Features and Benefits

▪ Continuous-time operation

▫ Fast power-on time

▫ Low noise

▪ Stable operation over full operating temperature range

▪ Reverse battery protection

▪ Solid-state reliability

▪ Factory-programmed at end-of-line for optimum

performance

▪ Robust EMC performance

▪ High ESD rating

▪ Regulator stability without a bypass capacitor

Description

The Allegro® A1201, A1202, A1203, and A1204 Hall-effect

bipolar switches are next-generation replacements and

extension of the popular Allegro A3134, A3133, and A3132

bipolar switch product line. Overall, the A120x family, produced

with BiCMOS technology, consists of continuous-time devices

that feature fast power-on time and low-noise operation. Device

programming is performed after packaging, to ensure increased

switchpoint accuracy by eliminating offsets that can be induced

by package stress. Unique Hall element geometries and lowoffset

amplifiers help to minimize noise and to reduce the

residual offset voltage normally caused by device overmolding,

temperature excursions, and thermal stress.

The A120x Hall-effect bipolar switches include the following on

a single silicon chip: voltage regulator, Hall-voltage generator,

small-signal amplifier, Schmitt trigger, and NMOS output

transistor. The integrated voltage regulator permits operation

from 3.8 to 24 V. The extensive on-board protection circuitry

makes possible a ±30 V absolute maximum voltage rating for

superior protection in automotive and motor commutation