Diodes Incorporated has unveiled two low voltage Omnipolar switches that reduce power consumption in battery-powered, hand-held devices and also simplify production processes.
The devices are suitable for use in contact-less lid or display orientation and position detection tasks employed by notebooks, mobile phones, digital still cameras and camcorders.
Operating over a wide supply voltage range, the micro-power AH1802 and AH1888 Hall effect sensor switches support a broad range of battery cell configurations, from single cell Lithium Ion to dual cell alkaline/zinc. As an illustration of its low power operation, the AH1888 consumes just 15 micro-watts for a supply voltage of 1.8 V.
The AH1802 and AH1888 detect the magnetic field generated by both North and South poles, thereby removing the requirement for production processes to manage magnet orientation. In the presence of a local magnetic field, the sensor produces a low level 'on' output signal.
The AH1802 with an open drain, single output offers high sensitivity that makes it ideal for sensing vertically oriented or smaller sized magnets. Packaged in an ultra thin 0.4 mm height DFN2015, the compact AH1802 fits slider style mobile phones where height is critical. Offered in the low profile SOT-553 package, the AH1888's dual complementary push-pull outputs enable the device to be directly connected to a system processor without the use of pull up resistors. Outputs adjust to polarity changes, allowing the device to support key wheel type magnets, which are used to detect position and orientation for displays or keyboards that pivot or rotate.
The sensors' chopper stabilization circuitry delivers superior temperature stability, making them less sensitive to physical stress and guards against switch-point drift. Both devices support an operating temperature range from -40 to 85 degrees C.
The AH1802 is priced at $0.30USD in 1K quantities and the AH1888 at $0.35USD in 1K quantities.