything was overly complicate (I'm still bit of a noob).

Any one read you recommend?

 

[mcs]

[quote author="Sender"]I'm switching power[/quote]
Will the relay be switching off it's own power supply? If so, use separate momentary on/off buttons like in motor control circuits.

Best regards,

Mikkel C. Simonsen

 

[Sender]

[quote author="mcs"][quote author="Sender"]I'm switching power[/quote]
Will the relay be switching off it's own power supply? If so, use separate momentary on/off buttons like in motor control circuits.

Best regards,

Mikkel C. Simonsen[/quote]

No

 

[PRR]

Two buttons:

 

[JohnRoberts]

You may be talking about a latching relay. Typical relays have a pull in coil and a restoring spring, so when power is removed from the coil the relay returns to it's rest state. A latching relay has two coils and no spring, so when you apply power to one coil or the other they change state.

The latching relay is more complex and more expensive with the primary advantage of zero current draw when closed or open. Since the common non-latching types are much cheaper unless you have a battery application, it is popular to wrap some simple logic circuitry around a non-latching type.

A one momentary push-push switch circuit could be generated with a cmos flip-flop (4013), but that circuitry would need power even when switched off. A single switch closure to alternately turn on power then turn it off is more tricky.

JR

 

[bcarso]

I believe there are actual toggling latching relays as Sender describes initially that have a mechanical means of steering successive momentary impulses to the contacts. I haven't seen one for many years, and they are big and clunky. I'm too lazy to go and hunt down the Digi part to which he refers to see if it is the same baby.

 

[JohnRoberts]

I can imagine using one relay switch pole to steer power alternately between two latching coils. Perhaps cap coupled to prevent oscillating if button is held.

JR

 

[EZ81]

Are these step relays what you need?
http://www.findernet.com/comuni/pdf/S26EN.pdf
They are commonly used for light switches in .de and cost less than 10EUR, but are still bigger than you might like.

HTH
;Matthias