Using a unidirectional ACS715 with AC current


I wander what would happen if flowing AC current in a uni-directional current sensors such as ACS715. Will the chip fry ? Will it block reverse current ? Or will it just give no output (ie 0V or alike) when current is flowing in the reverse direction ?

My intent is to use such a chip to build an electrical appliance usage sensor. This boils down to detect the presence of a current above a given threshold, without trying to measure it. The reason I want to use a DC current sensor in place of a AC one is to double the sensitivity (thanks to the fact that the output signal is originated at 0V and not at Vcc/2), and thus to allow a reliable detection of low currents.

I have carefully read the datasheets of both kinds of chips, but could not find any information about this question. So I would be grateful if somebody could provide my some clue.

Thanks in advance

Best regards.


I don’t know anything beyond what is in the datasheet, but I don’t expect them to break or block reverse current since the sensed current just goes through a wire. I don’t know what the output will do (my expectation is that it will just work), so you would have to contact Allegro or try it out if you want more information. Please let us know what you find out.

- Jan

Thanks Jan for replying me quickly.

My guess is also that it will happen nothing harmful, and that the output will just be capped to 0 when current is flowing back. I’ll give it a chance to see, and post the results here in case it could be useful for somebody else.

Best regards