Small Optical Encoder Modules Technical Data HEDS-9700 Series Features • Small Size • Low Cost • Multiple Mounting Options • Wide Resolution Range • Linear and Rotary Options Available • No Signal Adjustment Required • Insensitive to Radial and Axial Play • -40°C to +85°C Operating Temperature • Two Channel Quadrature Output • TTL Compatible • Single 5V Supply • Wave Solderable Description The HEDS-9700 series is a high performance, low cost, optical incremental encoder module. When operated in conjunction with either a codewheel or codestrip, this module detects rotary or linear position. The A Package Dimensions Mounting Option #50 - Standard (Baseplane Mounting) Contact Factory for Detailed Package Dimensions ESD WARNING; NORMAL HANDLING PRECAUTIONS SHOULD BE TAKEN TO AVOID STATIC DISCHARGE. 2 module consists of a lensed LED source and a detector IC enclosed in a small C-shaped plastic package. Due to a highly collimated light source and a unique photodetector array, the module is extremely tolerant to mounting misalignment. The two channel digital outputs and 5V supply input are accessed through four solder-plated leads located on 2.54 mm (0.1 inch) centers. The standard HEDS-9700 is designed for use with an 11 mm optical radius codewheel, or linear codestrip. Other options are available. Please contact factory for more information. Applications The HEDS-9700 provides sophisticated motion detection at a low cost, making closed-loop control very cost-competitive! Typical applications include printers, plotters, copiers, and office automation equipment. Block Diagram 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 HEDS-9700 is a C-shaped emitter/detector module. Coupled with a codewheel, it translates rotary motion into a two-channel digital output. Coupled with a codestrip, it translates linear motion into a digital output. As seen in the block diagram, the module contains a single Light Emitting Diode (LED) as its light source. The light is collimated into a parallel beam by means of a single lens located directly over the LED. Opposite the emitter is the integrated detector circuit. This IC consists of multiple sets of photodetectors and the signal processing circuitry necessary to produce the digital waveforms. The codewheel/codestrip moves between the emitter and detector, causing the light beam to be interrupted by the pattern of spaces and bars on the codewheel/codestrip. The photodiodes which detect these interruptions are arranged in a pattern that corresponds to the radius and count density of the codewheel/ codestrip. These detectors are also spaced such that a light period on one pair of detectors corresponds to a dark period on the adjacent pair of detectors. The photodiode outputs are fed through the signal processing circuitry. Two comparators receive these signals and produce the final outputs for channels A and B. Due to this integrated phasing technique, the digital output of channel A is in quadrature with channel B (90 degrees out of phase). 3 Output Waveforms A and the neighboring transition in the output of channel B. There are 4 states per cycle, each nominally 90°e. State Width Error (∆S): The deviation, in electrical degrees, of each state width from its ideal value of 90°e. Phase (φ): The number of electrical degrees between the center of the high state of channel A and the center of the high state of channel B. This value is nominally 90°e for quadrature output. Definitions Count (N) = The number of bar and window pairs or counts per revolution (CPR) of the codewheel, or the number of lines per inch of the codestrip (LPI). Pulse Width (P): The number of electrical degrees that an output is high during one cycle. This value is nominally 180°e or 1/2 cycle. 1 Shaft Rotation = 360 mechanical degrees = N cycles 1 cycle (c) = 360 electrical degrees (°e) = 1 bar and window pair 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 Absolute Maximum Ratings Parameter Symbol Min. Max. Units Notes Storage Temperature TS -40 85 °C See Note Operating Temperature TA -40 85 °C See Note Supply Voltage VCC -0.5 7 V Output Voltage VO -0.5 VCC V Output Current per Channel IO -1.0 5 mA 260 °C Soldering Temperature t ≤ 5 sec. Phase Error (∆φ): The deviation of the phase from its ideal value of 90°e. Direction of Rotation: When the codewheel rotates counterclockwise, as viewed looking down on the module (so the marking is visible), channel A will lead channel B. If the codewheel rotates in the opposite direction, channel B will lead channel A. Optical Radius (Rop): The distance from the codewheel’s center of rotation to the optical center (O.C.) of the encoder module. 4 Recommended Operating Conditions Parameter Symbol Min. Max. Units Τ −40 85 °C Supply Voltage VCC 4.5 5.5 V Load Capacitance CL 100 pF 3.2 kΩ pull-up 20 kHz (Velocity (rpm) x N)/60 Temperature Count Frequency Notes Ripple < 100 mVp-p Note: The module performance is guaranteed to 20 kHz but can operate at higher frequencies. Contact factory for more information. Encoding Characteristics Encoding Characteristics over Recommended Operating Range and Recommended Mounting Tolerances. These characteristics do not include codewheel/codestrip contributions. Symbol Typ. Case 1 Max. Case 2 Max. Units Pulse Width Error ∆P 7 30 40 °e Logic State Width Error ∆S 5 30 40 °e Phase Error ∆φ 2 10 15 °e Parameter Notes Case 1: Module mounted on tolerances of ± 0.13 mm (0.005"). Case 2: Module mounted on tolerances of ± 0.25 mm (0.010") Note: See Figures in Mounting Considerations for details on Case 1 and Case 2 mounting tolerances. Electrical Characteristics Electrical Characteristics over Recommended Operating Range, Typical at 25°C. Parameter Symbol Supply Current ICC High Level Output Voltage VOH Low Level Output Voltage VOL Min. Typ. Max. Units 17 40 mA 2.4 0.4 Notes V IOH = -40 µA V IOL = 3.2 mA Rise Time tr 200 ns CL = 25 pF, RL = 11 kΩ Fall Time tf 50 ns CL = 25 pF, RL = 11 kΩ 5 Recommended Codewheel and Codestrip Characteristics Parameter Symbol Min. Max. Window/Bar Ratio Ww/Wb 0.7 1.4 Window Length (Rotary) Lw 1.80 (0.071) 2.30 (0.091) mm (inch) Absolute Maximum Codewheel Radius (Rotary) Rc Rop + 3.40 (Rop + 0.134) mm (inch) Center of Post to Inside Edge of Window W1 1.04 (0.041) mm (inch) Center of Post to Outside Edge of Window W2 0.76 (0.030) mm (inch) Center of Post to Inside Edge of Codestrip L 3.60 (0.142) A Optional Packages Available Mounting Option #51 – Rounded Outline (Baseplane Mounting) Units mm (inch) Notes Includes eccen– tricity errors 6 A Optional Packages Available (cont'd.) A Mounting Option #52 – Backplane (Backplane Mounting) Mounting Option #53 – Standard with Posts (Baseplane Mounting) 7 A Optional Packages Available (cont'd.) A Mounting Option #54 – Tabless (Baseplane Mounting) Mounting Option #55 – Backplane with Posts (Backplane Mounting) 8 Bent Lead Option Mounting Considerations Note: These dimensions include shaft end play and codewheel warp. All dimensions for mounting the module and codewheel/codestrip should be measured with respect to the two mounting posts, shown above. Mounting Tolerances Case 1 and Case 2 specify the mounting tolerances required on Rm in order to achieve the respective encoding characteristics shown on page 4. The mounting tolerances are as follows: Case 1: Rm ± 0.13 mm (.005 inches) Case 2: Rm ± 0.25 mm (.010 inches) Recommended Screw Size: M2.5 x 0.45 or 2-56 9 Recommended Wave Solder Conditions Flux – RMA Water Soluble (per MIL-F-14256D) Process Parameters 1. Flux 2. Pre-heat 60 seconds total Nominal preheat temp: 90°C Min: 85°C Max: 110°C 3. Solder Pot Zone Nominal dip in time: 2.5 - 4.5 seconds Min: 2.5 seconds Max: 5 seconds PCB top side: 140 -160°C PCB bottom side: 240 - 260°C 4. Wave Solder 255°C, 1.2 meters/minute line speed 5. Hot Water Wash 1st: 30°C 45 seconds 2nd: 70°C 90 seconds 6. Rinse 1st: 23°C 45 seconds 2nd: 23°C 45 seconds 7. Dry 1st: 80°C 105 seconds 2nd: 95°C 105 seconds Typical Interface CH A HEDS–9700 CH B A HCTL-2016/2020 QUADRATURE DECODER/ COUNTER HOST PROCESSOR 10 Ordering Information HEDS-97 0 – Rotary 2 – Linear Lead Bend 0 – Straight Leads 1 – Bent Leads Option Resolution Options (11 mm optical radius, Rop) K – 96 CPR C – 100 CPR D – 192 CPR E – 200 CPR F – 256 CPR G – 360 CPR H – 400 CPR (Linear) L – 120 LPI M – 127 LPI Contact P – 150 LPI Factory for Other Resolution Options Note: Please contact factory for codewheel and codestrip information. 50 HEDS-9700 HEDS-9701 K C D E F G H L M P K C D E F G H L M P 51 52 53 54 55 * * * * * * * * * * * * * * Mounting Options 50 – Standard 51 – Rounded Outline 52 – Backplane 53 – Standard w/Posts 54 – Tabless 55 – Backplane w/Posts 11 50 HEDS-9720 HEDS-9721 K C D E F G H L M P K C D E F G H L M P 51 * 52 53 54 55 * * * * * * * * * 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 (408) 654-8675 Europe: +49 (0) 6441 92460 China: 10800 650 0017 Hong Kong: (+65) 6271 2451 India, Australia, New Zealand: (+65) 6271 2394 Japan: (+81 3) 3335-8152(Domestic/International), or 0120-61-1280(Domestic Only) Korea: (+65) 6271 2194 Malaysia, Singapore: (+65) 6271 2054 Taiwan: (+65) 6271 2654 Data subject to change. Copyright © 2002 Agilent Technologies, Inc. Obsoletes 5988-5853EN October 2, 2002 5988-8045EN