This board carries the Allegro's ACS711ELCTR-12B-T hall effect-based linear current sensor, which offers a low-resistance (~1.2mΩ) current path.
The sensor operates at 3.3V (up to 5V) and its analog voltage output has a sensitivity of 110mV/A centered at 1.65V (if powered at 3.3V) with a typical error of ±1% and a 100kHz bandwidth.
Optimized bidirectional current range is from -12.5A to +12.5A, but its robustness allows survival of the device at up to 5× overcurrent conditions. Top silkscreen shows the direction that is interpreted as positive current flow.
The FLT pin trips when measured current reaches ±100% of its full-scale. It is an open-drain pin so it is necessary use an external pull-up resistor. Its value is active low.
||+3.3V to +5V
||4mA typ. (5.5mA max.)
||from -12.5A to +12.5A
|Typical output error
||-40°C / +85°C
||1.1” x 0.8”(27.9 x 20.3 mm)
||0.12 oz (3.5 g)