Product Description
This board is a simple carrier of Allegro’s bidirectional ±50A ACS724LLCTR-50AB Hall effect-based linear current sensor, which offers a low-resistance (~1.2 m?) current path and electrical isolation up to 2.4 kV RMS. This version accepts a bidirectional current input with a magnitude up to 50 A and outputs a proportional analog voltage (40 mV/A) centered at 2.5 V with a typical error of ±0.8%. It operates from 4.5 V to 5.5 V and is intended for use in 5 V systems.
This current sensor is a carrier board or breakout board for Allegro’s ACS724LLCTR Hall effect-based linear current sensors; we therefore recommend careful reading of the ACS724 datasheet (2MB pdf) before using this product. The following list details some of the sensor’s key features:
- Differential Hall sensing rejects common-mode fields, so the orientation of the sensor relative to uniform external magnetic fields (e.g. the Earth’s magnetic field) does not affect the measurement.
- The conductive path internal resistance is typically 1.2 m?, and the PCB is made with 2-oz copper, so very little power is lost in the module.
- Use of a Hall effect sensor means the IC is able to electrically isolate the current path from the sensor’s electronics (up to 2.4 kV RMS), which allows the sensor to be inserted anywhere along the current path and to be used in applications that require electrical isolation.
- High 120 kHz bandwidth for faster response times in control applications.
- Optional FILTER pin simplifies bandwidth limiting for better noise reduction and improved resolution at lower frequencies.
- Integrated digital temperature compensation circuitry allows for near closed loop accuracy over temperature in an open loop sensor.
- Automotive-grade operating temperature range of -40°C to 150°C.
The pads are labeled on the bottom silkscreen, as shown in the picture to the right. The silkscreen also shows the direction that is interpreted as positive current flow via the +i arrow.
This carrier features the ACS724LLCTR-50AB, which operates at 5 V and is designed for bidirectional input current from -50 A to +50 A. When Vcc is 5 V, the output voltage is centered at 2.5 V and changes by 40 mV per amp of input current, with positive current increasing the output voltage and negative current decreasing the output voltage.
This board ships assembled with all surface mount components, and a 3×1 strip of 0.1? header pins is included but not soldered in.
Dimensions
- Size: 0.7" x 0.8"
- Weight: 1.1 g
General specifications
- Current sense: 0.040 V/A. When Vcc is 5 V.
- Minimum logic voltage: 4.5 V
- Maximum logic voltage: 5.5 V
- Supply current: 14 mA. Max. 10 mA typical.
- Version: -50A to +50A (bidirectional 50A)
- Current sensor: Allegro ACS724LLCTR-50AB
