A1221

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. Each device includes 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 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 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 is available as lead (Pb) free (suffix, ), with a 100% matte tin plated lead frame.