LED Driver with Hall Effect Switch

Allegro MicroSystems, LLC rolled out the world’s first LED driver IC that features an integrated Hall-effect switch. The A1569 enables compact, elegant, reliable, and fault-tolerant LED lighting with minimal electrical engineering and low component-count and cost. A single silicon chip integrates: a Hall plate, a small-signal amplifier, chopper stabilization, a Schmitt trigger, and a LED driver with soft on/off and short circuit and thermal protection with automatic recovery. The integrated solid-state Hall-effect switch supports silent, sealed, contactless activation and offers a significant upgrade from failure-prone mechanical switches.

The LED driver features low-noise, adjustable, linear drive of up to 150 mA into one or more LEDs. An optional external capacitor programs the turn-on/turn-off rate, adding an elegant “theater” effect. It is controlled by the Hall-effect switch and turns on and off in response to a magnet. The Hall-effect switch is omnipolar (responsive to both North and South magnetic poles) and highly sensitive (BOP = 40 G) to support a wide range of mechanical configurations and enclosures with various air gaps and degrees of mechanical misalignment.