ALLEGRO ACS71240LLCBTR-010B3

The Allegro™ ACS71240 current sensor IC is an economical and precise solution for AC or DC current sensing in industrial, automotive, commercial, and communications applications. The device consists of a precise, low-offset linear Hall sensor circuit with a copper conduction path located near the surface of the die. Applied current flowing through this copper path generates a magnetic field which is sensed by the integrated Hall IC and converted into a proportional voltage. The resistance of the integrated conductor is far less than typical sense resistors, which reduces power loss and improves efficiency. Rejection of external common-mode magnetic fields is achieved through differential sensing, enabling high accuracy in magnetically noisy environments. A precise voltage proportional to the measured current is generated by the lowoffset, chopper-stabilized Hall front end. Zero ampere output voltage and device sensitivity are programmed at the Allegro factory to provide a high accuracy solution across the full automotive temperature range. The ACS71240 includes an integrated fault comparator for simplified overcurrent detection. The ultrafast response time provides the system with ample time to detect and protect against short-circuit events. The ACS71240 is provided in small, low-profile surface-mount package options: QFN-12 with wettable flank and SOIC-8. The leadframe is plated with 100% matte tin, which is compatible with standard lead (Pb) free printed circuit board assembly processes. Internally, the device is Pb -free, except for flipchip high-temperature Pb.-based solder balls, currently exempt from RoHS. The device is fully calibrated prior to shipment from the factory.

• AEC-Q100 automotive qualified
• Differential Hall sensing rejects common-mode fields
• Integrated shield virtually eliminates capacitive coupling from current conductor to die, greatly suppressing output noise due to high dv/dt transients
• Industry-leading noise performance with greatly improved bandwidth through proprietary amplifier and filter design techniques
• High bandwidth 120 kHz analog output for faster response times in control applications
• Patented integrated digital temperature compensation circuitry allows for near closed-loop accuracy over temperature in an open loop sensor
• Single supply operation with nonratiometric output at 3.3 and 5 V options
• Overcurrent FAULT available between 50% and 200% IP with 1.5 μs (typ) response time
• Non-ratiometric output provides immunity to noisy supplies
• Small footprint QFN-12 with wettable flank and SOIC-8 suitable for space-constrained automotive applications
• 0.6 mΩ (QFN-12) or 1.2 mΩ (SOIC-8) primary conductor resistance for low power loss and high inrush current withstand capability
• UL certified package (SOIC-8 only) for voltage isolation

• industrial
• automotive
• commercial
• communications