These Hall-effect switches are designed for magnetic actuation using a bipolar magnetic field, i.e., a north-south alternating field. They combine extreme magnetic sensitivity with excellent stability over varying temperature and supply voltage. The high sensitivity permits their use with multi-pole ring magnets over relatively large distances. Each device includes a voltage regulator, quadratic Hall voltage generator, temperature stability circuit, signal amplifier, Schmitt trigger, and open-collector output on a single silicon chip. The on-board regulator permits operation with supply voltages of 4.5 to 24 V. The switch output can sink up to 25 mA. With suitable output pull up, they can be used directly with bipolar or MOS logic circuits. The three package styles available provide a magnetically optimized package for most applications. Suffix ‘LT’ is a miniature SOT-89/TO-243AA transistor package for surface-mount applications; suffixes ‘U’, and ‘UA’ feature wire leads for through-hole mounting. Prefix ‘UGN’ devices are rated for continuous operation over the temperature range of -20°C to +85°C, prefix ‘UGS’ devices over an extended range of -40°C to +125°C, and prefix ‘UGL’ devices over the range of -40°C to +150°C.
The Allegro 3132 and 3133 series are ultra‑sensitive bipolar Hall‑effect switches that operate from 4.5 V to 24 V and can sink up to 25 mA. Each device includes a voltage regulator, Hall voltage generator, temperature‑stability circuit, amplifier, Schmitt trigger and open‑collector output on a single silicon chip.
The datasheet provides absolute maximum ratings, electrical and magnetic characteristics, package dimensions for LT, U and UA styles, and a selection guide with operating temperature ranges for the different prefixes (UGL, UGN, UGS).
| Supply Voltage (Operating) | 4.5 V to 24 V |
|---|---|
| Continuous Output Current | 25 mA |
| Operating Temperature Range (UGL) | -40 °C to +150 °C |
| Operating Temperature Range (UGN) | -20 °C to +85 °C |
| Operating Temperature Range (UGS) | -40 °C to +125 °C |
| Magnetic Operate Point Bop (3132) | 32 G |
| Hysteresis Bhys (typ) | 30 G |
They operate from 4.5 V up to 24 V.
The devices can continuously sink up to 25 mA.
UGL covers –40 °C to +150 °C, UGN covers –20 °C to +85 °C, and UGS covers –40 °C to +125 °C.