Agilent HEDS-9710, HEDS-9711 200 lpi Analog Output Small Optical Encoder Modules Data Sheet Description The HEDS-9710/HEDS-9711 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 encoder 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 analog 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-9710/HEDS9711 is designed for use with an appropriate optical radius codewheel, or linear codestrip. Please contact the factory for more information. Features • Small size • Multiple mounting options • 200 lpi resolution • Linear and rotary options available • Insensitive to radial and axial play • 15°C to 45°C operating temperature • Two-channel analog output • Single 5 V supply • Wave solderable Applications The HEDS-9710/HEDS-9711 provides sophisticated motion detection at a low cost, making closed-loop control very costeffective. 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-9710/HEDS-9711 is a C-shaped emitter/detector module. Coupled with a codewheel, it translates rotary motion into a two-channel analog output. Coupled with a codestrip, it translates linear motion into analog outputs. ESD WARNING: NORMAL PRECAUTIONS SHOULD BE TAKEN TO AVOID STATIC DISCHARGE. 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 analog 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, which produces the final outputs for channels A and B. Due to this integrated phasing technique, the analog output of channel A is in quadrature with channel B (90 degrees out of phase). Package Dimensions See HEDS-9700 datasheet for package outline drawings. State Width Error (∆S): The deviation, in electrical degrees, of each state width from its ideal value of 90°e. 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 (LPI) of the codestrip. 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. 1 Shaft Rotation = 360 mechanical degrees = N cycles Phase Error (∆Φ): The deviation of the phase from its ideal value of 90°e. 1 cycle (c) = 360 electrical degrees (°e) = 1 bar and window pair 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. 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. Optical Radius (ROP): The distance from the codewheel’s center of rotation to the optical center (O.C.) of the encoder module. 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 four states per cycle, each nominally 90°e. Mounting Position (RM): Distance from Motor Shaft center of rotation to center of Alignment Tab receiving hole. Absolute Maximum Ratings Parameter Symbol Min. Max. Units Storage Temperature TS –40 85 °C Operating Temperature TA 15 45 °C Supply Voltage VCC –0.5 7 V 260 °C Soldering Temperature Notes t ≤ 5 sec. Recommended Operating Conditions Parameter Symbol Min. Max. Temperature T 15 45 Supply Voltage VCC 4.8 Count Frequency 2 Units Notes 5.2 V Ripple < 100 mVp-p 8 kHz (Velocity (rpm) x N) 60 Waveform Definition ANALOG Iap Ibp A B Iam Ibm DIGITAL A B P P S1 S2 S3 S4 Name Paramenter Analog Peak Definition Label The absolute value in µA of the magnitude of the analog signal (i.e., one-sided reading). Iap, Ibp, Iam, Ibm Iapp Ibpp Analog Peak-to-Peak Ipp The peak-to-peak signal magnitude in µA of the analog signal. Analog Offset Ioffset The offset in µA from the mid-point of the analog peak-to-peak signal to the zero current point. State Width State Width The number of electrical degrees between a transition in channel A and the neighboring transition in channel B. There are four states per cycle, each nominally 90°e. The transitions are determined by where the analog signal crosses the Zero point. State Width Error State Width Error The deviation, in electrical degrees, of each state width from its ideal value of 90°e. Pulse Width Pulse Width The number of electrical degrees that an analog output is greater than zero during one cycle. This value is nominally 180°e or 1/2 cycle. Pulse Width Error Pulse Width Error The deviation, in electrical degrees, of each pulse width from its ideal value of 180°e. State 1 State 2 State 3 State 4 P Electrical Characteristics Electrical Characteristics over Recommended Operating Range, Typical at 25°C. 3 Parameter Symbol Supply Current ICC Min. Typ. Max. Units 17 40 mA Notes Encoding Characteristics Encoding Characteristics over Recommended Operating Range and Recommended Mounting Tolerances. These characteristics do not include codewheel/codestrip contributions. Units Radial microns ± 130 Tangential microns ± 130 Gap microns 50 – 250 Temperature °C 15 – 45 O.R. mm 18 – Linear CPR count 900 – Linear Codewheel Slot/Spoke ratio 0.9 – 1.1 Min. Max. Ipp µA 10 73 Ioffset µA –4 +4 State Width Error e° –40 +40 Pulse Width Error e° –40 +40 Recommended Codewheel and Codestrip Characteristics Parameter Symbol Min. Max. Window/Bar Ratio Ww/Wb 0.9 1.1 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 4 L 3.60 (0.142) Units mm (inch) Notes Includes eccen– tricity errors Analog Encoder Interface Circuit The circuit shown can be used to convert the current output to a voltage. Resistor value, R1, and Capacitor, C, are specified to attain required gain and low-pass filtering, which are application specific. The gain is chosen to attain maximum output swing and not clamp the op-amp. VREF should be set to 1.4 V ± 0.2 V. A 0.1 µF bypass capacitor (decoupling capacitor) is recommended to be placed within 1 cm of the encoder for optimal power supply noise rejection. Outputs are high impedance (typical 1 M ohm) and susceptible to EMI. VREF + I+ VA – C IA-IN R1 VREF + I+ VB – C IB-IN R1 VREF = 1.4 V ± 0.2 V (DC) Ordering Information HEDS-971 5 Option Lead Configurations Resolutions Bracket Options 0 – straight leads 1 – bent leads R – 200 lpi 50 51 Package Dimensions Option 50 LEAD THICKNESS = 0.25 mm LEAD PITCH = 2.54 mm 3.8 PIN 1 ID C 3.9 0.8 2x ∅ 2.00 ± 0.02 1.70 ± 0.15 4.2 10.1 DATE CODE 15.0 3.90 ± 0.10 7.5 12.6 ± 0.5 8.4 PART # (REFER -05) 7.0 YYWW 4.2 XXXXX 5.0 X AGILENT 1.4 6.4 0.14 (OPTICAL CENTER) GND OPTION CODE 50 5.5 ± 0.3 8.7 3.0 R 2.6 CH A R 1.4 VCC CH B 10.8 ± 0.5 0.5 C = COUNTRY OF ORIGIN MARKING (REFER -05 FOR DETAILS) 20.2 ± 0.5 1.8 9.8 Package Dimensions Option 51 LEAD THICKNESS = 0.25 mm LEAD PITCH = 2.54 mm 3.8 GND CH A 3.0 VCC CH B 10.8 ± 0.5 0.5 OPTION CODE 5.5 ± 0.3 PIN 1 ID 3.9 0.14 (OPTICAL CENTER) 0.8 2x ∅ 2.00 ± 0.02 1.70 ± 0.15 4.2 7.5 YYWW 4.2 C 4.34 ± 0.20 X AGILENT 6.4 XXXXX 8.7 8.4 PART # (REFER -05) 3.90 ± 0.10 10.1 9.8 7.0 12.6 ± 0.5 DATE CODE 15.0 20.2 ± 0.5 1.8 51 ∅ 2.8 C = COUNTRY OF ORIGIN MARKING (REFER -05 FOR DETAILS) Package Dimensions Bent Version – Option 50 LEAD THICKNESS = 0.25 mm LEAD PITCH = 2.54 mm 6.0 4.2 3.9 0.14 (OPTICAL CENTER) 0.8 2x ∅ 2.00 ± 0.02 1.70 ± 0.15 4.2 10.1 GND CH A DATE CODE 15.0 3.90 ± 0.10 7.5 7.0 12.6 ± 0.5 8.4 PART # (REFER -05) PIN 1 ID YYWW 5.0 50 AGILENT 9.2 ± 0.3 6.4 VCC OPTION CODE X 1.4 5° TYP. C 8.7 R 1.4 XXXXX R 2.6 CH B 3.0 ± 0.3 C = COUNTRY OF ORIGIN MARKING (REFER -05 FOR DETAILS) 20.2 ± 0.5 1.8 9.8 3.8 0.5 10.8 ± 0.5 Package Dimensions Bent Version – Option 51 LEAD THICKNESS = 0.25 mm LEAD PITCH = 2.54 mm 6.0 0.8 2x ∅ 2.00 ± 0.02 PART # (REFER -05) 3.90 ± 0.10 7.5 10.1 9.8 3.8 0.5 10.8 ± 0.5 PIN 1 ID 7.0 12.6 ± 0.5 DATE CODE 15.0 20.2 ± 0.5 1.8 51 GND 8.4 1.70 ± 0.15 4.2 YYWW 3.9 0.14 (OPTICAL CENTER) C 4.2 4.34 ± 0.20 X AGILENT 9.2 ± 0.3 6.4 XXXXX 8.7 CH A OPTION CODE VCC 5° TYP. ∅ 2.8 CH B 3.0 ± 0.3 C = COUNTRY OF ORIGIN MARKING (REFER -05 FOR DETAILS) 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 specifies 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) Recommended Screw Size: M2.5 x 0.45 or 2-56 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 5988-3614EN May 10, 2002 5988-6261EN