LA25-NP Closed-Loop Hall-Effect Current Sensor

LA25-NP Product Overview

The LA25-NP is an industrial-grade closed-loop compensated Hall-effect current sensor from LEM, designed for electronic measurement of DC, AC, pulsed, and mixed waveforms. It provides complete electrical isolation between the primary and secondary circuits. Ideal for replacing traditional shunt solutions, it is widely used in industrial control, power electronics, power management, and other critical applications. The LA25-NP is a proven solution for medium- and low-power bidirectional current detection.

As a global leader in current and voltage sensors, LEM’s LA series is well known for its high accuracy, wide temperature adaptability, and robust isolation performance. With its superior closed-loop technology and flexible measurement range, the LA25-NP offers engineers a precise, reliable, and safe solution for current sensing.

LA25-NP Key Features

High Accuracy ±0.5% – Drift-Free Closed-Loop Technology

Using closed-loop Hall-effect technology with an active feedback coil, the LA25-NP delivers >50% higher accuracy compared to open-loop sensors. Typical accuracy is ±0.5%, with linearity error below ±0.2% and overall error within 0.2%, ensuring every measurement is accurate and reliable.

Bidirectional Current Measurement – Seamless Positive/Negative Operation

Rated current 25A, measuring range -36A to +36A. The sensor can directly measure positive and negative current without additional circuitry – ideal for motor forward/reverse, battery charge/discharge, etc. This significantly simplifies system design and reduces hardware costs.

Response Time ≤1µs – Capture Transients Without Distortion

Bandwidth DC to 150kHz, response time only 1µs – fast enough to capture PWM waveforms and transient overcurrent events. Perfect for dynamic applications like inverters and switch-mode power supplies (SMPS), avoiding failures caused by response delay.

Overload Capability – Withstands 3× Rated Current

Supports short-term overload up to 3× the rated current, ensuring stable operation under abnormal conditions such as inrush current or grid fluctuations.

Selectable Current Ranges – One Sensor for Multiple Applications

Supports multiple ranges: 5A, 6A, 8A, 12A, and 25A. One sensor adapts to different power levels, reducing BOM variety and simplifying inventory management.

Wide Operating Temperature –40°C to +85°C – Reliable in Harsh Environments

Designed for -40°C to +85°C – withstands outdoor equipment, industrial workshops, and severe EMI environments. Low temperature drift ensures stable output even under extreme conditions.

High Isolation Voltage – Safe and Reliable

Isolation voltage 2.5kVrms, insulation resistance >1500MΩ. Effectively isolates primary high-voltage circuits from secondary control circuits, meeting industrial safety standards and ensuring long-term insulation reliability.

Easy to Use – Broad Compatibility

Through-hole PCB mounting, suitable for hand soldering or wave soldering. Compatible with small-to-medium batch production and prototyping. Supply voltage ±15V (±5%) – fully compatible with standard industrial power supplies, no extra conversion needed.

Eco-Friendly – RoHS Compliant

Maximum operating current only 10mA – very low power consumption. Fully RoHS compliant – a green solution for sustainable development.

Flame-Retardant Housing – Safe Operation

Insulated plastic housing meets UL 94-V0 flame rating, reducing fire risk and complying with industrial safety standards.

LA25-NP Technical Specifications

LA25-NP Applications

With its high performance, reliability, and flexible configuration, the LA25-NP is widely used in:

Industrial drives – AC variable speed drives, servo motor drives, DC motor static converters

Power management – Uninterruptible power supplies (UPS), switch-mode power supplies (SMPS), welding power supplies

Renewable energy & energy storage – Battery-powered equipment, BMS charge/discharge monitoring, renewable energy systems

Industrial automation – Inverter control, power protection devices, isolated grid current measurement

Automotive electronics – Onboard electronics, high-precision voltage regulation

Why Choose the LA25-NP?

When selecting a current sensor, the LA25-NP offers unique advantages:

vs. Shunt solutions – Non-contact Hall measurement means no insertion loss and no power dissipation. Ideal for high-precision current sensing. High isolation prevents damage to control circuits from primary-side faults.

vs. Open-loop sensors – Closed-loop compensation significantly improves accuracy and linearity, with minimal temperature drift. More stable and reliable over temperature and long-term operation.

vs. Competitors – 0.5% accuracy combined with 150kHz bandwidth and µs-level response time offers excellent overall performance in its class. LEM is a top-tier global brand, ensuring consistent quality, comprehensive documentation, and long-term availability.