The A3423 dual-channel Hall-effect sensor from Allegro Microsystems Inc. provides output signals that indicate speed and direction in direction-sensing applications involving encoder-ring magnet targets. The Hall elements are both photo-lithographically aligned to better than 1 µm. Maintaining accurate mechanical location between the two active Hall elements eliminates the major manufacturing hurdle encountered in fine-pitch detection applications. The highly sensitive and temperature-stable device suits use in harsh automotive and industrial environments.
The Hall elements are spaced 1.63 mm apart, which ensures excellent speed and direction information for small-geometry targets. Extremely low-drift amplifiers guarantee symmetry between the switches to maintain signal quadrature. An on-chip regulator allows the A3423 to operate over a wide voltage range of 3.8 to 24.0 V. End-of-line trimming of the Hall element switch points provides for tight matching capability. The continuous-time method of offset cancellation delivers fast startup and signal recognition as well as very low noise on the output.
The A3423 costs $1.78 in quantities of 1000 and has a 14-week lead-time. For more information, go to http://vocuspr.vocus.com/VocusPR30/Url.aspx?516867x1046x459623.