I’ve been looking for a hall effect sensor to replace HAL740SF-K or HAL740SF-E which is obsolete now. We bought a huge stockpile when it went EOL but we will soon run out of them.
It was SOT89B, It was dual output (North and south), Its open drain, Unipolar (ie the pin will stay high as long as field is present and go low once removed), Threshold is 8 to 11mT or 80gauss to 110gauss and ran at 5V.
Ideally, I would like a pin to pin compatible replacement. If not I like to find a replacement thats at least dual output, unipolar runs at 5V and about the same sensitivity.