Dual element devices are integrated circuits that contain two independent Hall-effect switches. The digital outputs are out of phase so that the outputs are in quadrature when interfaced with the proper ring magnet design (alternating pole ring magnet). This allows either the user to externally process the output signals to determine speed and direction of an encoder ring magnet or certain devices to internally process these signals and output speed and direction signals. Extremely low-drift amplifiers guarantee symmetry between the switches to maintain signal quadrature. The Allegro patented, high-frequency chopper-stabilization technique cancels offsets in each channel providing stable operation over the full specified temperature and voltage ranges.
The high-frequency chopping circuits allow an increased analog signal-to-noise ratio at the input of the digital comparators internal to the IC. As a result, the A1230 achieves industry-leading digital output jitter performance that is critical in high performance motor commutation applications.