Electronic – How to debounce a low pulse switch for automotive lighting

automotivedebouncerelayswitches

Hoping you guys can give me a hand with some wiring that I can't quite figure out!

Background: I'm trying to rewire a set of automotive lights – these are normally controlled by a computer but I'm trying to bypass that. I'm using the original light switch which is low pulse, and all the original stuff past the fuse panel, including the relay to drive the lights themselves, so I'm just handling sending a control signal out to that.

Current Setup: Right now I've set up a latching relay that is triggered on the low pulse of the oem switch, and sends 12V to the lights to turn them on. It's working in general, pressing the button turns the lights on, pressing it again turns them off. It looks something like this:
Current Circuit

The issue: The switch bounces, resulting in inconsistent behavior. Lights flipping on and off rapidly when you press the button once, etc.

I'm pretty sure what I need is some kind of RC debounce circuit, but I can't wrap my brain around how to do it without short circuiting something. I only have access to the one wire coming from the switch, which is grounded when pressed.

I feel like there's something I'm missing here to make it work, any help would be greatly appreciated. I'm hoping that this can be solved without adding too many more components (a capacitor and resistor or two?) but I keep thinking my way in circles.

EDIT: Realized my diagram may be confusing. The 'Latching Relay' is not just a basic relay, it's a small circuit that's functioning as a latching relay. It's a black box to me though, I just supply +12V, Ground, and the low pulse input, and it toggles my 12V output. The issue is it's bouncing when I pulse the switch

Best Answer

With no information on what is in the box we can only guess. The first thing I would try would be to put a capacitor across the switch; .1 uF would be a good choice, maybe more?

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