ACS712 Current Sensor - Identification

There are two ICs in the Model: ACS712, which measure bidirectional current of upto 5A (AC(50kHz) & DC) -

ACS712-ELC-05B & ASC712T-ELC-05B.

The ACS712T is the original IC from Allegro, which i have confirmed with the Datasheets. The ACS712 without the "T", datasheets do not exist. Apparently, the breakout boards that are available in the 1000s are mixed. So if you are looking to accurately measure current within the range of upto 5A (both ways), please check the model of the IC that is being used. If the model is ACS712T, then the datasheet from allegro can be directly followed.

ACS712T (Original Allegro) - The Vout when 0 AMPS input, is not Vcc / 2. It usually is around 2.5V. In case the Vcc varies from 4.5 to 5 or 5 to 5.5, the Vout is constant at 2.5V. In the datasheet this offset voltage is mentioned "due to non-magnetic causes." The sensitivity is exactly 185mV / A, which means the actual current can be measured.

ACS712 - The Vout when 0 AMPS input, is exactly Vcc / 2. However the sensitivity is almost double (i calibrated to 330mV / A, in order to get a proper reading). Since the 0 AMPS reading is 1/2 the Vcc, the ADC Value (for 10 bit ADC) can be taken as 512 for 0 Amps.

Both the ICs are similar in measuring AC voltage (up to 240VAC).

Both the ICs are good enough at measuring DC / AC current. However the Zero Offset voltage is higher for the ACS712T. And the Sensitivity is higher for the ACS712 at almost double.

Please comment and let me know, if you have any difficulties / doubts with related to this IC.

Thanks.