Allegro MicroSystems, Inc. Announces New General Purpose Bipolar Switch

Offered in Multiple Packages with Improved Switching Repeatability

Worcester, MA – Allegro MicroSystems announces the release of a new bipolar switch designed with a high speed chopping circuit to null out offsets and dramatically improve switching repeatability. Allegro’s A1250 is an extremely temperature-stable and stress-resistant Hall-effect, bipolar switch. This device is especially suited for operation over extended temperature ranges to +150°C. Superior high temperature performance is made possible through dynamic offset cancellation, which reduces the residual offset voltage normally resulting from device overmolding, temperature dependencies, and thermal stress. This new device is targeted at the automotive, industrial and consumer markets.

The A1250 design includes on a single silicon chip a voltage regulator, Hall-voltage generator, small-signal amplifier, chopper stabilization, Schmitt trigger, and a short-circuit-protected, open-collector output. A south pole of sufficient strength will turn the output on. A north pole is necessary to turn the output off.

An on-board regulator permits operation with supply voltages of 3.0 to 24 V. The advantage of operating at 3.0 V is that it can be used in 3 V applications or additional external resistance can be added in series with the supply pin for greater protection in applications that can supply higher voltages.

Two package styles provide a magnetically optimized package for most applications. Package type LH is a modified SOT-23W surface mount package, while the UA package is a three-lead, ultra-mini-SIP for through-hole mounting. Each package type is only available as lead (Pb) free (suffix, -T), with a 100% matte tin plated lead frame.