Sensitive Two-Wire Field-Programmable

Chopper-Stabilized Unipolar Hall Effect Switches

A1180, A1181,

7

Allegro MicroSystems, Inc.

115 Northeast Cutoff, Box 15036

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

www.allegromicro.com

Functional Description

B+

B–

I+

0

(A) A1180 and A1182

B+

I+

B–

0

(B) A1181 and A1183

Operation

after the magnetic field at the Hall sensor exceeds the oper-

high. The differences between the magnetic operate and release

in hysteresis allows clean switching of the output even in the

presence of external mechanical vibration and electrical noise.

The A1181 and A1183 devices switch with opposite polarity for

A1183 (see figure 1).

Figure 1. Alternative switching behaviors are available in the A118x device family. On the horizontal axis, the B+ direction indicates

increasing south polarity magnetic field strength, and the B– direction indicates decreasing south polarity field strength (including the

case of increasing north polarity).