Reflective Optical Surface Mount Encoders HEDR-8000 Series HEDR-8100 Series HEDR-8010 Series Technical Data Features Description • Reflective Technology • Surface Mount SO-8 Package • Two Channel Quadrature Outputs for Direction Sensing • Two Encoding Resolution Options: – 2.76 – 2.95 Lines/mm (70 – 75 Lines/inch) – 5.91 Lines/mm (150 Lines/inch) The HEDR-8000/8100 Series encoders use reflective technology to sense rotary or linear position. This sensor consists of an LED light source and a photodetector IC in a single SO-8 surface mount package. When used with a reflective codewheel or codestrip, this device can sense rotary or linear position. NOTE: HEDR-8000 series products are classified as MSL Level 3. Outline Drawing 8 7 6 5 1 NC 6.2 ± 0.20 (0.244 ± 0.008) 3.94 ± 0.13 * (0.155 ± 0.005) 1 2 3 1.270 TYP. (0.050) 0.38 ± 0.08 (0.016 ± 0.003) 5.08 ± 0.13 * (0.200 ± 0.005) 1.84 REF. (0.072) 3.18 ± 0.13 (0.125 ± 0.005) 0.700 R REF. (0.0276) NC 7 B 6 GND 5 2 GND 4 VCC 4 PIN ONE INDICATOR LOCATION 8 3 A 1.97 REF. (0.078) REF. VLED 1.40 ± 0.02 (0.055 ± 0.001) NOTES: *FLASH MAY ADD 0.38 (0.015) MAX. AT PARTING LINE. DIMENSIONS IN MILLIMETERS (INCHES). FOR THE 1CHANNEL HEDR-8010, PIN 6 IS CONSIDERED NC. 0.025 MIN. (0.001) 0.23 ± 0.03 (0.009 ± 0.001) 1.52 REF. (0.06) LEAD COPLANARITY ± 0.051 (0.002) 0.18 ± 0.08 (0.007 ± 0.003) 0.59 MIN. (0.023) ESD WARNING: NORMAL HANDLING PRECAUTIONS SHOULD BE TAKEN TO AVOID STATIC DISCHARGE. 2 The reflective surface mount optical encoders provide two square wave outputs in quadrature for count and direction information. These TTL compatible outputs correspond to the alternating reflective/nonreflective pattern of the codewheel or codestrip. The HEDR-8000/8100 series encoders can be used over a range of codewheel and codestrip resolutions. The HEDR-8000/ 8100 reflective encoder can operate from 2.76 to 2.95 lines per mm (70 to 75 lines per inch). The HEDR-8100 can be used with a codewheel or codestrip with 150 lines per inch (5.91 lines per mm). Applications The HEDR-8000/8100 series provides two channel motion sensing at a very low cost, making it ideal for high volume applications. Its small size and surface mount capability make it ideal for printers, copiers, card readers, and consumer product applications. Note: Agilent Technologies encoders are not recommended for use in safety critical applications. Eg. ABS braking systems, power steering, life support systems and critical care medical equipment. Please contact sales representative if more clarification is needed. Theory of Operation The HEDR-8000/8100 series combines an emitter and a detector in a single surface mount SO-8 package. When used with a codewheel or codestrip, the reflective sensors translates rotary or linear motion into a two channel digital output. Block Diagram VLED R GND VCC CH A CH B GND SIGNAL PROCESSING CIRCUITRY CODEWHEEL OR CODESTRIP As seen in the block diagram, the HEDR-8000/8100 series has three key parts: a single light emitting diode (LED) light source, a photodetector IC with a set of uniquely configured photodiodes, and a pair of lenses molded into the package. The lens over the LED focuses light onto the codewheel or codestrip. Light is either reflected or not reflected back to the lens over the photodetector IC. As the codewheel rotates or codestrip passes by, an alternating pattern of light and dark corresponding to the pattern of the codewheel falls upon the photodiodes. This light is used to produce internal signals A and A, and B and B. As part of this “push-pull” detector system, these signals are fed through comparators to produce the final outputs for channels A and B. 3 Definitions Pulse Width (P): The number of electrical degrees that an output is high during one cycle, nominally 180°e or 1/2 a cycle. Count (N): For rotary motion, the number of bar and window pairs or counts per revolution (CPR) of the codewheel. For linear motion, the number of bar and window pairs per unit length (lines per inch [LPI] or lines per mm [LPmm]). Pulse Width Error (∆P): The deviation in electrical degrees of the pulse width from its ideal value of 180°e. State Width (S): The number of electrical degrees between a transition in the output of channel A and the neighboring transition in the output of channel B. There are 4 states per cycle, each nominally 90°e. One Cycle (C): 360 electrical degrees (°e), 1 bar and window pair. One Shaft Rotation: 360 mechanical degrees, N cycles (rotary motion only). State Width Error (∆S): The deviation in electrical degrees of each state width from its ideal value of 90°e. Line Density: The number of reflective and non-reflective pairs per unit length, expressed as either lines per inch (LPI) or lines per mm (LPmm). RADIAL HEDR-8000 HEDR-8000 SHAFT SHAFT CODEWHEEL CODEWHEEL C ALL FOUR STATES (S1 TO S4) ARE MAINTAINED. CH. A AMPLITUDE S1 S2 S3 S4 φ CH. B CODEWHEEL ROTATION OR LINEAR MOVEMENT Direction of Rotation: When the codewheel or codestrip moves in the direction from pin 1 to pin 4, as viewed when looking down on the lenses, channel B will lead channel A. If the codewheel or codestrip moves in the opposite direction, channel A will lead channel B. Optical Radius (Rop): For rotary motion, the distance from the codewheel’s center of rotation to the center line connecting the two lenses of the encoder. Specular Reflectance (Rf): a measure of a surface’s reflective finish. This is quantified by the amount of light reflected when hit with an incident beam. A device called a scatterometer is used to quantify specular reflectance on a percent scale. (Contact factory for more information.) Output Waveforms P Phase Error (∆φ): The deviation in electrical degrees of the phase from its ideal value of 90°e. Gap (G): The distance from the top of the package to the surface of the reflective codewheel or codestrip. EA TANGENTIAL φ): The number of Phase (φ electrical degrees between the center of the high state on channel A and the center of the high state on channel B. This value is nominally 90°e. Radial and Tangential Misalignment Error (ER, ET): For rotary motion, mechanical misalignment in the radial and tangential directions relative to the codewheel. Angular Misalignment Error (EA): angular misalignment of the sensor in relation to the tangential direction. This applies for both rotary and linear motion. 4 Absolute Maximum Ratings Storage Temperature, TS Operating Temperature, TA Supply Voltage, VCC Output Voltage, VO Output Current per Channel, IOUT -40°C to 85°C -10°C to 85°C -0.5 V to 7 V -0.5 V to VCC -1.0 mA to 5 mA Note: Exposure to extreme light intensity (such as from flashbulbs or spotlights) can cause permanent damage to device. Recommended Operating Conditions Parameter Temperature Supply Voltage LED Current Symbol TA VCC ILED Load Capacitance Count Frequency Radial Misalignment CL f ER Tangential Misalignment ET Angular Misalignment Codewheel or Codestrip Gap EA G G Codewheel or Codestrip Specular Reflectance Codewheel/Codestrip Tilt Codewheel/Codestrip Resolution Rf CT LPmm (LPI) LPmm (LPI) Min. -10 4.5 13 Typ. 5.0 15 Max. 85 5.5 18 100 15 ± 0.38 (± 0.015) ± 0.38 (± 0.015) 0 ± 1.5 1.52 2.03 2.54 (0.060) (0.080) (0.100) 1.02 1.52 2.03 (0.040) (0.060) (0.080) 60% 0 2.76 (70) 1 2.95 (75) Units °C Volts mA pF kHz mm (in.) mm (in.) deg. mm (in.) mm (in.) Ripple < 100 mVp-p See “Current Limiting Resistor for LED” 2.7 KΩ Pull-Up Velocity (rpm) x N/60 HEDR-8000 HEDR-8010 HEDR-8100 As Measured on TMA µscan Scope (see Note 1) deg. lines/mm (lines/in.) lines/mm (lines/in.) 5.91 150 Notes HEDR-8000 HEDR-8010 HEDR-8100 Notes: 1. Contact factory for more information regarding measurement of specular reflectance. Encoding Characteristics Encoding Characteristics Over the Recommended Operating Conditions and Mounting Conditions. Parameter Pulse Width Error Pulse Width Error (Ch.A,Ch.B) Phase Error Pulse Width Error (Ch.A,Ch.B) Phase Error Symbol ∆P ∆P ∆φ ∆P ∆φ Typical 15 16 10 15,25 12 Maximum 55 75 60 55,75 60 Units °e °e °e °e °e Notes HEDR-8010 HEDR-8100 HEDR-8100 HEDR-8000 HEDR-8000 Note: Typical Value was obtained at typical condition. Maximums were obtained over all range of recommended operating condition and mounting condition. 5 Electrical Characteristics Electrical Characteristics Over Recommended Operating Conditions. Typical Values at 25°C. Parameter Symbol Supply Current High Level Output Voltage Low Level Output Voltage Rise Time ICC VOH VOL tr Fall Time Min. Typ. Max. Units 2.2 5.0 150 0.4 200 mA V V ns 50 60 ns 2.4 tf Notes IOH = -40 µA min. IOL = 3.86 mA CL = 25 pF RL = 2.7 KΩ Current Limiting Resistor for LED A resistor to limit current to the LED is required. The recommended value is 220 Ω (±10%) and should be placed in series between the 5 V supply and pin 8 of the device (VLED). This will result in an LED current of approximately 15 mA. Recommended Codewheel and Codestrip Characteristics Wb Ww Lw ROP Lw Ww Wb Parameter Window/Bar Ratio Specular Reflectance Line Density Window Length Symbol Ww/Wb Rf LPmm (LPI) LPmm (LPI) Lw Min. 0.9 60 – 2.76 (70) 5.91 (150) 1.80 (0.071) Max. 1.1 85 10 2.95 (75) 7.09 (180) 2.31 (0.091) Units lines/mm (lines/inch) lines/mm (lines/inch) mm (inches) Contact factory for further information on compatible codewheel and codestrips. Notes Reflective Bars Non-reflective Bars HEDR-8000 HEDR-8010 HEDR-8100 mm (inches) 6 Mounting Conditions 1 2 3 4 IR Soldering Conditions The following recommended IR soldering profile meets the specifications of the Electronic Industries Association of Japan (EIAJ): 8 7 6 5 1. 150 ±10°C for 90 ±30 seconds 2. Greater than 200°C for 30 ±10 seconds 3. 230°C ±5°C for 10 ±1 second 30 ± 10 S 11.00 mm (0.433 IN.) < ROP < ∞ 2.03 ± 0.51 (0.080 ± 0.020) TEMPERATURE (°C) ROP 10 ± 1 S 235°C MAX. 230°C ± 5°C 200°C 90 ± 30 S 150°C ± 10°C *These dimensions are for HEDR-8000. Please refer to “Recommended Operating Conditions” table for HEDR-8100. RECOMMENDATION: Please refer to Application Note 1079: Design and Performance Considerations with HEDR-8000 for additional product information. TIME (S) 7 Ordering Information A. Modules HEDR-8 OPT 2 00 Resolution Type Lines/Inch 0 = Low resolution 1 = High resolution K = 75 LPI P = 150 LPI Q = 180 LPI Units in Shipping 0 = 50 units (Tube) 2 = 3 units (Tube) 3 = 100 units (Tube-Designers Kit) 4 = 1500 units (Tape and Reel) 5 = 500 units (Tape and Reel) 0 2 3 4 HEDR-8000#2K * * * * HEDR-8100#2P * * * * * * * HEDR-8100#2Q HEDR-8010#2K 5 * B. Codewheel: reflective HEDR-5120 OPT ROP = 11 mm, 2 channels Resolution (Cycle/Rev) Shaft Diameter E = 200 CPR H = 408 CPR 06 = 1/4 in. 1/2 = 6 mm 06 HEDR-5120# * E * H * 12 * In order to achieve the reflective codewheel resolution stated, refer below for suitable encoder recommendation. 1. HEDR-5120#Exx, 200CPR to be used with option K, 75LPI of the encoder. 2. HEDR-5120#Hxx, 408CPR to be used with option P, 150LPI of the encoder.