Unipolar Hall switch with temperature-compensated thresholds
The DRV5021A2QDBZT is a unipolar Hall-effect switch from Texas Instruments, packaged in SOT-23-3 for surface-mount assembly. It responds only to a south-pole magnetic field, with a typical operate point of 12.5 mT and a release point of 3.6 mT — the 8.9 mT hysteresis prevents output chatter near the threshold. This matters for applications where the magnet's field strength drifts with temperature — the sensor's own drift is cancelled out.
2.5V supply, open-drain output, 30 mA sink
Supply voltage is fixed at 2.5 V, drawing 2.8 mA typical. The open-drain output sinks up to 30 mA — enough to drive a logic input or a small LED directly, but requiring a pull-up resistor to the host's logic rail. The output is active-low when a south pole exceeding 12.5 mT is present. In the unpowered or undetected state, the output goes high-impedance — the pull-up resistor defines the idle logic level.
Active lifecycle — no end-of-life concern
This is a current-production part suitable for both new designs and ongoing BOM replenishment.