Board Mount Current Sensors For New Designs Use ACS72981

ACS781LLRTR-100B-T – 100A Bidirectional Current Sensor – Allegro MicroSystems

Precisely monitor AC/DC currents up to 100A with the ACS781LLRTR-100B-T Hall Effect current sensor from Allegro MicroSystems. This automotive-grade IC delivers ±1.5% accuracy with rapid 3.6μs response time, ideal for demanding power management applications. PCX guarantees genuine Allegro components with same-day shipping and dedicated technical support.

Key Features

• Current Range: ±100A bidirectional sensing
• High Accuracy: ±1.5% error tolerance at 25°C
• Response Time: 3.6μs ultra-fast detection
• Voltage Output: Ratiometric 13.2mV/A sensitivity
• Wide Bandwidth: DC to 120kHz frequency range
• Automotive Rated: AEC-Q100 qualified, -40°C to 150°C operation
• Low Power: 3V–3.6V supply, 15mA max current draw

Technical Specifications

This Hall Effect differential sensor features galvanic isolation via magnetic field measurement, eliminating shunt resistors. The surface-mountable 7-PSOF package provides integrated conductor termination. With ±1% linearity and ratiometric voltage output, it maintains accuracy across varying supply conditions. Bidirectional polarization allows current monitoring in both directions.

Typical Applications

• Electric vehicle battery management systems (BMS)
• Industrial motor control and overload protection
• Solar inverter current monitoring
• Server/telecom power supply units
• Appliance load detection circuits

About Allegro MicroSystems

Allegro MicroSystems is a global leader in power sensing and semiconductor solutions, specializing in high-performance ICs for automotive and industrial markets. With over 30 years of innovation, Allegro’s Hall Effect sensors set industry benchmarks for reliability and precision.

The company maintains rigorous AEC-Q100 qualification processes and IATF 16949 certification, ensuring components meet stringent automotive durability requirements. Allegro’s patented packaging technologies enable robust performance in high-vibration and extreme-temperature environments.

About Current Sensors

Current sensors are critical for real-time power monitoring and system protection in electronic designs. Unlike shunt resistors, Hall Effect sensors provide non-contact measurement, eliminating power loss and enabling high-voltage isolation. This makes them essential for safety-critical applications and energy-efficient systems.

Modern current sensors like the ACS781 series integrate signal conditioning, temperature compensation, and fault detection. Their compact form factors simplify PCB layout while providing calibrated outputs directly compatible with microcontrollers and ADCs, reducing development time and BOM complexity.

Packaging Options

Available in Tape & Reel (TR), Cut Tape (CT), and Digi-Reel® formats for automated assembly. Specify packaging preference at checkout.

Frequently Asked Questions

Q: Is this IC suitable for automotive applications?
A: Yes, it’s AEC-Q100 qualified and operates from -40°C to 150°C, meeting automotive reliability standards.

Q: Can it measure AC currents?
A: Absolutely. The 120kHz bandwidth supports both AC and DC current measurement up to 100A peak.

Q: What’s the advantage of ratiometric output?
A: Output voltage scales with supply voltage, maintaining accuracy even with power fluctuations.

Q: Does PCX provide datasheets?
A: Yes, download the full ACS781LLRTR-100B-T datasheet from our product page.

Q: How does Hall Effect sensing differ from shunt resistors?
A: Hall sensors use magnetic fields for contactless measurement, eliminating power loss and providing inherent isolation.

Q: Is calibration required?
A: No, factory-calibrated sensitivity and quiescent output minimize setup requirements.

Order your ACS781LLRTR-100B-T today for immediate shipment! PCX guarantees authentic Allegro components with lightning-fast delivery – contact our engineering support team for design assistance.