A1221

• Symmetrical latch switch points
• Resistant to physical stress
• Superior temperature stability
• Output short-circuit protection
• Operation from unregulated supply down to 3 V
• Reverse battery protection
• Solid-state reliability
• Small package sizes

Description

The A1220 and A1221 Hall-effect sensors are extremely temperature-stable and stress-resistant sensors especially suited for operation over extended temperature ranges to +150°C. Superior high-temperature performance is made possible through dynamic offset cancellation, which reduces the residual offset voltage normally caused by device overmolding, temperature dependencies, and thermal stress. A1220 and A1221 include on a single silicon chip a voltage regulator, Hall-voltage generator, small-signal amplifier, chopper stabilization, Schmitt trigger, and a short-circuit protected open-collector output to sink up to 25 mA. A south pole of sufficient strength will turn the output on. A north pole is necessary to turn the output off.

An on-board regulator permits operation of A1220 and A1221 with supply voltages of 3 to 24 V. The advantage of operating at 3 V is that it can be used in 3 V applications or additional external resistance can be added in series with the supply pin for greater protection in applications that can supply higher voltages.

Two package styles of A1220 and A1221 provide a magnetically optimized package for most applications. Package type LH is a modified SOT23W surface mount package while UA is a three-lead ultra-mini-SIP for through-hole mounting. Each package type of A1220 and A1221 is available as lead (Pb) free (suffix), with a 100% matte tin plated lead frame.