agilent aedr-8300 series encoders reflective surface mount optical encoder data sheet description the aedr-8300 series is the smallest optical encoder employ- ing reflective technology for motion control purposes. the encoder houses an led light source and a photo-detecting circuitry in a single package. the aeds-8300 series offers options of either single channel or two-channel quadrature digital outputs. being ttl compatible, the outputs of the aedr-8300 series can be interfaced directly with most of the signal process- ing circuitries. hence the encoder provides great design-in flexibil- ity and easy integration into existing systems. the aedr-8300 series is available in four resolu- features reflective technology surface mount small outline leadless package single channel incremental output two channel quadrature outputs for direction sensing ttl compatible output single 5v supply -20 o c to 85 o c absolute operating temperature encoding resolution options: 36, 75, 150, 180 (lines/inch) or 1.42, 2.95, 5.91, 7.09 (lines/inch) tions, namely 36, 75, 150 and 180 lines per inch (lpi) (1.42, 2.95, 5.91 and 7.09 lines per mm respec- tively). this range of resolutions caters for different design and application needs. applications the aedr-8300 series provides motion sensing at a competitive cost, making it ideal for high volume applications. its small size and surface mount package make it ideal for printers, copi- ers, card readers and many consumer products, particularly where space and weigh are design constraint. note: all specifications are subject to change without prior notification.
2 theory of operation the aedr-8300 series combines an emitter and a detector in a single surface mount leadless package. when used with a codewheel or linear codestrip, the encoder translates rotary or linear motion into digital outputs. as seen in the block diagram, the aedr-8300 consists of three major components: a light emit- ting diode (led) light source, a detector ic consisting photo- diodes 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 motion of an object being monitored is converted to equivalent light pattern via the use of codewheel/codestrip. as shown in the above diagram, the reflective area (window) of the codewheel (or codestrip) reflects light back to the photodetector ic, whereas no light is reflected by the non-reflective area (bar). an alternating light and dark patterns corresponding to the window and bar fall on the photodiodes as the codewheel rotates. the moving 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 is then a direct representation of the motor rotation. the same con- cept applies to the use of a codestrip to detect linear motion. definitions state width (s) : the number of electrical degrees between a transition in channel a and the neighboring transition in chan- nel b. there are 4 states per cycle, each nominally 90 o e. state width error ( ? s) : the deviation of state width, in electrical degree, from its ideal value of 90 o e. phase ( ) : the number of electri- cal degrees between the center of high state of channel a and the center of high state of channel b. nominally 90 o e. phase error ( ? ) : the deviation of phase, in electrical degree, from its ideal value of 90 o e. pulse width (p) : the duration of high state of the output, in electrical degree, within one cycle. nominally 180 o e or half a cycle. pulse width error ( ? p) : the deviation of pulse width, in electrical degree, from its ideal value of 180 o e. count (n) : the number of window and bar pair per revolu- tion (cpr) of codewheel. for linear codestrip, defined as the number of window and bar pair per unit length (lines per inch [lpi] or lines per mm [lpmm]). one cycle (c) : 360 electrical degrees ( o e). equivalent to one window and bar pair. one shaft rotation : 360 me- chanical degrees. also equivalent to n counts (codewheel only). line density : the number of window and bar pair per unit length, expressed in either lines per inch (lpi) or lines per mm (lpmm). optical radius (rop) : the distance between the codewheel center and the centerline be- tween the two domes of the encoder. figure 1. block diagram of aedr-8300. v led gnd v cc ch a ch b gnd signal processing circuitry r codewhee l or codestrip
3 gap (g) : the distance from surface of the encoder to the surface of codewheel or codestrip. specular reflectance (r f ) : the amount of incident light reflected by a surface. quantified in terms of the percentage of incident light. a spectrometer can be used to measure specular reflectance of a surface (contact factory for more information). aedr-8300 shaft codewheel radial (e r ) tangential (e t ) aedr-8300 shaft codewheel angular (e a ) s1 s2 s3 s4 p c ch. b ch. a all four states (s1 to s4) are maintained. codewheel rotation or linear movement amplitude radial and tangential mis- alignment error (e r , e t ) : for rotary motion, mechanical dis- placement 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.
4 aedr-8300 absolute maximum ratings storage temperature, t s -40 c to 85 c operating temperature, t a -20 c to 85 c 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 flashbulbs 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 degradation induced by esd. 3. proper operation of the encoder cannot be guaranteed if the maximum ratings are exceeded. aedr-8300 recommended operating conditions parameter sym. min. typ. max. units notes temperature t a 02585 c supply voltage v cc 4.5 5 5.5 v ripple< 100mvp-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 aedr-83x0-k/p/q see note 2 count frequency f 15 khz aedr-8310-v radial misalignment e r 0.38 ( 0.015) mm (in.) tangential misalignment e t 0.38 ( 0.015) mm (in.) 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 ?ed current limiting resistor?in page 6. 2. count frequency = velocity(rpm)xn/60.
5 aedr-8300 encoding characteristics encoding characteristics over the recommended operating condition and mounting conditions. parameter symbol typical maximum units notes pulse width error ? p15 55 e aedr-8310-k 16 75 e aedr-8310-v pulse width error (ch.a, ch. b) ? p 15, 25 55, 75 e aedr-8300-k ? p16 75 e aedr-8300-p ? p1 75 e aedr-8300-q phase error ? 12 60 e aedr-8300-k ? 10 60 e aedr-8300-p ? 10 60 e aedr-8300-q note: 1. typical values represent the encoder performance at typical mounting alignment, whereas the maximum values represent the enco der performance across the range of recommended mounting tolerance. aedr-8300 electrical characteristics characteristics over recommended operating conditions at 25 c. parameter sym. min. typ. max. units 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, r l = 2.7 k ? fall time t f 100 ns c l = 25 pf, r l = 2.7 k ? aedr-8300 encoder pin configuration encoder option pin 1 pin 2 pin 3 pin 4 pin 5 pin 6 aedr-8310-k/v nc gnd v led gnd ch a v cc aedr-8300-k/p/q ch b gnd v led gnd ch a v cc
6 r op w b w w l w l w w w w b recommended codewheel and codestrip characteristics led current limiting resistor a resistor to limit current to the led is required. the recom- mended value is 220 ? ( 10 %) and the resistor should be placed in series between the 5v supply and pin 3 of the device (v led ). this will result in an led cur- rent of approximately 15 ma. moisture sensitive level the aedr-8300 series is speci- fied to moisture sensitive level (msl) 3. 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) spectular reflectance r f 60 85 reflective area. see note 1. 10 non-reflective area line density lpmm (lpi) 1.42 (36) 1.42 (36) lines/mm (inch) aedr-8310-v lpmm (lpi) 2.95 (75) 2.95 (75) lines/mm (inch) aedr-8310-k, aedr-8300-k lpmm (lpi) 5.91 (150) 5.91 (150) lines/mm (inch) aedr-8300-p lpmm (lpi) 7.09 (180) 7.09 (180) lines/mm (inch) aedr-8300-q optical radius rop 11 11 mm recommended value notes: 1. measurements from spectrometer. contact factory for more information. 2. contact factory for more information on compatibility of codewheel/strip.
7 0.95 0.60 2.06 1.96 pin 4 pin 5 pin 6 pin 1 pin 2 pin 3 3.96 5.12 pin 3 pin 4 pin 5 pin 6 pin 2 pin 1 all dimensions in millimeters. tolerance x.xx 0.15 mm. 1.63 5.12 3.96 1.63 chamfer detector emitter + outline drawing note: for ease of reference, a chamfer is marked on the detector side (pin 6), as shown in the above diagram. encoder orientation the aedr-8300 series is de- signed such that both the led and detector ic should be placed parallel to the window/bar orientation, as shown. as such, the encoder is tolerant against radial play of 0.38 mm. the emitter side (pins 3 and 4) should be placed closer to the rotating shaft. codewheel direction of radial play direction of radial play codestrip
8 mounting consideration direction of codewheel rotation with the emitter side (pins 3 and 4) of the encoder placed closer to the codewheel centre, channel a leads channel b when the codewheel rotates anti-clockwise and vice versa. rop gap codewheel/codestrip 11.00 mm (0.433 in) < rop < ch. a leads ch. b emitter ch. b leads ch. a emitter anti- clockwise clockwise viewed from top
9 mounting center 0.72 1.96 1.08 0.94 note: the shaded areas are the leads for soldering. note: the shaded areas are not encoder pin-outs. they are electrically grounded and physically exposed. pcb layout with tracks running across these areas should be avoided. recommended land pattern for aedr-8300 series recommended lead-free reflow soldering temperature profile 0 50 100 150 200 250 300 time (sec.) 60 - 1 50 sec 125 c temperature ( c) cool down heat up solder paste dry solder reflow 120 sec max 40 c 10 - 20 sec 255 c 250 c 217 c preheat temperature 40 c to 125 c = 120 sec max temperature maintain above 217 c = 60-150 sec peak temperature = 255 5 c time above 250 c = 10-20 sec note: due to treatment of high temperature, aedr-8300 trans- parent compound is expected to turn yellow after ir reflow.
www.agilent.com/semiconductors for product information and a complete list of distributors, please go to our web site. for technical assistance call: americas/canada: +1 (800) 235-0312 or (916) 788-6763 europe: +49 (0) 6441 92460 china: 10800 650 0017 hong kong: (65) 6756 2394 india, australia, new zealand: (65) 6755 1939 japan: (+81 3) 3335-8152(domestic/international), or 0120-61-1280(domestic only) korea: (65) 6755 1989 singapore, malaysia, vietnam, thailand, philippines, indonesia: (65) 6755 2044 taiwan: (65) 6755 1843 data subject to change. copyright ? 2004 agilent technologies, inc. january 30, 2004 5989-0464en ordering information aedr-83 0 option number of channel 1 C one channel 0 C two channels packaging 1 C tape and reel lines per inch k C 75lpi p C 150lpi q - 180lpi v - 36lpi shipping units 0 C 1000 pcs 1 C 500 pcs 2 - 100 pcs resolution indicator since the encoder is too small to imprint resolution marking on its package, color-coding the package is employed to differentiate resolu- tions. the details are: 36 lpi = green package 75lpi = clear package 150lpi = red package 180lpi = amber package note: encoders are packed in tape in quantities of 100, 500 or 1000 pieces.
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