Small Optical Encoder Modules Technical Data HEDS-973x 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 • High Resolution Version of the HEDS-970x • Two Channel Quadrature Output • TTL Compatible • Single 5 V Supply • Wave Solderable Description The HEDS-973x series is a high performance, low cost, optical incremental encoder module. When operated in conjunction 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 with either a codewheel or codestrip, this module detects rotary or linear position. The 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 5 V supply input are accessed through four solder-plated leads located on 2.54 mm (0.1 inch) centers. The standard HEDS-973x is designed for use with an 11 mm optical radius codewheel, or linear codestrip. Other options are available. Please contact factory for more information. Block Diagram Applications The HEDS-973x 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. . 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-973X 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 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. Output Waveforms 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. 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). 1 Shaft Rotation = 360 mechanical degrees = N cycles 1 cycle (c) = 360 electrical degrees (°e) = 1 bar and window pair 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. 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. State Width Error (∆S): The deviation, in electrical degrees, of each state width from its ideal value of 90°e. Optical Radius (Rop): The distance from the codewheel’s center of rotation to the optical center (O.C.) of the encoder module. Angular Misalignment Error (EA ): angular misalignment of the sensor in relation to the tangential direction. This applies for both rotary and linear motion. Mounting Position (RM): Distance from Motor Shaft center of rotation to center of Alignment Tab receiving hole. 4 Absolute Maximum Ratings Parameter Symbol Min. Max. Units 85 °C Storage Temperature TS -40 Operating Temperature TA -40 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 70 85 °C 70 Notes Option A & Q All Other Options Option A & Q All Other Options t ≤ 5 sec. Recommended Operating Conditions Parameter Symbol Min. T -40 Supply Voltage VCC 4.5 Load Capacitance CL Temperature Typ. 5.0 Count Frequency Angular Misalignment EA Mounting Position RM -2.0 0.0 ROP -0.14 (ROP -0.006) Max. Units 85 70 °C Option A & Q All Other Options 5.5 V Ripple < 100 mVp-p 100 pF 3.2 kΩ pull-up 40 kHz (Velocity (rpm) x N)/60 +2.0 deg. mm mm (in.) (inch) Notes Shaft cL 0.13 mm (0.005”) See Mounting Considerations Note: The module performance is specified at 40 kHz but can operate at higher frequencies. Electrical Characteristics Electrical Characteristics over Recommended Operating Range, Typical at 25°C. Parameter Supply Current Symbol Min. ICC High Level Output Voltage VOH Low Level Output Voltage VOL Typ. Max. 17 40 Units Notes Option A & Q mA 57 85 2.4 0.4 All Other Options V IOH = -200 µA V IOL = 3.86 mA Rise Time tr 180 ns C L = 25 pF, Fall Time tf 40 ns RL = 3.3 kΩ pull-up 5 Encoding Characteristics Encoding Characteristics over Recommended Operating Condition and recommended mounting tolerances. These characteristics do not include codewheel/codestrip contribution. The Typical Values are averages over the full rotation of the codewheel. For operation above 40 kHz, see frequency derating curves. Parameter Symbol Typical Maximum Units Pulse Width Error ∆P 5 45 °e Logic State Width Error ∆S 3 45 °e Phase Error ∆φ 2 15 °e Note: 3.3 kΩ pull-up resistors used on all encoder module outputs. Frequency Derating Curves Typical performance over extended operating range. These curves were derived using a 25 pF load with a 3.3 k pull-up resistor. Greater load capacitances will cause more error than shown in these graphs. A B 15 CHANGE IN PULSE WIDTH ERROR (ELECTRICAL DEGREES) CHANGE IN STATE WIDTH ERROR (ELECTRICAL DEGREES) 0 +25 °C +85 °C -5 -40 °C -10 -15 0 50 100 150 FREQUENCY (KHz) 200 -40 °C 10 +25 °C 5 +85 °C 0 -5 0 50 100 150 FREQUENCY (KHz) 200 6 Recommended Codewheel and Codestrip Characteristics Parameter Symbol Min. Max. 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) Window/Bar Ratio Center of Post to Inside Edge of Codestrip L Units 3.60 (0.142) Notes Includes eccen– tricity errors mm (inch) Optional Packages Available (OPTICAL CENTER) GND CH A 3.0 0.118 VCC φ 2.8 0.110 10.8 0.425 CH B 3.8 0.150 0.50 0.020 PIN 1 IDENTIFIER 3.9 0.152 0.14 0.006 2X φ 2.00 0.079 4.2 0.167 7.5 0.295 10.1 0.398 LEAD THICKNESS: 1.7 0.067 3.9 0.154 7.0 0.276 15.0 0.591 1.8 0.071 0.25 0.010 X 51 hp 4.34 0.171 H97X0 6.40 0.252 YYWW • 0.8 0.031 5.5 0.217 20.2 0.795 9.8 0.386 DIMENSIONS ARE MILLIMETERS INCHES Mounting Option #51 – Screwmount (Baseplane Mounting) 12.6 0.496 7 Optional Packages Available (cont'd.) Mounting Option #52 – Backplane (Backplane Mounting) Mounting Option #53 – Standard with Posts (Baseplane Mounting) 8 Optional Packages Available (cont'd.) Mounting Option #54 – Tabless (Baseplane Mounting) Mounting Option #55 – Backplane with Posts (Backplane Mounting) 9 Bent Lead Option Mounting Considerations 4.44 ± 0.13 0.175 ± 0.005 Rm IMAGE SIDE OF CODEWHEEL/CODESTRIP CENTER OF ROTATION MOTOR SHAFT CENTER –A– EA ALIGNMENT TAB RECEIVING HOLE A 0.13 mm (0.005") For linear motion, angular misalignment, EA, must be ≤ ± 2 degrees to achieve Encoding Characteristics. All dimensions for mounting the module and codestrip should be measured with respect to the two mounting posts, shown above. Recommended Screw Size: M2.5 x 0.45 or 2-56 10 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 11 Ordering Information HEDS-973 Lead Bend 0 – Straight Leads 1 – Bent Leads 2 – Straight Leads 3 – Bent Leads Option Resolution Options A – 500 CPR, 11 mm Rop B – 1000 CPR, 11 mm Rop J – 1024 CPR, 11 mm Rop Q – 180 LPI, Linear 2 – 300 LPI, Linear 1 – 360 LPI, Linear T – 2000 CPR, 23.36 mm Rop U – 2048 CPR, 23.36 mm Rop Mounting Options 50 – Standard 51 – Screwmount 52 – Backplane 53 – Standard w/Posts 54 – Tabless 55 – Backplane w/Posts Note: Please contact factory for codewheel and codestrip information. 50 HEDS-9730 A * Q * 2 * 51 52 53 54 55 * * 1 B J HEDS-9731 HEDS-9732/33 A * Q * 2 * * * * * * 1 * * * * * * B * * * * * * J * * * * * * T * * * * * * U * * * * * * 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 5988-5852EN October 2, 2002 5988-8044EN