Diodes' small, micropower Hall effect switches are compatible with low voltage chipsets

     Diodes introduces three new Hall-effect switches, AH1899A/B/S, that operate at low supply voltage and very low static current to extend battery life in mobile and portable devices. The AH1899A/B/S can be used to detect whether the covers and cases of portable electronic devices such as smartphones and tablets are open. It can also be used for proximity detection in digital cameras, game consoles and general non-contact switches.

     The three switching devices are suitable for supply voltages from 1.1V to 2.0V and seamlessly integrate with the new 1.2V application chipset for ease of use. The product's energy-efficient architecture reduces the average operating current at 1.2V to as low as 0.95µA. A built-in sleep clock system in the switching device helps to make the system as energy efficient as possible to extend the operating time of the battery-loaded device.

     The Omnipolar AH1899A/B/S can operate near N or S poles on the package surface. Using the Chopper Stabilized topology, the magnetic operating point (BOP) and release point (BRP) exhibit minimal drift characteristics at supply voltage and temperature. Two sensitivity level options give designers the flexibility to define switch response times for application designs. The AH1899B and AH1899S switches operate when the magnetic field strength (B) exceeds 30 gauss and are released when it is below 20 Gauss. AH1899A is a highly sensitive model, operating at 18 gauss magnetic field intensity and releasing at 12 Gauss magnetic field intensity. If the magnetic field strength is not sensed, all three models remain closed.

     The three switching devices are packaged as X2-DFN1010-4 (Type B) surface mount to help designers save board space. The device size is only 1.0mm x 1.0mm and the height is 0.4mm, which is smaller than other traditional devices. In addition, the internal circuit integrates pull-up and pull-down resistors to save PCB area normally required by external components.