features ? refective technology ? surface mount small outline leadless package ? direct replacement of hedr-8000 encoder ? single channel incremental output ? two channels quadrature outputs for direction sensing ? single 5 v supply, ttl compatible output ? -20c to 85c absolute operating temperature ? lead-free package ? encoding resolution options: 75, 150 and 180 (lines/inch) or 2.95, 5.91, 7.09 (lines/mm) ? pcb height profle options: 1.0 mm pcb thickness 1.5 mm pcb thickness description by introducing an additional pcb top-up thickness at - tached to the encoder, the aedr-8000 encoder series could easily solve the height issue in various applica - tions. furthermore, this great feature is enhanced with the ofering of diferent height profle options. direct replacement of hedr-8000 encoder series is now possible with the aedr-8000 encoder series. such migra - tion is always simple and easy due to the perfect match - ing of the height profles as well as same footprints in both encoder series. the aedr-8000 encoder series employs refective tech - nology for rotary and linear movement control. the en - coder houses an led light source and a photo-detecting circuitry in a single package. in adding on to the main features, the aedr-8000 en - coder series ofers two-channel quadrature digital out - puts (ttl compatible) where signal could be interfaced directly with most of the signal processing circuitries. thus, its bound to reduce the design time of an applica - tion. applications the aedr-8000 encoder series provides motion sensing at a competitive price, making it ideal for high volume applications. its small size and surface mount package make it ideal for printers, copiers, card readers and many consumer products, particularly where space and weight are design constraints. note: all specifcations are subject to change without prior notifcation. aedr-8000 series refective surface mount optical encoder data sheet
2 block diagram of aedr-8000 encoder phase error ( df ): the deviation of phase, in electrical de - grees, from its ideal value of 90e. pulse width (p): the duration of high state of the output, in electrical degrees, within one cycle. nominally 180e or half a cycle. pulse width error ( d p): the deviation of pulse width, in electrical degrees, from its ideal value of 180e. count (n): the number of window and bar pairs per revo - lution (cpr) of codewheel. for linear codestrip, defned as the number of window and bar pairs per unit length (lines per inch [lpi] or lines per mm [lpmm]). one cycle (c): 360 electrical degrees (e). equivalent to one window and bar pair. one shaft rotation: 360 mechanical degrees. also equiv - alent to n counts (codewheel only). line density: the number of window and bar pairs per unit length, expressed in either lines per inch (lpi) or lines per mm (lpmm). optical radius (rop): the distance between the code - wheel center and the centerline between the two domes of the encoder. gap (g): the distance from the surface of the encoder to the surface of codewheel or codestrip. specular refectance (r f ): the amount of incident light refected by a surface. quantifed in terms of the per - centage of incident light. a spectrometer can be used to measure specular refectance of a surface (contact fac - tory for more information). radial and tangential misalignment error (e r , e t ): for ro - tary motion, mechanical displacement in the radial and tangential directions relative to the nominal alignment. angular misalignment error (e a ): angular displacement of the encoder relative to the tangential line. theory of operation the aedr 8000 encoder series combines an emitter and a detector in a single surface mount leadless package. when used with a codewheel or linear codestrip, the en - coder translates rotary or linear motion into digital out - puts. as seen in the block diagram, the aedr-8000 en - coder series consists of three major components: a light emitting diode (led) light source, a detector ic consist - ing photodiodes, and lens to focus light beam from the emitter as well as light falling on the detector. the operation of the encoder is based on the principle of optics where the detector photodiodes sense the absence and presence of light. in this case, the rotary/linear mo - tion of an object being monitored is converted to equiv - alent light pattern via the use of codewheel/codestrip. as shown in the above diagram, the refective area (win - dow) of the codewheel (or codestrip) refects light back to the photodetector ic, whereas no light is refected by the non-refective area (bar). an alternating light and dark pattern, corresponding to the window and bar, falls on the photodiodes as the codewheel rotates. the mov - ing light pattern is exploited by the detector circuitry to produce digital outputs representing the rotation of the codewheel. when the codewheel is coupled to a motor, the encoder outputs are then a direct representation of the motor rotation. the same concept applies to the use of a codestrip to detect linear motion. defnitions state width (s): the number of electrical degrees be - tween a transition in channel a and the neighboring transition in channel b. there are 4 states per cycle, each nominally 90e. state width error ( d s): the deviation of state width, in electrical degrees, from its ideal value of 90e. phase ( f ): the number of electrical degrees between the center of high state of channel a and the center of high state of channel b. nominally 90e. signal processing circuitry v cc ch a v led gnd ch b gnd r codewheel or codestrip
3 output waveform ch. a all four s ta tes (s1 to s4) are maint ained. ch. b s1 p c s2 s3 codewheel ro ta tion or linear movement amplitude s4 shaft radial (e r ) t angential (e t ) aedr -8000 codewheel shaft angular (e a ) aedr -8000 codewheel absolute maximum ratings storage temperature, t s -40c to 85c operating temperature, t a -20c to 85c supply voltage, v cc -0.5 v to 7 v output voltage, v o -0.5 v to v cc output current per channel, i out -1.0 ma to 8 ma esd human body model jesd22-a114-a class 2 machine model jesd22-a115-a class b notes: 1. exposure to extreme light intensity (such as from fashbulbs or spotlights) may cause permanent damage to the device. 2. caution: it is advised that normal static precautions should be taken when handling the encoder in order to avoid damage and/or degrada - tion induced by esd. 3. proper operation of the encoder cannot be guaranteed if the maximum ratings are exceeded.
4 recommended operating conditions parameter sym. min. typ. max. units notes temperature t a 0 25 85 c supply voltage v cc 4.5 5.0 5.5 v ripple < 100 mvp-p led current i led 13 15 18 ma see note 1 load capacitance c l 100 pf 2.7 k pull-up count frequency f 30 khz see note 2 radial misalignment e r 0.38 mm (in.) (0.015) tangential misalignment e t 0.38 mm (in.) ( 0.015) angular misalignment e a 0 1.5 deg. codewheel/strip tilt c t 0 1 deg. codewheel/strip gap g 1.0 (0.04) 2.0 (0.08) 2.5 (0.10) mm (in.) note: 1. refer to led current limiting resistor on page 5. 2. count frequency = velocity (rpm) x n/60. encoding characteristics encoding characteristics over the recommended operating condition and mounting conditions. parameter symbol typical maximum unit notes pulse width error d p 15 55 e aedr-8010-k pulse width error (ch. a, ch. b) d p 15, 25 55, 75 e aedr-8000-k 16 75 aedr-8100-p 16 75 aedr-8100-q phase error df 12 60 e aedr-8000-k 10 60 aedr-8100-p 10 60 aedr-8100-q note: typical values represent the encoder performance at typical mounting alignment, whereas the maximum values represent the encoder performance across the range of recommended mounting tolerance. electrical characteristics characteristics over recommended operating conditions at 25c. parameter symbol min. typ. max. unit notes detector supply current i cc 2.2 5.0 ma high level output voltage v oh 2.4 v i oh = -0.2 ma low level output voltage v ol 0.4 v i ol = 8.0 ma rise time t r 500 ns c l = 25 pf fall time t f 100 ns r l = 2.7 k
5 recommended codewheel and codestrip characteristics parameter symbol min. max. unit notes window/bar ratio ww/wb 0.9 1.1 window/bar length l w 1.80 (0.071) 2.31 (0.091) mm (inches) specular refectance r f 60 85 refective area. see note 1. C 10 nonrefective area 2.95 (75) aedr-80x0-k 5.91 (150) aedr-8100-p 7.09 (180) aedr-8100-q optical radius rop 11 C mm recommended value notes: 1. measurements from tma scan meter. contact factory for more information. 2. contact factory for more information on compatibility of codewheel/strip. led current limiting resistor a resistor to limit current to the led is required. the recommended value is 220 (10 %) and the resistor should be placed in series between the 5 v supply and pin 3 of the device (v led ). this will result in an led current of approximately 15 ma. moisture sensitive level the aedr-8000 series is specifed to moisture sensitive level (msl) 3. w b w w w w w b l w r op l w
6 package outline drawing 2.7 1.5 side view (low resolution) side view (high resolution) 1.65 0.38 0.59 1.30 0.78 4.38 6.23 1.02 0.7 0.4 1.04
7 encoder orientation the aedr-8000 series is designed such that both the led and detector ic should be placed parallel to the window/ bar orientation, as shown. as such, the encoder is toler - ant against radial play of 0.38 mm. the emitter side should be placed closer to the rotating shaft. mounting consideration direction of codewheel rotation with the emitter side of the encoder placed closer to the codewheel centre, channel a leads channel b when the codewheel rotates anti-clockwise and vice versa. viewed from top codestrip direction of radial pla y codewheel direction of radial pla y ch. a leads ch. b emitter anti-clockwise ch. b leads ch. a emitter clockwise r op 11.00 mm (0.433 in) < r op < codewheel/codestrip gap
8 recommended lead-free refow soldering temperature profle preheat temperature 40c to 125c = 120 sec. max. temperature maintain above 217c = 60 C 150 sec. peak temperature = 255 5c time above 250c = 10 C 20 sec. note: due to treatment of high temperature, aedr-8000 transparent compound is expected to turn yellow after ir refow. resolution indicator since the encoder is too small to imprint resolution marking on its package, color-coding the package is em - ployed to diferentiate resolutions. the details are: lpi 75 150 180 color clear red amber 300 250 200 150 100 50 0 1 22 45 66 87 108 129 150 171 192 213 235 256 278 299 320 341 363 384 255 c 250 c 217 c 40 c 125 c 10 - 20 sec. 120 sec. max. 60 - 150 sec. time (sec.) hea t up solder p aste dry solder reflow cool down tempera ture (c)
ordering information aedr-8 0 option pcb thickness number of packaging lines per inch shipping units 0 - 1.5 mm (low channels 1 - tape and k - 75 lpi 0 - 1000 pcs resolution) 1 - one channel reel p - 150 lpi 1 - 500 pcs 1 - 1.0 mm (high 0 - two channels q - 180 lpi 2 - 100 pcs resolution) note: encoders are packed in tape of quantity 1000 pcs or 500 pcs or 100 pcs. available options resolution shipping units k C p C q C 0 C 1 C 2 C encoder 75 lpi 150 lpi 180 lpi 1000 pcs 500 pcs 100 pcs aedr-8000 * * * * aedr-8010 * * aedr-8100 * * * * aedr-8100 * * * for product information and a complete list of distributors, please go to our website: www.avagotech.com avago, avago technologies, and the a logo are trademarks of avago technologies in the united states and other countries. data subject to change. copyright ? 2005-2009 avago technologies. all rights reserved. obsoletes 5989-3067en av02-0971en - august 27, 2009
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