Exclusive: ROHM claims the smallest contactless current sensor

It achieves minimum power loss (no heat generation) in an ultra-compact size, making it ideal for industrial equipment and consumer devices that detect operating conditions via current, including battery-driven drones, solar power systems, and servers in data centers requiring high power.

In recent years, the growing worldwide awareness of energy conservation and safety together with environmental regulations require improved safety measures and power measurement in high power applications such as servers in data centers and solar power systems.

This results in an increased demand for current sensors. However, conventional current sensors using hall elements typically feature large current consumption and low sensitivity, making it necessary to draw current within the sensing element itself. As such until now there were no current sensors on the market that provided high reliability and low loss in a compact form factor (3.5mm2).

ROHM has developed a current sensor utilizing a high sensitivity low current MI element that allows for completely contactless current detection. The BM14270MUV-LB was developed by combining ROHMs semiconductor production and sensor control technologies with Aichi Steel’s MI (Magneto-Impedance) element. The result is a contactless current sensor that eliminates the need to draw current within the sensor to measure it.

The sensor itself consumes very low current (0.07mA 100x smaller than conventional products) and comes in the industry’s smallest size (3.5mm2). In addition, a disturbance magnetic field cancellation function is included to protect against noise, making shielding unnecessary. Digital output from the built-in A/D converter reduces MCU load, facilitating easy current monitoring.

These features allow users to detect the current of virtually any application with high reliability, from compact battery-driven devices to high power industrial equipment

Availability: January 2019 (samples), April 2019 (OEM quantities)