PLD WAVELENGTH | Alldatasheet

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ORDERING INFORMATION

PLD200 200 mA Laser Diode Driver PLD500 500 mA Laser Diode Driver PLD1250 1.25 A Laser Diode Driver PLD5000 5.0 A Laser Diode Driver PLD6500 6.5 A Laser Diode Driver PLDEVAL Evaluation board for PCB-mounted PLD drivers RELIABILITY YOU CAN TRUST The PLD Series Laser Diode Drivers deliver the reliability and performance you expect from a Wavelength Electronics laser driver in a compact and easy-to-integrate package. Tens of thousands of PLD drivers are deployed in particle counters, manufacturing vision systems, wavefront scanners, fiber aligners, and other laser systems around the world, proving beyond doubt the reliability and stability of the design. DESIGNED FOR EASY INTEGRATION The PLD drivers operate from a single 5 V power supply. To accommodate high compliance lasers, or multiple stacked lasers, the PLD laser diode drivers allow the laser to be driven from a separate power supply up to 30 V. LASER SAFETY FEATURES Built-in safety features make your product more robust to real world operating conditions: latching current limit switches off the output if the current limit is reached; slow start circuit ramps the output current; and a mechanical shorting relay protects the laser from ESD events. Long-term reliability means better up-time, fewer service calls, and more customers who are satisfied with your products. HIGH OUTPUT CURRENT The PLD Series is available up to 12.5 A drive current. Check our website, or call and ask for information about the PLD10000 and PLD12500. FEATURES AND BENEFITS

  • Models: 200 mA, 500 mA, 1.25 A, 5 A, and 6.5 A
  • Operates from a 5 VDC supply
  • Separate power supply can be used to drive high-compliance lasers up to 28 V
  • Constant Current or Constant Power modes
  • Safety features protect your laser » Adjustable latching current limit » Slow-start circuitry » Relay shorts output when current is disabled
  • Local and Remote Power-On and Enable controls
  • Integral heatsink and fan on high current models

CONTENTS

ELECTRICAL SPECIFICATIONS 6 SAFETY INFORMATION 7 OPERATING INSTRUCTIONS 8 ADDITIONAL TECHNICAL INFORMATION 14 TROUBLESHOOTING 19 MECHANICAL SPECIFICATIONS 20 CERTIFICATION AND WARRANTY 21 e PAGE Pb RoHS Compliant Applies to Product Revisions A – H © May 2019 406-587-4910 www.teamWavelength.com PLD Series Laser Diode Drivers DATASHEET AND OPERATING GUIDE

Limit adjust trimpots, status LEDs, and pins. and external electronics to operate a Type A or B laser. types refer to the Operating Instructions. Figure 1. PLD Driver Controls is enabled; Doing so may damage the laser diode.

5 VDC

independently of each other. Figure 2. Quick Connect Wiring Diagram, Type A & B Laser Diodes Figure 3. Laser Type Diagrams

Figure 4. Constant Current Mode Laser Test Loads

Table 1. Pin Descriptions 1 Aux V+ For TYPE C Laser Diodes only. See Figure 11 on page 11. 2 PD Aux For TYPE C Laser Diodes only. See Figure 11. 3 LD Enable Output Enable. Disable = ground or floating. Enable = 3 to 5 V. Requires 5 mA input current. Not TTL-compatible.

4 LIM I Status

Status output pin. Indicates if the driver has reached current limit and has switched off the output. normal operation. Toggle LD Enable to reset the limit circuit and enable the output current.

5 LIM I Monitor

Current Limit Monitor. Transfer function varies by model—refer to Table 2. limit level. Instructions for fine-tuning the current limit are on page 14. 6 Common Measurement ground. Low current return used only with Monitor pins and Analog Input. Internally shorted to GND (pin 11).

7 I Monitor

Laser Diode Output Current Monitor. Transfer function varies by model—refer to Table 2. Range 0 to 2.5 V. Impedance 1 kΩ. NOTE: I Monitor signal has artificial 20 mV offset. Subtract 20 mV for accurate reading. setting—refer to Table 2. Range 0 to 2.5 V. Impedance 1 kΩ.

9 Analog Input

onboard setpoint value. See Electrical Specifications for damage threshold information. supply must be rated to source at least 1.1-times the laser current plus the PLD quiescent current. 11 GND Power supply ground. Used with +5 V for high current return.

12 LD Anode /

Laser Diode Anode connection. Also used as power supply input for high-compliance lasers. Maximum input voltage 30 VDC. 13 LD Cathode Laser Diode Cathode connection. lasers; see Figure 11 on page 11. 15 PD Cathode Photodiode Cathode connection only for Type C lasers. See Figure 11. Table 2. Current Output Monitor, Limit Monitor, Photodiode Current Monitor, and Note: High Range is not available when using Type C Lasers.

© 2019 www.teamWavelength.com 6 PLD SERIES LASER DIODE DRIVER ELECTRICAL SPECIFICATIONS PARAMETER SYMBOL MIN TYP MAX UNIT NOTE ABSOLUTE MAXIMUM RATINGS Supply Voltage +5 V 5.0 to 5.5 VDC Supply Voltage, LDA High Compliance LD Anode 3.0 to 30 VDC Consult Safe Operating Area calculator for supply voltages > 5 VDC; see page 18. Supply Voltage, Type C Lasers Aux V+ 8.0 to 12.5 VDC Operating Temperature Range TOPR 0 to 50 ºC Storage Temperature Range TSTG -55 to 125 ºC Weight < 0.3 lbs Size PLD200 PLD500 PLD1250, PLD5000, PLD6500 1.52 x 2.65 x 0.81 1.52 x 2.65 x 1.10 1.52 x 2.65 x 1.82 in 38.6 mm x 67.3 mm x 20.6 mm 38.6 mm x 67.3 mm x 27.9 mm 38.6 mm x 67.3 mm x 46.3 mm MODEL PARAMETER PLD200 PLD500 PLD1250 PLD5000 PLD6500 UNIT DRIVE CURRENT OUTPUT Max Internal power Dissipation 3 9 45 45 45 W Compliance Voltage 3 V max with 5 VDC power supply voltage

28 V max with 30 VDC power supply voltage V

Short Term Stability, 1 hour < 100 < 100 < 100 < 200 < 200 ppm Quiescent Current 50 50 250 250 250 mA Temperature Coefficient < 200 ppm / ºC Leakage Current 0 mA PHOTODIODE FEEDBACK High Range 50 – 5000 µA Low Range, Type A & B Lasers Only 15 – 500 µA Constant Power Mode Output Stability < 0.02 % EXTERNAL MODULATION Analog Input Damage Threshold (VIN < -0.5) or VIN > (0.5 V above Supply Voltage on Pin 10) V Input Pin Impedance 1 MΩ 3 dB Bandwidth, Constant Current2, max current 190 200 200 140 100 kHz Depth of Modulation at 100 kHz3 90 % Rise / Fall Time 5 / 3 5 / 3 5 / 3 4 / 3 12 / 5 µsec TIMING CHARACTERISTICS 4,5 Output Turn-On Delay ≥1.5 seconds Slowstart Output On-Time 250 msec Disable Fall Time >100 µsec MONITOR ACCURACY Monitor Voltage vs. Expected Output based on transfer function 2 % of Full Scale 1. In order to drive full current to the laser, the supply voltage may need to be increased to 5.5 V to compensate for voltage drop across the cables at high current. 2. Modulation bandwidth in Constant Power mode will depend on the photodiode frequency response. Photodiode specifications vary widely from one manufacturer to another, but the bandwidth in CP mode is typically 10% of the Constant Current bandwidth. 3. Peak-to-Peak output amplitude decreases as frequency increases; see figure at right. 4. See page 17 for timing graphs. 5. See page 16 for PLD Revision F timing characteristics. 0 mA Full Current 100% Depth of Modulation at 10 Hz 100 % 0 % 90% Depth of Modulation at 100 kHz 90 % 95 % 5 %

© 2019 www.teamWavelength.com 7 PLD SERIES LASER DIODE DRIVER SAFETY INFORMATION SAFE OPERATING AREA — DO NOT EXCEED INTERNAL POWER DISSIPATION LIMITS Before attempting to operate the PLD driver, it is imperative that you first determine that the unit will operate within the Safe Operating Area (SOA). Operating outside of the SOA may damage the laser and the PLD. Operating outside of the SOA will void the warranty. To determine if the PLD driver is suitable for your application and if it will be operating in the safe range, consult the instructions for calculating the Safe Operating Area on-line: www.teamwavelength.com/support/design-tools/soa-ld-calculator SOA charts are included in this datasheet for quick reference (page 18 ), but we recommend you use the on-line tools instead. To ensure safe operation of the PLD driver, it is imperative that you determine if the unit is going to be operating within the internal heat dissipation Safe Operating Area (SOA). If you have any questions about the Safe Operating Area calculator, call the factory for free and prompt technical assistance. THEORY OF OPERATION The PLD Series drivers are controlled current sources: they deliver the current commanded by the setpoint. The current source continually monitors the actual output current, compares it to the setpoint, and adjusts the current if there is a difference between the two signals. It may be useful to remember that you do not directly set the drive current setpoint; instead, you adjust a voltage signal that represents the output current. The voltage and output current are related by a transfer function that varies by driver model number. The setpoint voltage is adjusted with the onboard trimpot or by an external input that sums with the onboard setpoint. The adjustable current limit is set in a similar manner. As current is driven through the load, there is a voltage drop across the load because of the impedance. As the current increases, the voltage drop may increase to the point that it reaches the Compliance Voltage limit of the current source. Once that occurs, the current source is no longer able to increase the current driven to the load even if you increase the setpoint. The PLD driver includes features that help protect your laser and make the driver more versatile in a wide array of applications:

  • The user-adjustable latching current limit protects the laser from over-current situations by switching off the output when a limit condition is detected. Toggling the Enable resets the current limit circuit.
  • Output current switches on after approximately 1.5 seconds from the time the Enable signal is applied.
  • Output slow-start ramps the current to setpoint over 250 msec.
  • A mechanical relay shorts the output connections when the output is disabled, and when the PLD driver is powered off.

© 2019 www.teamWavelength.com 8 PLD SERIES LASER DIODE DRIVER OPERATING INSTRUCTIONS The PLD requires minimal external electronics. If you are using the driver on the benchtop or for prototyping your laser control system, we recommend purchasing the PLDEVALPCB board. The driver is first configured for local control in order to set the drive current limit. Then the driver is reconfigured according to the actual application. We recommend using a test load until you are familiar with operation of the driver. Refer to page 3 for test load schematics. NECESSARY EQUIPMENT The following equipment is the minimum necessary to configure the PLD for basic operation:

  • PLD controller
  • PLDEVALPCB evaluation board (recommended)
  • Digital voltmeter, 4-½ digit resolution recommended
  • Test load for configuring the driver
  • Laser diode, mount, and temperature control system
  • Connecting wires
  • Power supply (see below) POWER SUPPLY REQUIREMENTS Linear-regulated or low-noise switching power supplies can be used. We recommend using power supplies with noise specifications suitable for your application. For single-supply operation:
  • 5 VDC power supply rated for 1.1-times the maximum laser diode current, plus 50 – 250 mA for the electronics (see Electrical Specifications) For two-supply operation to drive a high-compliance laser:
  • 5 VDC power supply rated for 50 – 250 mA
  • Power supply rated for 1.1-times the maximum laser diode drive current and > 2 V greater than the compliance voltage of the laser. For Type C lasers:
  • 8 to 12 VDC power supply rated for 50 – 250 mA, plus 1.1-times the maximum laser diode drive current; power regulation circuitry is also required (see Figure 10)
  • OR, a 5 VDC power supply for the PLD driver electronics (rated for 50 – 250 mA) and an 8 to 12 VDC power supply for the laser, rated for 1.1-times the maximum laser diode current SAFE OPERATING AREA AND THERMAL DESIGN CONSIDERATIONS SOA charts are included in this datasheet for quick reference, but we recommend you use the on-line tools instead. www.teamwavelength.com/support/design-tools/soa-ld-calculator It is imperative that you verify the unit will operate within the internal heat dissipation Safe Operating Area (SOA). Operating the driver outside the SOA may damage or destroy the driver and/or laser. PREVENT DAMAGE FROM ELECTROSTATIC DISCHARGE Before proceeding, it is critical that you take precautions to prevent electrostatic discharge (ESD) damage to the driver and your laser. ESD damage can result from improper handling of sensitive electronics, and is easily preventable with simple precautions. Enter the search phrase “ ESD Precautions for Handling Electronics” in an internet search engine to find information on ESD-safe handling practices. We recommend that you always observe ESD precautions when handling the PLD driver and your laser diode.

seating the PLD on the board. pins to the PLDEVALPCB board. jumper bars. Refer to Figure 7.

  • Laser Type-Select Jumper . Remove the jumper for Type A/B laser operation. Install the jumper to tie pin 14 to pin 2 for Type C laser operation. The factory default configuration is with the jumper removed.
  • LD Power Supply Jumper . To operate the PLD and laser from a single 5 VDC power supply, install this jumper. If you are operating a high-compliance laser with a separate power supply, remove the jumper. The factory default configuration is with the jumper installed. PD CATHODE PD ANODE LD CATHODE LD ANODE/ +LD SUPPLY +5V P MONITOR I MONITOR COMMON LIM I MONITOR LIM I STATUS GND INPUT +5 VDC COMMON MONITOR+ LIM I MON LASER DISABLE LASER ENABLE I MONITOR P MONITOR POWER ON ON OFF ANALOG INPUT LD ENABLE PD AUX AUX V+ Power ON OFF 2.5 mm Power Input Jack Internally Connected to Pins 10 and 11; Use with PWRPAK-5V power supply Output Current DISABLE ENABLE Monitor Select PD CURRENT CURRENT Laser-Type Jumper Power Supply Jumper Test Points Power-On LED (Green = ON) Electronics avelength PLD SERIES P L PD RANGE H I MODE LASER DIODE DRIVER OUTPUT ADJUST LIMIT I ADJUST OUTPUT ENABLED LIMIT I Use minimum 22 AWG wire for connections to screw terminals.

Figure 7. PLDEVALPCB Evaluation Board configuration. For setup and configuration use a test load. on the PLDEVALPCB board or installed on a circuit board. Table 3. Wiring Configurations

independently of each other. Figure 8. Type A & B Laser Diode, Single 5 VDC Power Supply

30 VDC

This circuit shows how to use a single power supply. with a separate 5 VDC power supply. must float independently of each other. Figure 9. Type A & B Laser Diode, High-Compliance Laser Diode

float independently of each other. Figure 10. Type A & B Laser Diode, Negative Power Supply Operation

12 VDC

This circuit shows how to use a single power supply. with a separate 5 VDC power supply. required and must float independently of each other. Figure 11. Type C Laser Diode

is enabled; Doing so may damage the laser diode. Figure 12. PLD Driver Adjustments and Controls requires a photodiode feedback loop from the laser diode. may be damaged or destroyed.

  • L (left) = Low Range, PD current 15 – 500 µA
  • H (right) = High range; PD current 50 – 5000 µA Do not switch the PD Range while the output is enabled and driving a laser diode. The laser diode may be damaged or destroyed. CALCULATE THE MONITOR VOLTAGES Refer to the datasheet for your laser to determine the maximum forward current, and calculate the LIM I Monitor voltage using this equation and the transfer function found in Table 2 on page 5: VLIM I Mon = ILIMIT / Transfer Function If you are using the PLD in Constant Current mode, calculate the monitor voltage for the drive current setpoint. Refer to the datasheet for your laser to determine the nominal forward current, and calculate the I Monitor voltage using the transfer function found in Table 2: VI_MON = ILD / Transfer Function If you are using the PLD in Constant Power mode, calculate the P Monitor voltage. Refer to the laser diode datasheet to determine the nominal photodiode current at the desired operating point. Calculate the P Monitor voltage using the transfer function found in Table 2: VP_MON = IPD / Transfer Function SET THE CURRENT LIMIT Connect the positive lead of the digital voltmeter to the LIM I Monitor terminal or evaluation board test point, and the negative lead to the COMMON terminal. Reference Figure 7 for switch and control locations on the PLDEVALPCB board. Configure the PLD and PLDEVALPCB board:
  • Set the OUTPUT switch to LASER DISABLE
  • Set the POWER switch to ON
  • Set the MONITOR switch to I MONITOR
  • Set the OUTPUT ADJUST trimpot to zero by turning at least 12 turns counter-clockwise.
  • Set the current limit by turning the LIMIT I ADJUST trimpot until the voltage displayed on the multimeter matches the value calculated above. Switch off power on the evaluation board, then switch off the power supply. The PLD controllers trip the current limit circuit below the expected limit level, by 0.2 V on the monitor. To trip the current limit at exactly the desired current level, refer to Set the Current Limit More Accurately on page 14 to fine-tune the current limit.

© 2019 www.teamWavelength.com 13 PLD SERIES LASER DIODE DRIVER ADJUST THE OUTPUT CURRENT SETPOINT— ONBOARD CONTROL To increase the output current, turn the onboard trimpot clockwise; turn counter-clockwise to decrease output current. While adjusting the output current, measure the voltage on pin 7, I Monitor. Use the transfer function listed in Table 2 to determine the output current from the monitor voltage. ADJUST THE OUTPUT CURRENT SETPOINT— ANALOG INPUT To use the Analog Input on pin 9 to adjust the output current, refer to Pin Descriptions on page 5 for specifications. The analog input signal sums with the onboard trimpot value. Refer to the External Setpoint Circuit on page 15 for an example analog input circuit. Other circuits, a DAC signal, or function generator may be used. COMBINING THE ONBOARD SETPOINT AND ANALOG INPUT The Analog Input voltage signal on pin 9 sums with the onboard trimpot setpoint. This configuration allows the driver to be configured so that the laser current or power modulates around a DC setpoint. If the sum of the two signals causes the PLD to attempt to drive the output current past the limit, the output will switch off and indicate a current limit error. To avoid driving the current to the limit, first set the onboard trimpot to produce the Constant Current level. Then connect the modulation source to the Analog Input pin and slowly increase the modulation amplitude. Monitor the output current using the I Monitor pin, or by measuring the voltage across the test load. Do not monitor the voltage across a laser diode—measurement transients may damage the laser diode. CURRENT LIMIT CIRCUIT TRIGGER AND RESET If the PLD detects current limit, the output will switch off and the LIMIT I LED on the top of the unit will illuminate red. Set the Enable switch to OFF, correct the cause of the error, and then re-enable the output. Toggling the Output Current switch on the PLDEVALPCB board will clear the current limit latch.

Figure 13. Remote LIM I Status LED Then add the Offset to VLIMIT calculated on page 12.

2.5 V * 106

Figure 14. Adjusting the PD Range, between the PD Cathode (pin 15) and AUX V+ (pin 1).

  • Remote Limit Status LED Circuit
  • Set the Current Limit More Accurately
  • Change the Photodiode Range, Type A & B Lasers
  • Change the Photodiode Range, Type C Lasers
  • Change the Analog Input Modulation Transfer Function
  • External Setpoint Circuit
  • Ground the Fan on the PLD1250, PLD5000, and PLD6500
  • Fine Tune Deep Modulation
  • Cable Lengths and High Current
  • Add Laser Diode Protection for Long Cables
  • Additional Noise Filtering
  • Monitor Calibration Circuit
  • Revision F Timing Characteristics
  • Product Variations
  • Output On/Off and Current Limit Timing
  • Safe Operating Area Calculation

Figure 15. Changing the Analog Input current setpoint; refer to Figure 16.

  • V+5V must be at least 1 volt greater than the voltage value of D1.

Figure 16. Trimpot Circuit for Analog Input grounding to ensure safe operation of the PLD and laser. that float independently of each other. supply remain isolated from earth ground. tapped hole in the bottom of the heatsink.

16 V electrolytic capacitor between the power terminals

directly connected at the driver.

© 2019 www.teamWavelength.com 19 PLD SERIES LASER DIODE DRIVER TROUBLESHOOTING PROBLEM POTENTIAL CAUSES SOLUTIONS Driver will not switch on Improperly configured power supply Carefully check the wiring diagram according to Table 3. Output will not enable Remote Enable signal is not correct Refer to the LD Enable specifications in Table 1 and make sure your input enable signal is correct. Laser output power too low in Constant Current mode Laser current setpoint too low Increase the setpoint either by adjusting the I SET trimpot clockwise, or by increasing the signal voltage on the Analog Input (pin 9). Laser current limit too low Refer to page 12 for instructions on setting the laser driver current limit. Laser driver is compliance limited Check the laser diode specifications to determine the forward voltage (VF). Make sure that the PLD is not compliance limited. Refer to the Electrical Specifications table on page 6. If the driver is compliance limited, V LD ANODE may need to be increased. Verify that the PLD will be operating within the Safe Operating Area if VLD ANODE is increased. Laser does not reach desired output in Constant Power mode Current limit too low Check the laser diode datasheet to determine the approximate laser drive current at the desired optical power output level. Then verify that the current limit is set slightly higher than that. See page 12 for instructions on setting the laser driver current limit. Photodiode feedback current is out of range for the PLD Refer to the laser diode datasheet to determine the approximate photodiode (PD) current at the desired output power level. If the PD current exceeds the PLD PD current range, set the PD Range switch to High Range; see page 12.

© 2019 www.teamWavelength.com 21 PLD SERIES LASER DIODE DRIVER CERTIFICATION AND WARRANTY CERTIFICATION Wavelength Electronics, Inc. (Wavelength) certifies that this product met its published specifications at the time of shipment. Wavelength further certifies that its calibration measurements are traceable to the United States National Institute of Standards and Technology, to the extent allowed by that organization’s calibration facilities, and to the calibration facilities of other International Standards Organization members. WARRANTY This Wavelength product is warranted against defects in materials and workmanship for a period of one (1) year from date of shipment. During the warranty period, Wavelength will, at its option, either repair or replace products which prove to be defective. WARRANTY SERVICE For warranty service or repair, this product must be returned to the factory. An RMA is required for products returned to Wavelength for warranty service. The Buyer shall prepay shipping charges to Wavelength and Wavelength shall pay shipping charges to return the product to the Buyer upon determination of defective materials or workmanship. However, the Buyer shall pay all shipping charges, duties, and taxes for products returned to Wavelength from another country. LIMITATIONS OF WARRANTY The warranty shall not apply to defects resulting from improper use or misuse of the product or operation outside published specifications. No other warranty is expressed or implied. Wavelength specifically disclaims the implied warranties of merchantability and fitness for a particular purpose. EXCLUSIVE REMEDIES The remedies provided herein are the Buyer’s sole and exclusive remedies. Wavelength shall not be liable for any direct, indirect, special, incidental, or consequential damages, whether based on contract, tort, or any other legal theory. REVERSE ENGINEERING PROHIBITED Buyer, End-User, or Third-Party Reseller are expressly prohibited from reverse engineering, decompiling, or disassembling this product. NOTICE The information contained in this document is subject to change without notice. Wavelength will not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material. No part of this document may be translated to another language without the prior written consent of Wavelength. SAFETY There are no user-serviceable parts inside this product. Return the product to Wavelength Electronics for service and repair to ensure that safety features are maintained. LIFE SUPPORT POLICY This important safety information applies to all Wavelength electrical and electronic products and accessories: As a general policy, Wavelength Electronics, Inc. does not recommend the use of any of its products in life support applications where the failure or malfunction of the Wavelength product can be reasonably expected to cause failure of the life support device or to significantly affect its safety or effectiveness. Wavelength will not knowingly sell its products for use in such applications unless it receives written assurances satisfactory to Wavelength that the risks of injury or damage have been minimized, the customer assumes all such risks, and there is no product liability for Wavelength. Examples of devices considered to be life support devices are neonatal oxygen analyzers, nerve stimulators (for any use), auto-transfusion devices, blood pumps, defibrillators, arrhythmia detectors and alarms, pacemakers, hemodialysis systems, peritoneal dialysis systems, ventilators of all types, and infusion pumps as well as other devices designated as “critical” by the FDA. The above are representative examples only and are not intended to be conclusive or exclusive of any other life support device.

REVISION HISTORY

DOCUMENT NUMBER: PLD5000-00400 REV. DATE CHANGE P November 2013 Added CE icon and extended warranty Q January

2014 Updated CP test load section

51 Evergreen Drive

Bozeman, Montana 59715 406-587-4910 (tel) 406-587-4911 (fax) Sales & Tech Support sales@teamwavelength.com techsupport@teamwavelength.com