www.austrimaicrosystems.com revision 0.1 1 - 6 1 general this specification defines the dimensional and magn etic properties of a multipole magnetic strip for u se with the as5306 magnetic linear motion and off-axis rotary a ngle encoder. material: strontium ferrite bonded 2 dimensional specification parameter symbol min typ max unit note strip length l 3002 mm active length = 300 strip width w 100.2 mm active width = 10mm strip thickness t 1.30. 15 mm 1mm rubber bonded magnet on 0.3mm stainless steel strip thermal expansion 17 x10 -6 /k mechanical length expansion density 3.5 1.43 3.65 4.64 3.8 7.85 g/cm 3 magnetic rubber stainless steel delivery single cut pieces without adhesive, rolls of 25m, 50m (up to 100m max.) 3 magnet specification parameter symbol min typ max unit note pole length l p 1.20 mm results in pole pair length of 2,40mm (250 poles @ 1.2mm) pole length deviation 1 1.5 % of 2*l p measured at bz=0, all poles within active area amplitude variation 10 % of b pk all poles within active area number of poles 250 poles excluding poles with l as53xx linear multipole magnetic strip magnet specification www.austrimaicrosystems.com revision 0.1 2 - 6 parameter symbol min typ max unit note cumulative error 40 20 10 m/m depending on accuracy grade standard a20 a10 thermal expansion 1e-4 1/k mechanical length expansion temperature range tamb -40 25 100 c scale mounted, no bending magnetization the ms12-250 magnet strip is magnetized on the top side and bonded on a steel support with elastomer a dhesive (bottom). note that the polarization of the magnet will change when it is rotated as the pole arrangem ent not symmetric. this will influence the position of the index pulse. an index pulse is generated when the north and sout h poles are placed over the hall array as shown in figure 2. the incremental output count increases when the mag net is moving to the left, facing the chip with pin #1 at the lower left corner (see figure 2 , top drawing). at the same time, the absolute posi tion information increases. likewise, the position information decreases when t he magnet is moved in the opposite direction. note that there is no hysteresis at the absolute output. in order to g et a stable 12-bit absolute reading, it may be nece ssary to filter the values by averaging, e.g. a moving average calc ulation in the external microcontroller. averaging 4 readings results in 6db (=50%) noise and jitter reduction. a n average of 16 readings reduces the jitter by a fa ctor of 4. mounting the magnet strip the magnet strip may be mounted directly on magneti c or non-magnetic surfaces. when magnetic surfaces are used, the strip must be mounted on top of the surfa ce, but not immersed in a cavity, as this may weake n the magnetic field of the magnet. when mounting the mag net on a non-magnetic surface, either method is acc eptable. for more rigid demands, magnet suppliers offer cust omized solutions where the magnet material is direc tly overmolded on the carrier, e.g. a shaft, bushing, p late, etc.. please contact your magnet supplier for more inform ation. a list of recommended suppliers is available for download on the austriamicrosystems website.
www.austrimaicrosystems.com revision 0.1 3 - 6 4 magnet dimensions figure 1 : ms12-250 strip dimensions l = 300 l =2.4 s bpk bpk 1 2 3 4 5 6 249 250 10 w = 10 t = 1.2 8 7 recommended scanning path 247 248 n n s n s n s n s n s alignment of magnet strip and sensor ic when aligning the magnet strip to the as5306 sensor ic, the centerline of the magnet strip should be p laced exactly over the hall array. see figure 2 for the position of the hall array relative to pin #1. vertical distance the vertical distance between the magnet strip and the top of the ic package should be 0.4mm . note that the vertical distance depends on the strength of the ma gnet. the as5306 automatically adjusts for fluctuat ing magnet strength by using an automatic gain control (agc). there are several indicators for proper magnetic fi eld strength available with the as5306. the vertical distance sh ould be set such that the ao voltage is between 1.0 and 4.0v . see the as5306 datasheet for more details. see also error! reference source not found. for measurement data of the ms12-250 magnetic stri p. lateral stroke the lateral movement range (stroke) can cover the active area of the magnetic strip (see figure 1) as long as all hall sensors of the ic are covered by the magnet. t he hall array on the as5306 has a length of 2.0mm, hence the total stroke is stroke = length of active area C length of hal arra y = 300.0mm C 2.0mm = 298.0mm
as53xx linear multipole magnetic strip magnet specification www.austrimaicrosystems.com revision 0.1 4 - 6 figure 2 : alignment of magnet strip with as5306 sensor ic 1.00 0.1 3.04750.235 3.2000.235 die c/l 2.5760.235 note: all dimensions are in mm s n s n s n s n s n as5306 package outline 3.04750.235 die c/l s n s n s n s n s n see text leftmost magnet position vertical airgap 1.00 1.00 magnet strip carrier rightmost magnet position position value increases position value decreases note that the polarization of the magnet will be re versed when it is rotated or flipped (see magnetiza tion for more details).
as53xx linear multipole magnetic strip magnet specification www.austrimaicrosystems.com revision 0.1 5 - 6 5 adhesive tape specification
www.austrimaicrosystems.com revision 0.1 6 - 6 copyrights copyright ? 2011, austriamicrosystems ag, schloss p remstaetten, 8141 unterpremstaetten, austria-europe . trademarks registered ?. all rights reserved. the m aterial herein may not be reproduced, adapted, merg ed, translated, stored, or used without the prior writt en consent of the copyright owner. all products and companies mentioned are trademarks or registered trademarks of their respective compa nies. disclaimer devices sold by austriamicrosystems ag are covered by the warranty and patent indemnification provisio ns appearing in its term of sale. austriamicrosystems ag makes no warranty, express, statutory, implied, or by description regarding the information set forth her ein or regarding the freedom of the described devic es from patent infringement. austriamicrosystems ag reserves the r ight to change specifications and prices at any tim e and without notice. therefore, prior to designing this product into a system, it is necessary to check wit h austriamicrosystems ag for current information. thi s product is intended for use in normal commercial applications. applications requiring extended tempe rature range, unusual environmental requirements, o r high reliability applications, such as military, medical life-support or lifesustaining equipment are speci fically not recommended without additional processing by austri amicrosystems ag for each application. the information furnished here by austriamicrosyste ms ag is believed to be correct and accurate. howev er, austriamicrosystems ag shall not be liable to recip ient or any third party for any damages, including but not limited to personal injury, property damage, loss of profit s, loss of use, interruption of business or indirec t, special, incidental or consequential damages, of any kind, i n connection with or arising out of the furnishing, performance or use of the technical data herein. no obligation or liability to recipient or any third party shall ari se or flow out of austriamicrosystems ag rendering of technical or ot her services. contact information headquarters austriamicrosystems ag a-8141 schloss premstaetten, austria tel: +43 (0) 3136 500 0 fax: +43 (0) 3136 525 01 magnet supplier information bogen electronic gmbh1, potsdamer strasse 12-13 14163 berlin germany http://www.bogen-electronic.de/ for sales offices, distributors and representatives, please visit: http://www.austriamicrosystems.com/contact
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