AEDR-8300-1W2

AEDR-8300-1Wx Encoders Reflective Surface Mount Optical Encoder Data Sheet Description Features The AEDR-8300-1Wx is the smallest optical encoder employing reflective technology for motion control purposes. The encoder houses an LED light source and a photo-detecting circuitry in a single package. • Reflective technology The AEDR-8300-1Wx offers two-channel quadrature digital outputs. Being TTL compatible, the outputs of the AEDR-8300-1Wx can be interfaced directly with most of the signal processing circuitries. Hence the encoder provides great design-in flexibility and easy integration into existing systems. The AEDR-8300-1Wx could yields encoding resolution at 212 lines per inch (LPI) which is 8.35 lines per mm. The AEDR-8300-1Wx 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 many consumer products, particularly where space and weigh are primary design constraint. • Surface mount leadless package • Two channel quadrature outputs for direction sensing • TTL compatible output • Single 3.3 V to 5 V supply • -20° C to 85° C absolute operating temperature • Encoding resolution: 212 (lines/inch) or 8.35 (lines/mm) Applications Ideal for high volume applications: • Printers • Copiers • Card readers • Scanners • Cameras • Motor Solutions • Automated Wheel-chair • Vending Machines • Low Servo Systems • ATM Machines • Textile Machines • Industrial Sewing Machines • Consumer Product Applications Theory of Operation Definitions The AEDR-8300-1Wx 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-8300-1Wx consists of three major components: a light emitting diode (LED) light source, a detector IC consisting photodiodes and lens to focus light beam from the emitter as well as light falling on the detector. State Width (S): The number of electrical degrees between Block Diagram of AEDR-8300-1Wx VLED R GND State Width Error (∆S): The deviation of state width, in electrical degree, from its ideal value of 90°e. Phase (φ): The number of electrical degrees between the center of high state of Channel A and the center of high state of Channel B. Nominally 90°e. Phase Error (∆φ): The deviation of phase, in electrical degree, from its ideal value of 90°e. CODEWHEEL or CODESTRIP VCC Pulse Width (P): The duration of high state of the output, in electrical degree, within one cycle. Nominally 180°e or half a cycle. Pulse Width Error (∆P): The deviation of pulse width, in elec- CH A CH B a transition in Channel A and the neighboring transition in Channel B. There are 4 states per cycle, each nominally 90°e. SIGNAL PROCESSING CIRCUITRY GND trical degree, from its ideal value of 180°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 (°e). Equivalent to one window and bar pair. 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 are then a direct representation of the motor rotation. The same concept applies to the use of a codestrip to detect linear motion. One Shaft Rotation: 360 mechanical 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 between the two domes of the encoder. Gap (G): The distance from surface of the encoder to the surface of codewheel or codestrip. Radial and Tangential Misalignment Error (ER, ET): For rotary motion, mechanical displacement in the radial and tangential directions relative to the nominal alignment. Angular Misalignment Error (EA): Angular displacement of the encoder relative to the tangential line. Specular Reflectance (Rf ): 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). 2 Output waveform C ALL FOUR STATES (S1 to S4) ARE MAINTAINED P AMPLITUDE CH. A S1 S2 S3 S4 φ CH. B CODEWHEEL ROTATION OR LINEAR MOVEMENT RADIAL (E R ) ANGULAR (EA ) TANGENTIAL (E T ) AEDR-8300-1Wx AEDR-8300-1Wx SHAFT SHAFT CODEWHEEL CODEWHEEL Absolute Maximum Ratings Storage Temperature, TS -40° C to 85° C Operating Temperature, TA -20° C to 85° C Supply Voltage, VCC -0.5 V to 7 V Output Voltage, VO -0.5 V to VCC Output Current per Channel, IOUT -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. 3 Recommended Operating Conditions Parameter Symbol Minimum Typical Maximum Units Temperature TA -20 25 85 °C Supply Voltage VCC 3.0 3.3 / 5.0 5.5 V Ripple < 100 mVp-p LED Current ILED 13 15 18 mA See Note 1 Load Capacitance CL 100 pF 2.7 kW Pull-Up Count Frequency2 F 60 kHz See Note 3 Radial Misalignment ER ±0.38 (±0.015) mm (in.) Tangential Misalignment ET ±0.38 (±0.015) mm (in.) Angular Misalignment EA 0 ±1.5 deg. Codewheel/strip tilt CT 0 1 deg. Codewheel/strip Gap G 2.0 (0.08) 2.5 (0.10) mm (in.) 0.3 1.0 (0.04) Notes Notes: 1. LED Current Limiting Resistor: For Vcc = 5.0 V, recommended series resistor = 220 Ω (±10 %) For Vcc = 3.3 V, recommended series resistor = 110 Ω (± 10 %) 2. Count frequency = velocity (rpm) x N / 60. 3. Data collected based on Avago production characterization. Encoding Characteristics Encoding characteristics over the recommended operating condition and mounting conditions. Parameter Symbol Typical Maximum Unit Pulse Width Error (Ch.A, Ch.B) DP 16 75 °e Phase Error Df 10 60 °e Note: 1. 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 25° C. Parameter Symbol Detector Supply Current ICC Minimum Typical Maximum Unit Notes 4.8 6.0 mA Vcc = 5 V 3.9 4.1 High Level Output Voltage VOH Low Level Output Voltage VOL Rise Time tr 500 Fall Time tf 100 ns 4 2.4 Vcc = 3.3 V 0.4 V IOH = -0.2 mA V IOL = 8.0 mA ns CL = 25 pF RL = 2.7 kW Recommended Codewheel and Codestrip Characteristics Wb Ww Lw Rop Lw W w Wb Parameter Symbol Minimum Maximum Window/bar Ratio Ww/Wb 0.9 1.1 Window/bar Length LW 1.80 (0.071) 2.31 (0.091) Specular Reflectance Rf 60 85 Reflective area. See note 1. – 10 Non reflective area 8.35 (212) Line Density LPmm (LPI) 8.35 (212) Optical radius Rop 11 Unit Notes mm (inches) lines/mm (lines/inch) mm Recommended value Notes: 1. Measurements from TMA µScan meter. Contact factory for more information. 2. Contact factory for more information on compatibility of codewheel/strip. LED Current Limiting Resistor Moisture Sensitive Level A resistor to limit current to the LED is required. The recommended value is 220 Ω (± 10%) and the resistor should be placed in series between the 5 V supply and pin 3 of the device (VLED). This will result in an LED current of approximately 15 mA. If 3.3 V voltage supply is used, the corresponded resistance would be 110 Ω (± 10%). The AEDR-8300-1Wx is specified to moisture sensitive level (MSL) 3. 5 Outline Drawing Chamfer PIN 1 PIN 6 Detector PIN 2 PIN 6 PIN 1 PIN 5 PIN 2 PIN 4 PIN 3 PIN 5 Emitter PIN 3 PIN 4 Top View Bottom View Side View Notes: 1. All dimensions in millimeter. 2. Tolerance X.XX ± 0.15mm. 3. For ease of reference, a chamfer is incorporated on the detector side (pin 6), as shown in the above diagram. Encoder Pin Configuration Encoder option Pin 1 Pin2 Pin3 Pin4 Pin5 Pin6 AEDR-8300-1Wx Ch B Gnd VLED Gnd Ch A Vcc Encoder Orientation The AEDR-8300-1Wx 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 tolerant against radial play of ± 0.38 mm. The emitter side (pins 3 and 4) should be placed closer to the rotating shaft. 6 Mounting Consideration Codewheel/codestrip Gap Rop 11.00 mm (0.433 IN) < Rop < ∝ 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. ANTI-CLOCKWISE CLOCKWISE EMITTER EMITTER CH. A LEADS CH. B LEADS CH. B CH. A Viewed from Top Recommended Land Pattern for AEDR-8300-1Wx 0.72 0.94 1.96 1.08 7 Mounting Center 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 Lead-free Reflow Soldering Temperature Profile 10 - 20 SEC. 300 255 C 250 C 250 TEMPERATURE (C) 217 C 200 120 SEC. MAX. 60 - 150 SEC. 150 125 C 100 50 0 40 C 1 22 45 66 87 108 129 150 171 192 213 235 256 278 299 320 341 363 384 TIME (SEC.) HEAT UP SOLDER PASTE DRY SOLDER REFLOW COOL DOWN 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-8300-1Wx compound may turn to yellow after IR reflow. Resolution Indicator Ordering Information Since the encoder is too small to imprint resolution marking on its package, color-coding the package is employed to differentiate resolutions. AEDR-8300 Option 1W Resolution (LPI) 212 Color Light Amber Shipping Units 0 – 1000 pcs 1 – 500 pcs 2 – 100 pcs Note: Encoders are packed in tape of quantity 1000 pcs, 500 pcs or 100 pcs. For product information and a complete list of distributors, please go to our web site: 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 © 2005-2013 Avago Technologies. All rights reserved. Obsoletes AV01-0178EN AV02-3572EN - September 9, 2013