This board is a simple carrier of Allegro’s ±25A ACS711 Hall effect-based linear current sensor with overcurrent fault output, which offers a low-resistance (~1.2 mΩ) current path and electrical isolation up to 100 V. This version accepts a bidirectional current input with a magnitude up to 25 A and outputs a proportional analog voltage centered at Vcc/2 with a typical error of ±5%. It operates from 3 V to 5.5 V, so it can interface directly to both 3.3 V and 5 V systems.
This current sensor is a carrier board or breakout board for Allegro’s ACS711KLCTR-25AB-T Hall effect-based linear current sensor with overcurrent fault output; The sensor has an operating voltage of 3 V to 5.5 V and an output sensitivity of 55 mV/A when Vcc is 3.3 V (or 83 mV/A when Vcc is 5 V). The following list details some of the sensor’s key features:
Designed for bidirectional input current from -25 A to 25 A (though the robust sensor IC can survive up to five times the overcurrent condition).
Conductive path internal resistance is typically 1.2 mΩ, and the PCB is made with 2-oz copper, so very little power is lost in the board.
Use of a Hall effect sensor means the IC is able to electrically isolate the current path from the sensor’s electronics (for applications up to 100 V), which allows the sensor to be inserted anywhere along the current path and to be used in applications that require electrical isolation.
100 kHz bandwidth.
Good accuracy and reliability: factory calibration results in a typical total output error of ±5% at room temperature, the output offset voltage is extremely stable, and the sensor has zero magnetic hysteresis.
Overcurrent FAULT output latches low when current exceeds ± 25 A.