Date: 23/05/2012

Programmable omnipolar Hall effect switch for proximity and position detection

Diodes Incorporated has announced a programmable omnipolar Hall effect switch AH1892 for proximity and position detection in space-constrained portable and battery-powered products, including tablets, smart phones and camcorders.

The switch is provided in the miniature 4-pin 0.7 x 0.7 x 0.5 mm U-WLB0707-4 package and is seventeen times smaller than the common 3-pin TSOT packaged alternatives, says the Manufacturer.

The switch is integrated with pull-up resistors that simplify the external circuit layout. A simple band select pin enables device sensitivity to be programmed to one of two predefined magnetic sensitivity ranges, allowing the device to be used in multiple applications with different field strengths. Sensitivity can also be adjusted on the fly via an external logic source such as a microcontroller, whereby band can be adjusted with a simple firmware upgrade.

The AH1892 operates at a supply voltage range of 1.6V to 3.6V. At normal operation the average current consumption is 4.3µA. The device provides protection against electrostatic discharge to a level of 8kV on supply and output pins. The device's operating temperature range is -40ºC to 85ºC.

The AH1892 is immune to the possibility of early or late switching effects. The device's chopper based design offers high resistance to RF noise and other circuit stresses.

The AH1892 is also offered in the standard low-profile SOT553 package.

A high-sensitivity version AH1894 will be made available later in the year which would be available in both SOT553 and DFN1216-4 package options.