features and benefits sensor products linear / angular / rotary displacement sensors HMC1501 / hmc1512 applications igh resolution, low power mr sensor capable of measuring the angle direction of a magnetic field from a magnet with <0.07 resolution. advantages of measuring field direction versus field strength include: insensitivity to the tempco of the magnet, less sensitivity to shock and vibration, and the ability to withstand large variations in the gap between the sensor and magnet. these sensors may be operated on 3 volts with bandwidth response of 0-5 mhz. output is typical wheatstone bridge. no rare earth magnets unlike hall effect devices which may require samarium cobalt or similar rare earth magnets, the HMC1501 and hmc1512 can function with alnico or ceramic type magnets. wide angular range HMC1501angular range of 45 with <0.07 resolution. hmc1512angular range of 90 with <0.05 resolution. effective linear range linear range of 8mm with two sensors mounted on two ends; range may be increased through multiple sensor arrays operating together. absolute sensing unlike incremental encoding devices, sensors know the exact position and require no indexing for proper positional output. non-contact sensing no moving parts to wear out; no dropped signals from worn tracks as in conventional contact based rotary sensors. small package available in an 8-pin surface mount package with case dimensions (exclusive of pins), of 5mm x 4mm x 1.2mm total mounting envelope, with pins of less than 6mm square. large signal output full scale output range of 120mv with 5v of power supply. linear displacement angular displacement motor control valve position proximity detection current spike detection not actual size h
2 HMC1501 / hmc1512 sensor products anisotropic magnetoresistance (amr) occurs in ferrous materials. it is a change in resistance when a magnetic field is applied in a thin strip of ferrous material. the mag- netoresistance is a function of cos 2 where is the angle between magnetization m and current flow in the thin strip. when an applied magnetic field is larger than 80 oe, the magnetization aligns in the same direction of the applied field; this is called saturation mode. in this mode, is the angle between the direction of applied field and the current flow; the mr sensor is only sensitive to the direction of applied field. the sensor is in the form of a wheatstone bridge (figure 1). the resistance r of all four resistors is the same. the bridge power supply v s causes current to flow through the resistors, the direction as indicated in the figure for each resistor. both HMC1501 and hmc1512 are designed to be used in saturation mode. HMC1501 contains one mr bridge and hmc1512 has two identical mr bridges, coexisting on a single die. bridge b physically rotates 45 from bridge a. the HMC1501 has sensor output ? v=-v s s sin (2 ) and the hmc1512 has sensor output ? v=v s s sin (2 ) for sen- sor a and sensor b output ? v s =-v s s cos (2 ), where v s is supply voltage, s is a constant, determined by materials. for honeywell sensors, s is typically 12mv/v. principles of operation mr sensor circuits figure 1 current flow permalloy thin film (nife) metal contact aaaaaaa aa m applied field pinout drawings out+ 1 gnd 1 2 3 4 ? 8 out- 7 gnd 2 6 5 vbridge ? 8 7 6 5 1 2 3 4 out- a out- b vbridgeb vbridgea gnda gndb out+ b out+ a HMC1501 hmc1512 caution: do not connect gnd or power to pin 3,4 &6. out+ a out- a vbridge a gnd a b r id ge a r r r r out+ out- vbridge gnd 1 r r r r gnd 2 vbridge b out +b out -b gnd b b r id ge b r r r r + - ? v r + ? r m m r- ? r r+ ? r r- ? r mm applied field direction vs i
3 typical sensor output HMC1501 / hmc1512 sensor products rotating shaft rotating shaft n s s n magnet ns magnet HMC1501/1512 mr sensor application configuration n ~0.5 to -1.5 inches valve actuator stem proximity position rotary position linear position HMC1501 output voltage vs. magnetic field angle hmc1512 output voltage vs. magnetic field angle -100 -80 -60 -40 -20 0 20 40 60 0 100 200 300 400 theta (degree) sensor output (mv) -100 -50 0 50 100 0 100 200 300 400 theta (degree) sensor output (mv) bridge a bridge b b a reference direction n s moving direction moving direction package drawing 8-pin soic d e b 1 h x 45 e a ? h a1 symbol a a1 b d e e h h min 1.371 0.101 0.355 4.800 3.810 1.270 ref 5.816 0.381 max 1.728 0.249 0.483 4.979 3.988 6.198 0.762 min .054 .004 .014 .189 .150 .050 ref .229 .015 max .068 .010 .019 .196 .157 .244 .030 millimeters inches
4 honeywell reserves the right to make changes to any products or technology herein to improve reliability, function or design. h oneywell does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others. specifications HMC1501 / hmc1512 sensor products solid state electronics center 12001 state highway 55 plymouth, mn 55441 1-800-323-8295 http://www.ssec.honeywell.com 900246 8-00 rev. b 1 ka/m = 12.5 gauss 1 tesla = 10 4 gauss offset tempco c o = v o (t) - v o ( o ) = -0.01%/ c v p-p *t where v o ( o ) = bridge offset at zero temperature v p-p = peak-to-peak voltage t = temperature in the range -40 c to 125 c v o (t) = offset at temperature t power consumption p = where v = bridge supply voltage r = bridge resistance v 2 r *tested at 25 c except stated otherwise. sensitivity tempco c s =s t -s o = -0.32%/ c s o *t where s o = sensitivity at zero temperature t = temperature in the range -40 c to 125 c s t = sensitivity at temperature t s c i t s i r e t c a r a h c* s n o i t i d n o c1 0 5 1 c m h x a m p y t n i m 2 1 5 1 c m h x a m p y t n i m s t i n u y l p p u s e g d i r bd n g o t d e c n e r e f e r e g d i r b v155 2155 2v e c n a t s i s e r e g d i r ba m 1 t n e r r u c e g d i r b455 . 60 . 21 . 28 . 2k ? e g n a r e l g n a> d l e i f n o i t a r u t a s5 4 -5 4 +0 9 -0 9 +g e d y t i v i t i s n e s , e o 0 8 d l e i f , v 5 = e g d i r b v g n i s s o r c o r e z @ ) 1 ( d e g a r e v a , g n i s s o r c o r e z @ ) 2 ( 5 4 f o e g n a r e h t n i 1 . 2 8 . 1 1 . 2 8 . 1 / v m e g a t l o v k a e p - o t - k a e pe o 0 8 = d l e i f , v 5 = e g d i r b v0 0 10 2 10 4 10 0 10 2 10 4 1v m t e s f f o e g d i r b , e o 0 8 d l e i f a e g d i r b 0 = b e g d i r b 7 -37 0 4 - 5 . 2 0 5 1 v / v m d l e i f n o i t a r u t a ss f % 3 0 . 0 < y t i l i b a t a e p e r0 80 8g h t d i w d n a bl a n g i s c i t e n g a m0505z h m n o i t u l o s e rv 5 = e g d i r b v , z h 0 1 = h t d i w d n a b7 0 . 05 0 . 0 r o r r e s i s e r e t s y h d l e i f c i t e n g a m> , d l e i f n o i t a r u t a s v 5 = e g d i r b v 0 3 0 1 x 7 . 1 2 - 0 3 0 1 x 7 . 1 2 - v g e d e g d i r b ? o c p m e tt a c 5 2 1 + o t c 0 4 - =8 2 . 08 2 . 0c / % o c p m e t y t i v i t i s n e s t a c 5 2 1 + o t c 0 4 - = v 5 = e g d i r b v 2 3 . 0 -2 3 . 0 -c / % o c p m e t t e s f f o e g d i r bt a c 5 2 1 + o t c 0 4 - =1 0 . 0 -1 0 . 0 -s f , c / % y t i s n e d e s i o nv 5 = e g d i r b v , z h 1 t a e s i o n0 0 10 7z h v n n o i t p m u s n o c r e w o pv 5 = e g d i r b v53 2w m
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