1. Manuals
  2. Brands
  3. Meerstetter Engineering Manuals
  4. Computer Hardware
  5. LDD-1125
  6. User manual

Meerstetter Engineering LDD-1125 User Manual

Ldd-family, laser diode driver
Hide thumbs Also See for LDD-1125:
Table of Contents

Advertisement

Quick Links

Download this manual
LDD-Family:
LDD-1124
LDD-1121
LDD-1125
Meerstetter Engineering GmbH
Schulhausgasse 12
3113 Rubigen, Switzerland
Meerstetter Engineering GmbH (ME) reserves the right to make changes without further notice to the product described herein. Information
furnished by ME is believed to be accurate and reliable. However typical parameters can vary depending on the application and actual performance
may vary over time. All operating parameters must be validated by the customer under actual application conditions.
User Manual
Laser Diode Driver
SWISS MADE
Phone: +41 31 712 01 01
Email: contact@meerstetter.ch
Website: www.meerstetter.ch

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the LDD-1125 and is the answer not in the manual?

Questions and answers

Subscribe to Our Youtube Channel

Related Manuals for Meerstetter Engineering LDD-1125

Summary of Contents for Meerstetter Engineering LDD-1125

  • Page 1 Website: www.meerstetter.ch Meerstetter Engineering GmbH (ME) reserves the right to make changes without further notice to the product described herein. Information furnished by ME is believed to be accurate and reliable. However typical parameters can vary depending on the application and actual performance...

  • Page 3: Table Of Contents

    Table of Content Overview LDD-1121-based Laser Diode Drivers Introduction to the LDD-Family of Laser Diode Drivers Getting Started, Step-by-Step Software Installation Mounting and Powering-Up the Laser Diode Driver Hardware and Status Verification Laser Diode and Driver Monitoring Configuration Tab 'Settings', Entering New Parameters Operation Control, Driving a Load in CW Operation CW Modulation by Internal Generator Continuous Current Regulation (PID), Output Enabling via USB...

  • Page 4: Overview Ldd-1121-Based Laser Diode Drivers

    1 Overview LDD-1121-based Laser Diode Drivers Mounting (M3-size Bores, 7.5mm in Length): M1: x = 4.0 mm, y = 86.0 mm M2: x = 98.0 mm, y = 86.0 mm M3: x = 4.0 mm, y = 4.0 mm M4: x = 98.0 mm, y = 4.0 mm Power Terminals: M4-size Screws LDD Board Pin Descriptions Platform Bus X3:...

  • Page 5: Introduction To The Ldd-Family Of Laser Diode Drivers

    2x (±16 A / ±19 V), Dual Channel Table A. Overview over the Meerstetter LDD- and TEC-Families of advanced controllers. Meerstetter Engineering GmbH is specialized in supporting custom laser solutions. The present manual covers LDD-Family Firmware and Service Software version 1.50.

  • Page 6: Getting Started, Step-By-Step

    On 64bit versions of Windows 7, the additional installation of vcredist_x64.exe may be necessary: http://www.microsoft.com/download/en/details.aspx?id=13523 The present LDD Service Software is a tool that has been programmed by Meerstetter Engineering for internal use, namely for device configuration, monitoring, and debugging during product development. It is being made available to customers for OEM device evaluation, commissioning and integration LDD Service Software displays 'Device connected, establishing communication…' in the...

  • Page 7: Mounting And Powering-Up The Laser Diode Driver

    Mounting and Powering-Up the Laser Diode Driver Step 3 Mount LDD onto System Carrier Plate Locate the four mounting holes M1-M4 (see Figure 1) • Use M3 size screws to fasten the laser diode driver to the system • For initial tests / operation at low power, placing the LDD on a metal plate / heat sink should be sufficient Connect Laser Diode Driver to Power Supply Step 4 Connect X1 (VIN) and X2 (GND) to the outputs of the external power supply...

  • Page 8: Laser Diode And Driver Monitoring

    Laser Diode and Driver Monitoring Step 10 Check 'Laser Diode Values' with no Laser Diode or Temperature Probe Connected Locate the corresponding group box in Tab1 • Note that current and voltage values are static and close to zero (no LD connected, LDD disabled) Note that laser diode temperature is at end of range (no °...

  • Page 9: Operation Control, Driving A Load In Cw Operation

    *For early evaluation and training purposes, the use of a dummy load over a laser diode is recommended Meerstetter Engineering also encourages you to crosscheck the current and voltage through/across the load with your own instruments. For static CW mode, the use of multimeters is sufficient. For modulated CW and pulsed mode, adequate current probe and oscilloscope will be necessary.

  • Page 10: Continuous Current Regulation (Pid), Output Enabling Via Usb

    Continuous Current Regulation (PID), Output Enabling via USB Step 17 Optimize PID Regulation You want to find PID values that allow the CW current source to follow given nominal • values (internally generated or externally given) as fast and accurately as possible. As for all regulation problems, system tuning depending on the actuator, the feedback, the signal and the load will be a trade-off between speed, precision and stability For the optimization of PID regulation, external online monitoring (oscilloscope, current...

  • Page 11: Ldd Signal Generation And Control Operating Principle

    4 LDD Signal Generation and Control Operating Principle LDD-1121-based laser diode drivers all have a common operating principle. The output current stage consists of power electronics that are modulated by a PID controller. The stage's input can either be an external line, an internal generator or the output of the light control stage (selected models only).

  • Page 12: Ldd Service Software Reference

    5 LDD Service Software Reference Laser Diode Driver Configuration via LDD Service Software Configurations and Parameter Activation When establishing a connection with the laser diode driver, the LDD Service Software reads all current device settings. During operation, the current settings can also loaded manually by clicking the 'Read Config' button.

  • Page 13: Settings Dump (*.Mepar File)

    Settings Dump (*.mepar File) For cases where many or all settings are to be changed from a host software or from a host microcontroller, a Settings Dump functionality is available. TEC Service Software is used to generate a file which can be dumped to TEC controllers using third party host systems. Any information in 'New' fields can be stored to a *.mepar File, which is a text file where every line contains a parameter string that is specific to function, firmware and device type.

  • Page 14: Tab1: Monitor

    Tab1: Monitor Figure 8. Tab1 'Monitor' (laser diode driver running under CW conditions) System Monitoring The LDD Service Software's 'Monitor' tab displays current system status: 'Firmware and Hardware Versions' shows said parameters, the serial number and type should • match the sticker on your device. 'Laser Diode Values' displays current, voltage and temperature.
  • Page 15 'Driver Values' displays device temperature and individual currents flowing through the laser • diode driver's three buck converter channels. Those three currents should be balanced. Current and Voltage Display Smart Selection The most relevant current and voltage values to be displayed in the main 'Laser Diode Values' group box are chosen by smart selection.

  • Page 16: Tab2: Operation Control

    Tab2: Operation Control As described earlier in this manual, each LDD-1121-based laser diode driver has got two stages / operation modes: first a continuous current mode (current-stage) that is PID controlled and can be modulated, then a pulse mode (pulse-stage) in which the CW signal is chopped. For both of these modes, various control sources are available (internal, external, hardware, software).

  • Page 17: Modulated Cw Current (Current-Stage)

    Modulated CW Current (Current-Stage) Input Source: 'CW' • Laser diode driver output current is set to the value 'Current CW'. Input Source: 'Int. Generator' • The internal generator produces a nominal value signal according to the values of 'Current High', 'Current Low' and the high/low and rise/fall times.

  • Page 18: Tab3: Laser Power Control - Lpc [Not On All Models]

    Tab3: Laser Power Control – LPC [NOT ON ALL MODELS] Selected LDD-1121-based laser diode drivers feature laser power metering hardware. On such devices, the amount of currently produced light can be used to closed-loop control the amount of electrical current flowing through the laser diode.

  • Page 19: Step-By-Step Instructions / Check-List Laser Power Control

    Step-by-Step Instructions / Check-List Laser Power Control Make sure the PID current controller (Tab5, 'Settings') is set such that pulses (Tab2, 'Operation • Control') are optimally generated. Please refer to chapter 5.6 for brief information on PID optimization Understand the serial arrangement of the current controller that is instructed by the laser power •...

  • Page 20: Tab4: Chart

    Tab4: Chart The LDD Service Software's charting feature help system monitoring and analysis. All buffers and parameters for charting are stored on the PC running the service software, no configuration is written to the LDD device. Figure 13. Tab4 'Chart' in operation, showcasing the soft-start current limiter for laser power control.

  • Page 21: Tab5: Settings

    Tab5: Settings Figure 14. Tab5 'Settings'. Consult below table for latest default values PID Current Regulation Parameters 3 %/A 0.001 s 1E-09 s Analog Control Current Factor 1 A/V Maximum Values Current Limit Max 1.5 ¦ 15 ¦ 30 A Current Limit Min (not the same for all LDD-Family devices, please refer to the MeCom Document 5130)

  • Page 22: Pid Current Regulation

    PID Current Regulation An LDD-1121-based laser diode driver's current-stage is regulated by a PID controller. For the optimization of PID parameters, external online monitoring (oscilloscope, current probe) is required. Also, starting with a dummy load connected is highly recommended. Depending on the current to be drawn from the laser diode driver, different starting parameter sets are used (see below).

  • Page 23: Remote Control / Bus Control By Communication Protocol 'Mecom

    Ethernet operation requires additional hardware, such as the LTR-1200 Rack Enclosure with HMI. The 'MeCom' protocol is not covered in this manual. Please refer to documents 5117 [general] and 5130 [LDD-Family-specific]). Feel free to contact Meerstetter Engineering if you require the implementation of a customized protocol.

  • Page 24: Laser Diode Temperature Monitoring

    Laser Diode Temperature Monitoring Each LDD-1121-based laser diode driver is factory-set to acquire temperature in the range of 0 to 60° C using a "B 3988K, R 10k" NTC probe. 25/100 'Lower Error Threshold' and 'Upper Error Threshold' define the permitted range of temperature measurement.

  • Page 25: Tab6: Maintenance

    The laser diode driver is designed to accommodate various NTC temperature probes and their characteristics. Three ['Temperature', 'Resistance'] pairs are needed to fix a characteristic curve according to the Steinhart-Hart model. Decide for three temperatures ('Lower Point', 'Middle Point' and 'Upper Point') and look up their corresponding resistances in your NTC sensor's data sheet.

  • Page 26: Remote Control / Service Communication By Ldd Service Software

    Remote Control / Service Communication by LDD Service Software LDD Service Software can address one laser diode driver, even if several devices share a single communication interface. It is also possible, to have one or several TEC-Family Peltier controllers connected to that same bus, and to control them by TEC Service Software. These functionalities can be used as stand-alone, or as complement to an existing 'MeCom' control implementation.
  • Page 27 Bus Operation and Device Addresses On a bus, each device must have a unique identification (Tab 'Operation'). TEC- and LDD-Family devices can be mixed at leisure; unique addresses may range from 1 to 254 (0 and 255 are reserved: all devices respond to calls on these broadcast addresses).
  • Page 28 Resolution of Address Conflicts by Remote Setting of Device Addresses If several devices are attached to one same communication bus, but are not addressable, e.g. due to either address conflict, TEC Service Software allows to change one particular device's address. That device is selected according to its Serial Number and Device Type.

  • Page 29: Ldd-Family Laser Diode Driver Firmware Updates

    LDD-Family Laser Diode Driver Firmware Updates Before updating the firmware of your laser diode driver, back up its current configuration. This is very important because it is possible that the new firmware will have an extended parameter set. By importing the old configuration into an LDD with updated firmware, device-specific parameters from the former set are converted and kept.

  • Page 30: Tab7: Expert

    Temperature sensor characteristics adjustments ('Temperature Offset', 'Temperature Gain') allow for gauging of individual sensors, i.e. differences between different sensor assemblies (probe, cable, connection) can be corrected for. Please contact Meerstetter Engineering if you wish to calibrate temperature acquisition hardware or adjust temperature probe characteristics. Page 30 (36) Laser Diode 23.05.12 US...

  • Page 31: Current Measurement Settings (Current Acquisition System)

    Typically your hardware will have been custom assembled by Meerstetter Engineering to cover for your specific photodiode. The value of 'Measurement Rs' will typically be in the range of a few k .

  • Page 32: Appendix 1 Laser Diode Driver Status Leds And Error Codes

    Appendix 1 Laser Diode Driver Status LEDs and Error Codes System Status LDD devices feature green and status LEDs both for the STM32 microcontroller and for the FPGA. In normal operation, both green LEDs are blinking. In the case of any error occurring, the laser diode driver enters an error status and the red STM32 status LED is lit.
  • Page 33 Error Numbers, Instances and Parameters Error Numbers from 1 through 99 designate error conditions that are universal across the whole • range of Meerstetter advanced laser diode drivers and TEC controllers. Error numbers starting from 100 designate conditions that are specific to LDD-Family devices (see tables below).
  • Page 34 Code Description Error Condition, Remedy PARMETER_READ Internal parameter system malfunction PARMETER_WRITE PAR_LOAD_CRC Parameter set corrupt Configuration flash empty or defect (Remedy: cf. #23) PAR_LOAD_PAR_VERSION Set of parameters incompatible Load .ini file saved prior to FW with current firmware version update, or Default.ini UNKNOWN_DEVICE_TYPE Firmware does not recognize valid device...
  • Page 35 Code Description Error Condition, Remedy FPGA_CRC Wrong checksum for FPGA config Reinstall FW / FPGA config via memory internal bootloader FPGA_GENERAL FPGA malfunction FPGA_VERSION Microcontroller firmware and (Remedy: cf. #70) FPGA configuration incompatible Table R. FPGA Errors Page 35 (36) Laser Diode 23.05.12 US User Manual...
  • Page 36 Error Numbers 100 - … (Specific, for LDD-Family devices) Code Description Error Condition, Remedy PID_LIMIT PWM saturation time > 100 µs (100 x 1 µs), PWM saturation error Check input current is sufficient and V not set too close to V TLD_TEMP_RANGE_UNDER <...

This manual is also suitable for:

Ldd-1124Ldd-1121

Table of Contents