Hall-effect sensors deliver high accuracy over time and temperature

By Gina Roos, editor-in-chief

Texas Instruments (TI) has claimed the industry’s first zero-drift Hall-effect current sensors that enable the lowest drift and highest accuracy over time and temperature. The TMCS1100  and TMCS1101  also provide 3-kVrms isolation, which is an important specification for AC or DC high-voltage systems such as industrial motor drives, solar inverters, energy-storage equipment, and power supplies.

Demand for precise current measurement and high reliability in industrial systems often comes at the price of increased board space or design complexity, said TI. However, with these new devices, the solution size remains compact without increasing design time and provides consistent performance and diagnostics over a longer device lifetime.

This is thanks in part to the zero-drift architecture and real-time sensitivity compensation of the TMCS1100 and TMCS1101, which enables high performance even under temperature changes and equipment aging. The devices provide total sensitivity drift over temperature of 0.45%, maximum, which is at least 200% lower than other magnetic current sensors, said TI, and a maximum full-scale offset drift of <0.1%. This translates into high measurement accuracy and reliability across a wide current range.

The devices also offer a 0.5% lifetime sensitivity drift, which is at least 100% lower than other magnetic current sensors, according to TI. This also helps reduce the performance degradation associated with system aging over time. Other key specs include high accuracy — 1% max for the TMCS1100 and 1.5% max for TMCS1101, which eliminates the need for device calibration, and typical linearity of 0.05%, which reduces signal distortion and helps maintain accuracy across the extended industrial temperature range of −40°C to 85°C.

Available now in eight-pin SOIC packages, the TMCS1100 and TMCS1101 support a ±600-V lifetime working voltage, which is up to 40% higher than competitive devices in the same package, said TI. Both devices have been tested beyond industry-standard UL and VDE requirements.

Pricing for both sensors starts at $1.50 in quantities of 1,000. Full- and custom-quantity reels are available on TI.com and through the distribution channel. The TMCS1100EVM  and TMCS1101EVM  evaluation modules (EVMs) are available for purchase on TI.com for $59 each.