How to interface with doorbell?

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jjinno
 
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How to interface with doorbell?

Post by jjinno »

I'm generally aware that doorbells run on AC that has been transformed down to a meager 16-20VAC... However, that doesn't allow integration yet with any microcontrollers.

I would imagine that an AC-to-DC power supply would essentially fit the bill (schematic wise) but for the life of me cannot find any that will accept the 16-20VAC input coming from the doorbell.

Another problem with AC-to-DC is the caps they typically use to smooth out the voltage. They are so large that the DC voltage sticks around for significant amounts of time after AC had departed.

Once DC, even 16-20VDC is relatively easy to take care of turning into logic-level voltage. Of course, if somebody has a link to a 20VAC-to-5VDC relatively-lag-less converter

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zener
 
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Re: How to interface with doorbell?

Post by zener »

You could use an AC coil relay or a DC coil relay with a rectifier or an AC input optocoupler.

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jjinno
 
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Re: How to interface with doorbell?

Post by jjinno »

Shoot... Maybe I was overthinking things here.

I think I am going to start by buying myself another solenoid like this one but AC (for a doorbell) and just have it press a digital button for me...

After all, my OP does just say "interface with"... And I just steered into the weeds maybe...

Of course, as I also stated, if anybody knows where I can just buy the thing I need, no assembly required, then please do let me know.

;-)

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zener
 
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Re: How to interface with doorbell?

Post by zener »

AC input opto coupler such as LTV824. You would need a couple resistors also. Maybe a capacitor also.

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