Use this forum to chat about hardware specific topics for the ESP8266 (peripherals, memory, clocks, JTAG, programming)

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By trackerj
#35247
spy king wrote:Any reason you did not consider using the ACS711 which supports a VCC of 3.3v?


I don't see ACS711 as a direct drop-in replacement for ACS712, datasheet quote: "The Allegro™ ACS711 provides economical and precise solutions for AC or DC current sensing in <100 V audio, communications systems, and white goods."

If your needs are covered by the ACS711 working domain, might be.
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By spy king
#35250
trackerj wrote:
spy king wrote:Any reason you did not consider using the ACS711 which supports a VCC of 3.3v?


I don't see ACS711 as a direct drop-in replacement for ACS712, datasheet quote: "The Allegro™ ACS711 provides economical and precise solutions for AC or DC current sensing in <100 V audio, communications systems, and white goods."

If your needs are covered by the ACS711 working domain, might be.


It does for me, I need to sense if a device is on (~1.7A) or in standby (~0.01A) @19v. Is this an overkill for this?
Surprising that the ACS711 is rather though to find at the local sources.
User avatar
By trackerj
#35263
spy king wrote:
trackerj wrote:
spy king wrote:Any reason you did not consider using the ACS711 which supports a VCC of 3.3v?


I don't see ACS711 as a direct drop-in replacement for ACS712, datasheet quote: "The Allegro™ ACS711 provides economical and precise solutions for AC or DC current sensing in <100 V audio, communications systems, and white goods."

If your needs are covered by the ACS711 working domain, might be.


It does for me, I need to sense if a device is on (~1.7A) or in standby (~0.01A) @19v. Is this an overkill for this?
Surprising that the ACS711 is rather though to find at the local sources.


ACS711 highest sensitivity version means +/- 12.5A ! You have about 110mV/A. In case of ACS712 you have +/- 5A at 185mV/A.

Also please keep in mind that the ACS711 is optimized for low-side current sensing applications.

I am not saying it will not work, actually give it a try and post feedback if you have time.

For something like your project request I will use a more "classical" approach with a a dedicated diff op amp for example, or a shunt monitor, depending on the accuracy that you want.
I will choose a shut resistor that will give me full-scale at 2A and that's it.

By the way, why do you want so "sense" the device ON/OFF only with current reading and not voltage if you are not interested to read precise the current for power calculation or something?

Talke also a look at the Battery Management System example, you have there both, voltage and current reading