Dual element devices are integrated circuits that contain two independent Hall-effect switches. The digital outputs are out-of-phase (quadrature) when interfaced with the proper ring magnet design.
Allegro Vertical Hall-Effect Technology (AVHT) has been combined with traditional planar Hall-effect technology to create devices that have the ability to sense in two dimensions on a single wafer. Two dimensional technology allows quadrature signals to be detected on a single die, independent of ring magnet spacing.
Allegro's A1262 and APS12626 output these quadrature signals for further processing to determine target speed and direction. Alternately, the APS12626 can internally process these switch outputs into speed and direction signals.
Extremely low-drift amplifiers guarantee symmetry between the switches to maintain signal quadrature. The Allegro high-frequency, chopper stabilization technique cancels offsets in each channel, providing stable operation over the full specified temperature and voltage ranges, and industry-leading digital output jitter performance that is critical in high-performance motor commutation applications.
The following dual-element switches have been discontinued: A3423