Low-voltage omnipolar Hall switch for battery-operated position sensing
The TMAG5231H1DQDMRR is a low-power, low-voltage omnipolar Hall-effect switch from Texas Instruments. It detects the presence of either a north or south magnetic pole, making it suitable for lid-closure detection, proximity sensing, and contactless switch applications in portable and battery-powered devices. Operating from a supply voltage as low as 1.65 V, this sensor can run directly from a single alkaline or lithium coin cell without a boost converter. The push-pull output eliminates the external pull-up resistor, saving board space and reducing BOM count.
Magnetic thresholds and temperature range for reliable switching
The device switches at a typical magnetic flux density of ±50 mT (trip point) and releases at ±23.5 mT, providing a hysteresis window of approximately 26.5 mT. This hysteresis prevents output chatter when the magnet is near the threshold. The magnetic thresholds are specified at 25°C; temperature drift of the Hall plate will shift these values across the full range. The Sleep Mode feature (listed in the feature set) indicates the part enters a low-power state between sampling cycles, drawing minimal quiescent current. This makes it viable for always-on sensing in battery-powered designs where every microamp matters.