Signal detect and switch

[jasko_jacker]

As a part of an electronic circuit, I have three signal on 3 wires, x) 5V y)GND z)2V AC
but I don't know what wire has the 5v signal, GND, and AC . I'm searching a method or an IC that detect
the signal type , I think it's easy with a micro compare the signal but after comparing ,
I'd want to use the 5V 2A to power for example a led....
any idea
thanks

[stj]

Re: Signal detect and switch

use a multimeter.

[budm]

Re: Signal detect and switch

use a multimeter.

+1, and also upload the pictures so we can see what we are dealing with.

[Curious.George]

Re: Signal detect and switch

As a part of an electronic circuit, I have three signal on 3 wires, x) 5V y)GND z)2V AC
but I don't know what wire has the 5v signal, GND, and AC .

Is the "AC" signal sinusoidal (or, of some waveform known a priori)?

What's the driving impedance of each?

If all you're looking to do is drive an LED, then use a bunch of diodes as switches; to detect polarity as well as "largest potential"

[exercise left for the reader]

[stj]

Re: Signal detect and switch

no, use a multimeter - because your post implys that you dont have one - at it's an essential item.

[Curious.George]

Re: Signal detect and switch

no, use a multimeter - because your post implys that you dont have one - at it's an essential item.

The OP's post suggests that he wants to do this repeatedly -- "as part of an electronic circuit". I.e., as if he (or, some unskilled consumer) will be connecting groups of three conductors to his circuit and expecting the circuit to automatically sort out how to find the power&gnd from which to drive his indicator.

If it was a one-off event, there's hardly any challenge...

Sort of the same idea as making a "plug" that can mate to an AC mains receptacle and tell you if the receptacle is wired correctly. A multimeter (and a printed chart explaining how to interpret the results) would be a poor solution if the average homeowner was the intended customer!

[stj]

Re: Signal detect and switch

it sounds to me like he has 3 wires - i assume there is some colour-coding on them.

[Curious.George]

Re: Signal detect and switch

it sounds to me like he has 3 wires - i assume there is some colour-coding on them.

It sounds to me that he will be encountering this group of three wires repeatedly and wants to ensure that the circuit he's designing (to connect to them) will be able to sort out which is which -- without having to ship a multimeter with each circuit and detailed instructions on its use.

I did something similar with my thermostat's electrical interface to ensure customers don't have to study a manual telling them how to connect it to their wiring (and, hoping the original installer adhered to the right color code when he ran the wires through the house).

[As well as hoping the homeowner installing the thermostat isn't colorblind -- 15% of men, are]

[eccerr0r]

Re: Signal detect and switch

Time to ignore the thread until some clarification on what the intended use of the circuit is.

[budm]

Re: Signal detect and switch

time to ignore the thread until some clarification on what the intended use of the circuit is.

+1

[jasko_jacker]

Re: Signal detect and switch

Hi,
The goal is to make a Circuit (very small 2 cm x 2 cm) to detect some signal coming from consumer electronics unit (as soon as possibile I'll post a part of the circuit) and after use those signal ......
For example a similar thing as mega 328 all in one component tester .
all this to prevent the person using this circuit from manually setting the position of the cables.

[stj]

Re: Signal detect and switch

3phase bridge rectifier with 6 diodes and a small cap will do it.

[eccerr0r]

Re: Signal detect and switch

I still don't get it. So you have three identically labeled output connectors and you have an LED that you want to light no matter how you connect three wires to those connectors? Seems very odd.

The 3 phase bridge rectifier should work, yes, minus the drop; but you need this rectifier in any solution.

Else I don't see why not just hard wire a special connector that only fits one way. Still don't see the point of this.

[Curious.George]

Re: Signal detect and switch

I still don't get it. So you have three identically labeled output connectors and you have an LED that you want to light no matter how you connect three wires to those connectors? Seems very odd.

The 3 phase bridge rectifier should work, yes, minus the drop; but you need this rectifier in any solution.

Else I don't see why not just hard wire a special connector that only fits one way. Still don't see the point of this.

Consider that connector as not yet having been fitted to the wires (e.g., like the wires to a household thermostat). Then, reimagine the problem as:

"I have three wires that need to be fitted to this polarized connector such that when the connector is mated to this little PCB, the indicator will light in the presence of a particular signal"