ON/OFF circuit when it receive 3v signal. transistor? relay?

[fersev]

Hello,

I have not a lot idea about electronic, but I think I can do it...I need turn on a circuit when it receive a 3v signal. Can I do it whit a transistor? or I need a relay? If you know name of some component please tell me. I trying seaching on google but I do not put correct words smiley-sad

The circuit I need going to active consume 2 Amperes.

Thanks.

 

[Kuldeepluvani]

Yes you can use transistor. But you have not defined your turn off criteria. What if 5V comes it should remain ON or it should turn OFF. What if 2V comes? Please can you specify please?

 

[udhay_cit]

Fersev, please provide more information. Is it a digital signal or analog signal?

If it is a digital signal (0v or 3V) simple "transistor switch" in enough.
If it is analog signal (0V to 3V), better you go with an "OPAMP Comparator" circuit.

Give me the detail about the signal behavior...

The circuit which you are going to turn ON/OFF is consuming 2A current, you are recommended to use a relay circuit. Search for relay driver circuit.

Regards
Udhay

 

[smijesh]

Use Opamp voltage compactor circuit. Use LM471 or equivalent. Set 2.9v on the positive terminal of Opamp and apply sensing voltage (3v signal-Hope the signal is DC,If not put a diode) to negative terminal with respect to ground. The relay if on if the sensing voltage reaches above the 2.9V.

 

[fersev]

thanks all for your responses I think I will be in this forum for a long time

Is it a 3v digital signal that I want switch on/off an 2A LED circuit.

I will use an scheme like this:



My doubt is, what is the name that transistor that I need?

thanks

 

[fersev]

anyone knows about transistor name?

 

[zywts]

you can use a power transistor with low on resistance to achieve it. Just make sure no abs/max get violated

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forget to add this. for example this product, sorry link is a bit long **broken link removed**