4-Position Switch Using a Momentry Switch

I need to create a simple circuit that will mimic a 4-position switch, and cycles through these with each push on a momentary switch. The 4-way states would be like a SP4T with one common input switched to one or both of two outputs: A-On, B-On, A&B-On, All Off. It would be like a 3-level lamp switch, in fact it's for a lighting application using LED strips. It would be for controlling 24V and 5 amps or less. I've seen a basic 2-state, On/Off toggle like this using latching relays. But I can't think through how I would combine two or three to achieve what I'm after, and I haven't found it done by anyone else, yet. Something that uses latching relays would be fine, but switching transistors might be better. Any body seen one they can direct me to? Or got your own idea you can suggest? Much appreciated.

by BrightWood
March 03, 2013

You need to post more info.

What does you power supply source look like?

What does the load look like?

A design spec.

A block diagram.

BTW:

"A-On, B-On, A&B-On, All Off."

That's just two SPST switches with 4 possible states.

:)

by signality
March 04, 2013

I don't have much more detail than that. Which conversely means I'm open to specifications imposed by the solution.

Power supply is 24V DC from an electronic transformer.

Load is 2 to 4 amps to High Power LED Flexible Light Strips.

Hmm, a block diagram? Okay. Here is at least a conceptual diagram of what I mean. It's not a professional level schematic, but please note that I'm in the newbie section here. It shows one 24V in, two 24V out, S1 is a momentary N.O., it cycles through 4 states – all permutations of L1 and L2 On or Off. The black-box portion is the circuitry I'm needing help with.

Also, here is the only schematic I have found that is closely related to what I'm trying to accomplish. But it has only one out that is either On or Off. I'm including this to help explain what I mean.

Perhaps the A/B description I used was poor nomenclature that implied separate SPST switches. You do understand that I'm trying to control these states with one momentary switch, right?

by BrightWood
March 04, 2013

No short circuit protection.

No fuse.

Need to choose logic family and devices then logic supply to match.

Switch MOSFETs must be fully turned on by a gate voltage equal to the logic supply voltage, i.e. Vgs_th << Vlogicsupply_min.

Detail of logic supply not shown.

by signality
March 05, 2013

This is almost exactly wat i need to bypass my tcu in my aw4 auto transmission the only difference would be reverse order in positions 2 and 3 and i also need a way to shift back down thru the sequence. I know its possible seen it done before but this is my first adventure into the world of electronics and i saw this thread searching thru google if anyone could share some advice id appreciate it

by CALIjeeper
March 05, 2013

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