New Current Sensor ICs: Advancing High-Isolation Technology in Compact Packages

In today’s power-hungry world of electric vehicles, renewable energy systems, and industrial automation, accurately measuring current flow while maintaining electrical isolation is critical. The latest generation of integrated current sensor ICs is revolutionizing this field by offering unprecedented isolation capabilities in increasingly compact packages.

How Modern Integrated Current Sensors Work

Integrated Current Sensor ICs (ICS) represent the cutting edge of current measurement technology. Unlike traditional current sensing methods that rely on bulky ferrite cores, these modern sensors employ an innovative approach that integrates multiple components into a single package:

Current conductorthrough which the measured current flows
Hall-effect sensing elementsfor contactless current detection
Signal treatment diethat processes the raw measurements
Isolation barriersproviding galvanic separation between high and low voltage circuits
Additional featuressuch as overcurrent detection and fault protection

The key innovation in modern sensor ICs is the use of differential measurement techniques. By employing two Hall-effect sensing elements—one with a positive factor and one with a negative factor—these sensors can effectively measure the target current while canceling out external magnetic field interference without requiring a ferrite core.

Key Advantages of New Current Sensor IC Technology

Enhanced Isolation in Smaller Footprints

The latest current sensor ICs offer remarkable isolation capabilities despite their compact size. For example, LEM’s HMSR series provides guaranteed isolation of 4.95kV, with laboratory testing demonstrating performance up to 5.66kV. This is achieved through innovative pre-mold designs that isolate the primary conductor and special footprints allowing 8mm creepage and clearance distances on landing pads.

Space and Weight Reduction

Modern integrated current sensors significantly reduce the overall footprint of the current sensing function, making them ideal for space-constrained applications such as:

Electric vehicle inverters and battery management systems
Compact solar inverters
Industrial drives and robotics
E-mobility applications where weight and space are premium considerations

Improved Technical Performance

These new ICs deliver numerous performance enhancements:

Higher accuracy: Typically 1% at room temperature with low drift characteristics
Expanded temperature range: Not limited by ferrite core Curie temperatures
Improved frequency response: Without magnetic core saturation limitations
Lower power consumption: Advanced designs operate with as little as 17mA
Superior interference immunity: Integrated micro-cores and differential sensing technologies provide excellent external magnetic field immunity

Cost and Design Simplification

By integrating multiple functions into a single package, these sensors offer:

Reduced component count for current measurement functions
Simplified PCB layouts with built-in isolation
Decreased assembly complexity
Eliminated need for additional electronics that would be required with shunt-based alternatives

Leading Applications for Advanced Current Sensor ICs

Electric Vehicle Systems

New current sensor ICs are finding widespread adoption in electric vehicle applications, where they monitor:

Battery charging and discharging processes
Motor drive currents for propulsion systems
Power distribution throughout the vehicle
Fault detection and protection systems

The high isolation ratings are particularly valuable in EV applications, where working voltages continue to increase to 800V and beyond in newer vehicle architectures.

Renewable Energy Systems

In solar inverters and energy storage solutions, integrated current sensors provide:

DC side current monitoring with high isolation
Grid-connected inverter current control
Safety monitoring and rapid fault detection
Optimization of power conversion efficiency

Industrial Automation

Modern factories and automation systems benefit from these sensors in:

Variable frequency drives for motor control
Robot articulation and motion control
Power monitoring and energy efficiency systems
Predictive maintenance through accurate current measurement

Smart Grid and Power Distribution

The transition to smarter electrical grids is enabled by advanced sensors that offer:

High precision monitoring of power distribution
Integration with digital control systems
Enhanced safety through galvanic isolation
Compact installation in space-constrained equipment

Allegro MicroSystems has launched two new current sensor ICs — the ACS37030MY and the ACS37220MZ.

Leveraging cutting-edge sensing technology developed by Allegro, these current sensor ICs provide low internal conductor resistance, high operating bandwidth and reliable performance across a wide range of automotive, industrial and consumer applications.

“Our newest sensors establish new standards for precision and reliability, empowering customers to overcome design and efficiency standards, while also demonstrating how our technology is driving a smarter, more efficient future,” said Ram Sathappan, Vice President of Global Marketing and Applications at Allegro MicroSystems.

The current sensor ICs are designed for precise current sensing in a compact and durable package. Featuring a widebody design, the ACS37030MY and ACS37220MZ deliver higher isolation in a 40% smaller footprint compared to the existing 16-pin packages on the market. The new innovative designs also incorporate lower resistance, which helps to reduce power dissipation.

The ACS37030MY is a fully integrated current sensor IC with industry’s fastest response time for protection of wide bandgap GaN devices. It uses a combination of Hall-effect and inductive coil signal paths to sense current over a wide frequency range. This innovative package offering enables a product which is both 5x faster than existing offerings, but also 40% smaller. ACS37030 is also available in a narrow-body package for lower isolation requirements.

The ACS37220MZ fully-integrated, Hall-effect current sensor features a 150 kHz bandwidth and fault pin. This device is designed for value-line current sensing applications as a successor to the popular ACS724/5 family of products. The new package of the ACS37220MZ offers a 40% smaller size and lower resistance for lower power dissipation.

Future Trends in Current Sensor IC Development

The evolution of current sensor ICs continues with several promising directions:

Increasing Integration

Future sensors will likely integrate more functionality, including:

Advanced diagnostic capabilities
Digital interfaces for direct microcontroller connection
Programmable features for application-specific optimization
Temperature sensing and compensation

Higher Isolation with Smaller Sizes

Ongoing research focuses on:

Novel isolation materials and techniques
Improved manufacturing processes for higher voltage withstand
Further miniaturization while maintaining safety margins
3D packaging technologies for vertical integration

Enhanced Environmental Performance

Next-generation sensors will feature:

Wider operating temperature ranges
Improved vibration and shock resistance
Enhanced EMI/EMC immunity
Lower power consumption for energy-sensitive applications

Overall

The latest integrated current sensor ICs represent a significant advancement in electrical measurement technology, offering the perfect combination of high isolation, compact size, and excellent performance. As electronic systems continue to shrink while operating at higher voltages and currents, these sensors will play an increasingly critical role in ensuring efficient, safe, and reliable operation across numerous applications.

For designers seeking to optimize their next-generation power electronics, modern integrated current sensor ICs provide a compelling solution that balances technical performance, safety requirements, and space constraints—enabling the continued evolution of electric vehicles, renewable energy systems, and industrial automation.