Use two hall effect sensors mounted back-to-back? ________________________________________ From: piclist-bounces@mit.edu on behalf of mike b= rown Sent: Saturday, October 28, 2017 10:48 AM To: Microcontroller discussion list - Public. Subject: [EE] Picking omnipolar Hall effect sensors Hello all, I need some cheap, easily available Hall effect sensors that are switches, omnipolar and sensitive. I=92m doing a game room project and need to sense some magnets that are embedded within =93tiles=94 made from three pieces of thin plywood. The sensors will be under a table top approximately =BE=94 t= hick (18mm). I can carve away some of the wood to get the sensor near the surface. Normally I would use reed switches, but I just can=92t stand working with their frailty. The builder of the tiles can=92t be bothered with sorting the polarity of t= he neodymium magnets that are =BE=94 in diameter and about 3/32=94 thick. The= se are fairly powerful magnets that can activate a reed switch several inches away, but not reliably when centered precisely over the reed switch. I=92m guessing that has to do with the flux field being flattened by the large diameter and relative thinness of the magnets. I can get qty 10 A3144 sensors for under $5 including fast shipping, but these are unipolar. Is there another part number, in this price range, that would be at least as sensitive and in a omnipolar form? I don=92t wan= t latches or linear devices. --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .