AC current to logic output

[wisely77]

I would like to design a circuit that can detect AC current and giving logic output. A logic high for AC current detected and logic low for no AC source is available.

thanks.

wisely

 

[flatulent]

safety first

Safety is the first rule in these things. You should use a Hall Effect Sensor type of noncontact sensing device. This will give you an AC output voltage. Transform this into DC with a full wave op amp rectifier circuit. Then follow this by a low pass filter which can be just an RC network. Then put this signal to the input of a comparator.

 

[papyaki]

Hi

You can also use a HCPL3700, a high isolated AC/DC optocoupler with trigger.

The data sheet is available at :

https://www.fairchildsemi.com/ds/HC/HCPL-3700.pdf