Allegro Microsystems Offers A3250/A3251 Switches

Allegro MicroSystems Inc. (Worcester, MA) announced the release of the first family of programmable uni-polar Hall-effect switches. These devices are one-time externally programmable over a wide magnetic operating range. The feature of external programming allows the user to optimize the magnetic switch points in order to reduce the effects of offsets, which can be caused by package and magnet placement tolerances.

Allegro’s A3250 and A3251 are ideal for both automotive and industrial proximity sensing applications that require tight part-to-part distribution. Both devices are equipped with on-chip protection for supply transients, output short-circuiting and reverse battery. The switches are temperature-stable (low switch point drift over temperature) and stress resistant. The A3250 and A3251 differ from each other only in output polarity; the A3250 output current goes low in the presence of a south pole of sufficient strength; the A3251 output current goes high.

Allegro’s programmable A3250 and A3251 Hall-effect switches are currently available in the three-lead single in-line package (UA package) and are offered in two operating temperature ranges, “J” = -40 to +115 degrees C and “L” = -40 to +150 degrees C. The A3250JUA and A3251JUA devices are priced at $0.91 per part for quantities of 1,000, and the A3250LUA and A3251LUA devices are priced at $1.24 per part for quantities of 1,000. All devices have a four-to-six week lead-time to market.