These parts are in production but have been determined to be LAST TIME BUY. This classification indicates that the product is obsolete and notice has been given. Sale of this device is currently restricted to existing customer applications. The device should not be purchased for new design applications because of obsolescence in the near future. Samples are no longer available. Date of status change: May 4, 2009.
Deadline for receipt of LAST TIME BUY orders: November 4, 2009. For existing customer transition, and for new customers or new applications, refer to the A1233.
The A3422xKA Hall-effect, direction-detection sensor IC is a new generation of special function integrated devices that are capable of sensing the direction of rotation of a ring magnet. These transducers provide separate digital outputs that provide information on magnet rotation speed, direction, and magnet pole count. This device eliminates the major manufacturing hurdles encountered in fine-pitch direction-detection applications, namely maintaining accurate mechanical location between the two active Hall elements. Here, the two Hall elements are photolithographically aligned to better than 1 µm, as contrasted with 100 µm or worse mechanical location tolerance when manufactured discretely. These highly sensitive, temperature-stable, magnetic transducers are ideal for use in digital-encoder systems in the harsh environments of automotive or industrial applications. The A3422xKA is a high-sensitivity device optimized for use with high-density magnets.
The A3422xKA monolithic integrated circuit contains two independent Hall-effect latches whose digital outputs are internally coupled to CMOS logic circuitry that decodes signal speed and direction. Extremely low-drift BiCMOS circuitry is used for the amplifiers to ensure symmetry between the two latches so that signal quadrature can be maintained. An on-chip voltage regulator allows the use of these devices from a 4.5 to 18 V supply. This device has standard open-collector outputs.