H Optical Reflective Sensors Technical Data HEDS-1200 High Resolution Infrared Sensor HEDS-1300 Precision Resolution Sensor Features Description • Focused Emitter and Detector in a Single Package • TO5 Package • Binning of Sensors by Photocurrent (Ipr) Both the HEDS-1200 and HEDS1300 sensor are fully integrated modules designed for applications requiring optical reflective sensing. The modules contain an LED emitter (at the appropriate wavelengths) and a matched I.C. photodetector. A bifurcated aspheric lens is used to image the active areas of the emitter and the detector to a single spot that defines the resolution of the sensor. The output signal is a current generated by the photodiode. Applications • Bar Code Scanning • Pattern Recognition and Verification • Object Sizing • Optical Limit Switching • Optical/Surface Inspection • Tachometry • Edge/Line Sensing • Dimensional Monitoring Selection Guide Sensor Part Number Resolution LED Wavelength Package Dimensions MAXIMUM SIGNAL POINT – MSP 9.40 (0.370) 8.51 (0.335) HEDS-1200 HEDS-1300 0.13 mm (0.005 in.) 0.19 mm (0.0075 in.) 820 nm 700 nm S.P. 5.08 (0.200) REFERENCE PLANE 12.0 (0.473) R.P. 8.33 (0.328) 7.79 (0.307) CL 1.14 (0.045) 0.73 (0.029) 5.08 (0.200) 4.27 ± 0.25 (0.168 ± 0.010) Z 0.86 (0.034) 0.73 (0.029) 15.24 (0.600) 12.70 (0.500) 11.50 (0.453) 11.22 (0.442) NOTES: 1. ALL DIMENSIONS IN MILLIMETERS AND (INCHES). 2. ALL UNTOLERANCED DIMENSIONS ARE FOR REFERENCE ONLY. 3. THE REFERENCE PLANE (R.P.) IS THE TOP SURFACE OF THE PACKAGE. 4. NICKEL CAN AND GOLD PLATED LEADS. 5. S.P. = SEATING PLANE. 6. THE LEAD DIAMETER IS 0.45 mm (0.018 IN.) TYP. 4-22 5965-5947E Mechanical Considerations The HEDS-1200 and HEDS-1300 sensors are packaged in a high profile 8 pin TO5 metal can with a glass window. The emitter and photodetector chips are mounted on the header at the base of the package. Positioned above these active elements is a bifurcated aspheric acrylic lens that focuses them to the same point. HEDS-1200 Optical System SCHEMATIC DIAGRAM REFLECTOR 8 REFERENCE PLANE Z In applications requiring contact scanning, protective focusing tips are available. Focusing tips are available in either metal (HBCS2999 or HBCS-4999) or polycarbonate (HBCS-A998 or HBCS-A999) packages using a rugged sapphire ball as the contact surface. DP 7 DP LED 6 3 3 LED 5 DS 4 DS 2 4 CASE, SUBSTRATE TOP VIEW PIN # 2 3 4 6 FUNCTION (HEDS-1200) PHOTODIODE ANODE, SUBSTRATE, CASE PHOTODIODE CATHODE LED CATHODE, SUBSTRATE, CASE LED ANODE HEDS-1300 Optical System SCHEMATIC DIAGRAM CONNECTION DIAGRAM TRANSISTOR NOT SPECIFIED Electrical Operations Both the HEDS-1200 and HEDS1300 sensors have the following in common. The detector of the sensor is a single photodiode. The cathode of the emitter is physically and electrically connected to the case-substrate of the device. Applications that require modulation or switching of the LED should be designed to have the cathode connected to the electrical ground of the system. Refer to the Schematic and Connection Diagrams that follow. 1 2 6 The sensors can be rigidly secured by commercially available TO5 style heat sinks, or 8 pin 0.200 inch diameter pin circle sockets. These fixtures provide a stable reference platform for affixing the sensors to a circuit board. CONNECTION DIAGRAM REFLECTOR 8* REFERENCE PLANE Z 1* 7 DP LED 2 6 2 1* LED 8* 3 DS 6 3 5 DS 4 DS 4 *NO CONNECTION TO BE MADE TO PIN 1 AND PIN 8 PIN # FUNCTION (HEDS-1300) 2 3 4 6 PHOTODIODE ANODE PHOTODIODE CATHODE LED CATHODE, SUBSTRATE, CASE LED ANODE TOP VIEW 4-23 Absolute Maximum Ratings @ TA = 25°C Parameter Symbol HEDS- Min. Max. Units Storage Temperature Ts 1200 1300 -40 -40 +75 +75 °C °C Operating Temperature TA 1200 1300 -20 -20 +70 +70 °C °C Lead Soldering Temperature 1.6 mm from Seating Plane 1200 1300 Average LED Forward Current If 1200 1300 Peak LED Forward Current Ifpk Reverse LED Input Voltage Photodiode Bias (Id = 100 µA max) Fig. 260°C for 10 sec. 10 1 1 40 50 mA mA 1200 1300 40 75 mA mA Vr 1200 1300 2.5 5.0 V V Vd 1200 1300 20 20 V V -0.3 -0.3 Notes 3 2 7 7 4 4 5 5 Notes: 1. Caution: The thermal constraints of the acrylic lens will not permit the use of conventional wave soldering procedures. The typical preheat and post-cleaning temperatures and dwell times can subject the lens to thermal stresses beyond the absolute maximum ratings and can cause it to defocus. 2. Derate Maximum Average Current linearly from 65°C by 6 mA/°C [HEDS-1300 only]. 3. Non-linear effects make operation of the HEDS-1200 below 10 mA not advisable. 4. 1 KHz pulse rate, 300 mS pulse width. 5. All voltages referenced to Pin 4. System Electrical/Optical Characteristics @ TA = 25°C Parameter Symbol HEDS- Min. Typ. Max. Units Reflected Photocurrent Ipr 1200 1300 150 150 280 280 650 650 nA nA Quality Factor <Q> 1200 1300 0.82 0.82 0.95 0.95 1.0 1.0 Ke 1200 1300 -0.005 -0.01 1/°C 1/°C d 1200 1300 0.13 0.19 mm mm Maximum Signal Point (MSP) Zm 1200 1300 Effective Numerical Aperture of Detector Lens N.A. 1200 1300 Ipr Temperature Coefficient System Optical Step Response Size (OSR) 4.01 4.01 4.27 4.27 4.62 4.52 Conditions Notes If = 35 mA, Vd = 0 1A, 2, 6 See Binning Table 1B, 2, 6 If = 35 mA mm mm Fig. 1A 1B 6 6 6, 7 6, 7 If = 35 mA 8 8 9A 9B Measured from Reference Plane 4 4 0.3 0.3 Notes: 6. Measured from a reflector coated with 99% diffuse reflective white paint (Kodak 6080) positioned 4.27 mm (0.168 in.) from the sensor’s reference plane. Measured physically is the total photocurrent, Ipt, which consists of a signal (reflected from target) component, Ipr, and a component induced by reflections internal to the sensor (stray), Ips. Ipr = Ipt - Ips. 7. <Q> = Ipr/Ipt 8. Photocurrent variation with temperature follows a natural exponential law: Ip(T) = Ip(To)*exp[Ke(T-To)] 9. OSR size is defined as the distance for the 10%-90% “step” response of Ipr as the sensor moves over an abrupt black-white edge, or from opaque white to free space (no reflection). 4-24 9 9 Detector Electrical/Optical Characteristics @ TA = 25°C Parameter Symbol HEDS- Min. Typ. Max. Units Dark Current Id 1200 1300 50 50 Capacitance Cd 1200 1300 Detector Area Ad 1200 1300 Conditions 1000 1000 pA pA Vd = 5 V, If = 0 Reflection = 0% 100 100 pF pF Vd = 0 V, If = 0 f = 1 MHz 0.16 0.16 sq-mm sq-mm Fig. Notes Fig. Notes Square, with length = 0.4 mm per side Emitter Electrical/Optical Characteristics @ TA = 25°C Parameter Symbol HEDS- Vf 1200 1300 BVR 1200 1300 ∆Vf/∆T 1200 1300 Peak Wavelength λ 1200 1300 Emitting Area Ae 1200 0.0062 sq-cm 0.0889 mm diameter junction (0.0035 in.) 1300 0.0285 sq-cm 0.185 mm diameter junction (0.0073 in.) Forward Voltage Reverse Breakdown Voltage Thermal Coefficient of Vf Bin Table Min. Typ. Max. Units 1.48 1.6 1.7 1.8 V V If = 35 mA V V Ir = 100 µA mV/°C mV/°C If = 35 mA nm nm If = 35 mA 2.5 5.0 -0.91 -1.2 805 680 820 700 835 720 Product Marking Ipr Limits (nA) Bin # Min. Max. 2 3 4 5 6 7 8 150 195 240 288 350 425 515 200 245 293 355 430 520 650 Conditions 3 3 5 5 The photocurrent binning of the sensor is included in the 8-digit code printed on the sensor can. The last digit in the code represents the bin number. ature affects LED efficiency slightly and may cause several percent changes in Ipr). Bin numbers are for “reference only” and do not constitute an absolute guarantee. See Figure 8 for suggestions in the application of photocurrent bins. The output of all LEDs degrades with time, depending on drive conditions and temperature. Test algorithm bins units to the lowest bin number if a unit is in the overlap region. Such units can cross bin boundaries as temperature changes. (Ambient temper- The entire available distribution of parts, appropriately marked, will be shipped. Single bin orders cannot be supplied. 4-25 HEDS-1200 Optical System EMITTER 0.089 mm DIA. JUNCTION SILICON BAFFLE HEDS-1300 Optical System OPTICAL APERTURE BAFFLE EMITTER 0.185 mm DIA. JUNCTION BAFFLE EPOXY SEAL EPOXY SEAL SENSING AREA SENSING AREA GLASS DETECTOR 0.406 mm SQUARE GLASS DETECTOR 0.406 mm SQUARE LENS LENS REFLECTOR REFERENCE PLANE Z REFLECTOR DP REFERENCE PLANE 2 + VF 6 Z 1 LED IF = 35 mA 8 DS IPT 3 DS 4 IPT DP + VF 6 3 LED IF = 35 mA nA-METER DS 4 2 CASE, SUBSTRATE Figure 1A. HEDS-1200 Photocurrent Test Circuit. 4-26 nA-METER SUBSTRATE, CASE IPT = IPR + IPS IPS : MEASURED IN THE DARK IPR : WITH Z = 4.27 mm nA-METER: KEITHLEY MODEL 480 (OR EQUIVALENT) Figure 1B. HEDS-1300 Photocurrent Test Circuit. HEDS-1200 1.7 1.6 1.4 1.3 1.2 1.0 0.9 0.6 0.2 85 °C 0 600 700 800 900 WAVELENGTH – nm WAVELENGTH – nm Figure 5. Typical Spectral Distribution of LEDs. Figure 6. Relative Spectral Response of HEDS-1200 and HEDS-1300 Sensors. 1.3 1.2 1.1 1.0 HEDS-1200 ONLY 1 10 100 z 0.2 1.4 1000 z LOW-PASS FILTERING OF AMBIENT LIGHT CAUSED BY RED LENS HEDS-1300 ONLY 1.5 300 H 0.4 1.7 1.6 100 H 0 600 640 680 720 760 800 840 880 920 TYP. PEAK RESPONSIVITY Re = 0.34 AMP/WATT 3 KHz 0.2 0.8 1.9 1.8 1 KHz 0.4 6.5 DISTANCE FROM REFERENCE PLANE OF SENSOR – mm Figure 4. Photocurrent Variation with Distance. 1.0 0.6 HEDS-1300 0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 IFPK (MAX.) RATIO OF MAXIMUM OPERATING PEAK IF (MAX.) CURRENT TO TEMPERATURE DERATED MAXIMUM DC CURRENT 25 °C 0.8 70 °C 0.4 10 KHz RESPONSE @ GIVEN WAVELENGTH NORMALIZED TO PEAK HEDS-1200 -40 °C 25 °C 0.6 10 µA 100 µA 1 mA 10 mA 100 mA Figure 3. LED Forward Voltage vs. Forward Current. 0 °C 1.0 0.8 30 KHz LIGHT OUTPUT (NORMALIZED TO 25 °C VALUE) 1.2 HEDS-1200 IF – FORWARD CURRENT (LOG SCALE) Figure 2. Relative Reflected Photocurrent. HEDS-1300 HEDS-1200 1.1 IF – LED FORWARD CURRENT – mA 1.4 HEDS-1300 1.5 0.8 1 µA 5 10 15 20 25 30 35 40 45 50 0 PHOTOCURRENT NORMALIZED TO PEAK @ MSP 1.8 HEDS-1300 VF – FORWARD VOLTAGE – V PHOTOCURRENT NORMALIZED AT IF = 35 mA, TA = 25 °C 1.5 1.4 1.3 1.2 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 HEDS-1200 MSP RANGE HEDS-1300 MSP RANGE 1.0 10,000 tP – PULSE DURATION (µs) Figure 7. Sensor Pulse Drive Considerations. Max Tolerable Peak Pulse Current vs. Pulse Duration. REFLECTOR REFERENCE PLANE Z RF IF IPT DP NOTE: FOR VO (APPROX.) 1.9 – 2.4 VOLTS SENSOR RECOMMENDED VALUE BIN NUMBER OR RF (OHMS) +5 V 3 6 – LED + DS 2 4 CASE, SUBSTRATE VO VO = RF x |IPT| 2 3 4 5 6 7 8 15 M 12 M 10 M 8.2 M 6.8 M 5.6 M 4.7 M Figure 8. Sensor with Transimpedance Amplifier. 4-27 d – SYSTEM RESPONSE – mm NORMALIZED SIGNAL 1.0 Preferred Orientation 0.8 0.6 d 10 % 0 BLACK NON-PREFERRED ORIENTATION 0.4 0.2 PREFERRED ORIENTATION 0 2.5 3.0 3.5 4.5 4.0 5.0 5.5 DISTANCE FROM REFERENCE PLANE OF SENSOR – mm 1.0 0.8 NON-PREFERRED ORIENTATION 0.6 NORMALIZED SIGNAL Figure 9A. HEDS-1200 System Optical Step Response Variation with Distance. d – SYSTEM RESPONSE – mm At maximum signal point (MSP) and/or when the sensor is in focus, the orientation of the sensor is unimportant. However, as one moves away from MSP and/or moves out of focus (either by distance or angle), the preferred orientation indicated above is recommended to maintain a higher resolution spot size. 100 % WHITE 90 % 100 % WHITE 90 % d 10 % 0 BLACK 0.4 0.2 PREFERRED ORIENTATION 0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 DISTANCE FROM REFERENCE PLANE OF SENSOR – mm Figure 9B. HEDS-1300 System Optical Step Response Variation with Distance. 4-28 Warranty and Service HP Optical Reflective Sensor is warranted for a period of one year after purchase covering defects in material and workmanship. Hewlett-Packard will repair or, at its option, replace products that prove to be defective in material or workmanship under proper use during the warranty period. NO OTHER WARRANTIES ARE EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. HEWLETT-PACKARD IS NOT LIABLE FOR CONSEQUENTIAL DAMAGES. For additional warranty or service information please contact your local Hewlett-Packard sales representative or authorized distributor. 4-29