Date: 09/11/2009

New Hall-effect sensor IC with high temperature stability

Allegro has introduced the A1222, a Hall-effect sensor IC that is used to detect the speed and direction of ring magnets for motor commutation.

The A1222 delivers a high-temperature performance through dynamic offset cancellation that reduces the residual offset voltage normally caused by device overmolding, temperature dependencies, and thermal stress. Each A1222 device includes on a single silicon chip: a voltage regulator, Hall-voltage generator, small-signal amplifier, chopper stabilization, Schmitt trigger, and short-circuit protected open-collector output that can sink up to 25 mA. An on-board regulator operates with an input voltage of 3.0 to 24 V. This device can be used in 3 V applications and additional external resistance can be added in series with the supply pin for greater protection against transient events.

Other key features of A1222 are,

Symmetrical latch switchpoints
Resistant to physical stress
Temperature stability
Output short-circuit protection
Operation from unregulated supply down to 3 V
Reverse battery protection
Solid-state reliability
Small package sizes

Operating temperature range: 150°C

Package: Two package styles
Package type LH is a modified SOT23W, surface mount package
The UA is a three-lead, ultra-mini-SIP for through-hole mounting
Each package type is available as lead (Pb) free (suffix, -T), with a 100% matte tin-plated lead frame.

For more details visit www.allegromicro.com