This board is a simple carrier of Allegro’s ±15.5 A ACS711 Hall
effect-based linear current sensor with overcurrent fault output, which
offers a low-resistance (~0.6 mΩ) current path and electrical isolation
up to 100 V. This version accepts a bidirectional current input with a
magnitude up to 15.5 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.his current sensor is a carrier board or breakout board for Allegro’s
ACS711KEXLT-15AB-T Hall effect-based linear current sensor with
overcurrent fault output; we therefore recommend careful reading of the ACS711 datasheet
(533k pdf) before using this product. This sensor has an operating
voltage of 3 V to 5.5 V and an output sensitivity of 90 mV/A when Vcc is
3.3 V (or 136 mV/A when Vcc is 5 V). The following list details some
of the sensor’s key features:
- Designed for bidirectional input current from -15.5 A to 15.5 A
(though the robust sensor IC can tolerate 100 ms transient current
spikes up to 100 A).
- Conductive path internal resistance is typically 0.6 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
- 100 kHz bandwith.
- 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
- Overcurrent FAULT output latches low when current magnitude exceeds 15.5 A.
- Operating temperature range of -40°C to 125°C.