A1201, A1202, A1203, and A1204

A1201-DS, Rev. 2

Worcester, Massachusetts 01615-0036 (508) 853-5000

115 Northeast Cutoff, Box 15036

www.allegromicro.com

Allegro MicroSystems, Inc.

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ABSOLUTE MAXIMUM RATINGS

Magnetic Flux Density, B .........................Unlimited

Operating Temperature

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

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 packag-

ing, to ensure increased switchpoint accuracy by eliminating offsets that can be

induced by package stress. Unique Hall element geometries and low-offset ampli-

fiers 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 auto-

motive and motor commutation applications, without adding external components.

All devices in the family are identical, except for magnetic switchpoints.

The small geometries of the BiCMOS process allow these devices to be pro-

vided in ultrasmall packages. The package styles available provide magnetically

optimized solutions for most applications. Package LH is a SOT23W, a miniature

low-profile surface-mount package, while package UA is a three-lead ultramini

SIP for through-hole mounting. Each package is lead (Pb) free, with 100% matte

tin plated leadframes.

Continuous-Time Bipolar Switch Family

Features and Benefits

Package UA, 3-pin SIP

Package LH, 3-pin Surface Mount

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