In ipXchange’s second demo from Alps Alpine’s stand at PCIM, we chat with Christoph Geue as he demonstrates Alps Alpine’s high-precision magnetic sensors in a remote current sensing application. By placing the magnetic sensors close to the power cord of a hair dryer, Christoph shows that the current draw can be sensed for the various operating modes of the device, external to the circuitry of the system and without a flux concentrator, i.e., a big blog of magnetic yoking material.
Of course, this is simply a demo for the show, but the target applications for this sort of functionality using Alps Alpine’s devices include automotive traction inverters and battery management systems. Available in several compact packages – including the 3.0 x 4.9 x 1.1 mm TSSOP8-type package featured in the demo – the HGAR-series magnetic sensors feature a measurement range of up to 10-120 mT, with a typical current consumption of 5 mA, depending on the model.
Christoph then shows us an example of a typical evaluation setup, which is provided to customers in the form of some small boards with the sensor mounted in place and cables for easy connection to test equipment. He also reminds us that these sensors are magnetically sensitive in one direction, hence their primary use as a magnetic angle sensor for applications that include robotics and drones, virtual/augmented reality gaming HMIs, healthcare equipment, home/office appliances, and building automation. This evaluation setup supports sensing measurements up to 78 mT using GMR (Giant Magneto-Resistance) effects with around 2% error, but Alps Alpine’s other setups, which support measurement using TMR (Tunnel Magneto-Resistance) effects, can deliver engineers high-precision magnetic field measurements with <1% error, perfect for automotive battery management systems.