UGN-3020T

The UGN-3020T has the following features including 4.5 V to 24 V Operation;Magnetically Driven Output;High Reliability-No Moving Parts;Small Size;Output Compatible with All Digital Logic Families;Constant Output Amplitude.

OFFERING HIGHLY RESPONSIVE magnetic characteristics and fast, trouble-free switching at moderate cost, Type 3020 Hall Effect integrated circuits represent middle ground between less sensitive devices and those demanding premium prices.The magnetically activated electronic devices are available with two operating temperature ranges and in two three-pin plastic packages.Each Hall Effect circuit includes a voltage regulator, Hall voltage generator, signal amplifier,Schmitt trigger, and open-collector output on a single silicon chip. The on-board regulator permits operation over the supply-voltage range of 4.5 to 24 V. The switches' open-collector outputs can sink up to 20 mA at a conservatively rated repetition rate of 100 kHz. They can he used directly with bipolar or MOS logic circuits. Selected devices, with out-puts capable of sinking 50 mA, are available on special order.

The most common modes of operation are head-on and slide-by. As shown in the drawing at right,the magnet's polar axis is the centerline of the Hall Effect package. Change of operating states in the head-on mode is accomplished by decreasing or increasing the distance between the magnet and Hall cell.The output transistor is OFF when the flux density of the magnetic field perpendicular to the surface of the chip is below threshold (the operate point).When Hux density reaches the operate point, the output transistor switches ON and is capable of sinking 25 mA of current.A wide variety of magnets is commercially available. Each type of magnet exhibits unique magnetic field characteristics. The magnets used to construct the Flux Density graph were measured for the head-on mode of operation, but the graph's information is valid for peak flux density in the slide-by mode of switch activation.Total effective air gap is the sum of active area depth and the distance between the package's surface and the magnet's surface. The graph of Flux Density as a Function of Effective Air Gap illustrates the considerable increase in flux density at the sensor provided by the thinner package. The actual gain depends on the characteristic slope of flux density for a particular magnet.