Hall-effect technology, sensing to be exact, is not particularly novel, but is highly effective for a range of established applications. However, the IoT and other 21st Century apps require more functionality, reliability, and efficiency. Silicon Labs heeds the call by bringing Hall-effect sensing up to date with a modernized magnetic sensor portfolio.
The Si72xx series consists of the Si720x, Si721x, and Si7210 families. Collectively, they promise impressive power efficiency, best-in-class sensitivity, flexible I2C configuration, and integral tamper detection and temperature sensing. Of note, for auto manufacturers and OEMs, the sensors are AEC-Q100-qualified for automotive applications and can withstand tough-and-tumble industrial environments.
In terms of low power and efficiency, the sensors consume 100 nA of sleep current and less than 400 nA at a 5-Hz sampling rate. This can help designers achieve multiyear and decade-long battery lifetimes using standard and very small batteries. Additionally, the Si72xx sensors are easily configured, measured, and controlled over an I2C interface.
A really nice feature is a tamper threshold that enables systems to detect attempts to bypass security. Most reed switch and Hall-effect sensor-based security systems can be defeated by a strong external magnetic field. The tamper detection technology detects anomalous magnetic fields, and a self-test mode can be used to verify the sensor’s continued accurate operation in the field. The sensors also include a ±1°C accurate temperature sensor, eliminating the need for discrete temperature sensing. More details about the Si720x, Si721x, and Si7210 families are available from Silicon Labs.