HBCT 250-V , HBCT250-V

HBCT 250-V Open-Loop Hall Effect Automotive Current Sensor

HBCT 250-V Product Overview

The HBCT 250-V is an open-loop Hall effect current sensor from LEM's HBCT series, specifically designed for automotive battery management systems . It provides to an engine control unit (ECU) the actual value of current flowing in and out of the battery, along with ambient temperature via an integrated NTC thermistor . The current measurement is performed with full galvanic isolation between the primary circuit (high power) and the secondary circuit (electronic circuit) .

The sensor features a battery clamp mounting design and connects to the ECU via a waterproof connector . The unipolar +5 V DC supply and ferrite material magnetic core allow high-frequency primary current ripple with low self-heating .

HBCT 250-V Key Specifications

Primary current, measuring range (IPM): −250 A to +100 A 
Nominal supply voltage (UC): 5 V (4.5 to 5.5 V) 
Output voltage: Full ratiometric (sensitivity and offset) 
Sensitivity (S): 11.43 mV/A 
Accuracy (Total error): 2% 
Linearity error (εL): ±1% 
Delay time to 90% (tD90): 1 ms 
Frequency bandwidth: 257 Hz 
Offset voltage (UO): 3.357 V 
Current consumption (IC): 8 to 10 mA 
Ambient operating temperature (TA): -30°C to +90°C 
Ambient storage temperature (TAst): -40°C to +125°C 
Insulation test voltage (Ud): 2.5 kV 
NTC Resistance (RNTC): 10 kΩ (accuracy of 1% at 25°C) 
Mounting: Battery clamp 
Package: Screw mount 

HBCT 250-V Key Advantages

The HBCT 250-V features excellent accuracy with ±0.6% sensitivity error and a total error of 2% over the full operating temperature range . The ferrite core material allows high-frequency primary current ripple while maintaining very low thermal offset and sensitivity drift . The fully ratiometric output (both sensitivity and offset) simplifies integration with ECU ADC inputs .

The integrated NTC thermistor provides battery temperature monitoring without additional sensors . The sensor offers high immunity to external interference, no insertion losses, and a very fast delay time of 1 ms . The waterproof connector and robust battery clamp mounting ensure reliable performance in demanding automotive under-hood environments .

HBCT 250-V Typical Applications

Automotive battery current monitoring for engine control units
Battery Management Systems (BMS) for hybrid and electric vehicles
Monitoring current flow in and out of the battery with temperature sensing
Low-voltage automotive applications requiring high-current measurement
Battery pole current and temperature monitoring

HBCT 250-V Why Choose the HBCT 250-V?

The HBCT 250-V combines a −250 A to +100 A measuring range, ±0.6% sensitivity error, and integrated temperature sensing in a robust automotive-grade package optimized for battery management applications. Manufactured by LEM, a global leader in electrical measurement, it delivers reliable, accurate current and temperature sensing specifically engineered for automotive battery systems . The open-loop Hall effect technology with ferrite core provides high immunity to external interference and low self-heating, while the battery clamp mounting and waterproof connector simplify installation. The integrated NTC thermistor provides comprehensive battery monitoring in a single package, making it the preferred choice for automotive engineers designing ECU-based battery management systems where precision, reliability, and temperature compensation are critical. The product is active and available for new designs.