Wavelength Electronics QCL1000 LAB, QCL500 LAB, QCL1500 LAB, QCL2000 LAB User Manual

USER GUIDE

Low-Noise QCL Driver — Laboratory Series

TABLE OF CONTENTS PAGE

GENERAL OVERVIEW 2 SAFETY 3 QUICK CONNECT GUIDE 4 PIN DESCRIPTIONS 6 EXTERNAL MODULATION TRANSFER FUNCTIONS 6 ELECTRICAL SPECIFICATIONS 7 THEORY OF OPERATION 9 OPERATING INSTRUCTIONS (STAND-ALONE) 9 OPERATING INSTRUCTIONS (REMOTE) 17 TROUBLESHOOTING 22 ADDITIONAL TECHNICAL NOTES 25 MECHANICAL SPECIFICATIONS 27 CE DECLARATION OF CONFORMITY 28 WARRANTY & CERTIFICATION 29

ORDERING INFORMATION

PART NO DESCRIPTION

QCL500 LAB 500 mA Low Noise QCL Instrument QCL1000 LAB 1.0 A Low Noise QCL Instrument QCL1500 LAB 1.5 A Low Noise QCL Instrument QCL2000 LAB 2.0 A Low Noise QCL Instrument NOISESCAN Noise Characterization Scan 55-110014 SMA-BNC Cable 55-110015 USB Cable WCB310 Shielded SMA-SMA Cable

QCL TL LOW QCL TL 1500 Resistive Test Load for QCL1500

QCL TL 2000 Resistive Test Load for QCL2000 RCKMT-LAB SNGL 19” Single Unit Rack Mount Kit RCKMT-LAB DUAL 19” Double Unit Rack Mount Kit

INTLK REPL KIT (included with purchase)

Resistive Test Load for QCL500 or QCL1000

Interlock Replacement Kit with BNC terminator and modiﬁ ed D-SUB connector to override interlocks

RoHS

Covered by U.S. Patents 6,696,887; 6,867,644 and 7,176,755. Licensed from Battelle Memorial Institute

Compliant

Applies to Product Revision A

GENERAL OVERVIEW

• Output currents of 500 mA, 1 A, 1.5 A, 2 A

• Low noise: <0.4 A RMS up to 100 kHz (QCL500, typical)

• Compliance voltage is adjustable, 10 to 20 V (NOTE: The unit will only deliver the voltage

that the load requires, up to the compliance voltage limit.)

• Analog modulation up to 2-3 MHz

• Constant Current Mode operation

• Touchscreen with intuitive user interface

• CE compliant, compatible with CDRH laser regulations

• Feature-rich for research projects

» USB and Ethernet interfaces with software

included » Auto voltage/current scan function » Data collection using a computer or USB

ﬂ ash drive » Field upgradeable ﬁ rmware » Sophisticated error handling

THE LOWEST-NOISE DRIVER AVAILABLE

These low noise QCL instruments have the lowest current noise density of any commercially available. Powering your QCL with this patented1 driver gives you narrow linewidth, stable center wavelength, and repeatable scans.

INTUITIVE USER INTERFACE AND SUPERIOR SOFTWARE CONTROL

With Wavelength’s plug and play instrument, you have the ability to quickly set the controls using either the instrument or a remote computer.

PROTECT YOUR QCL INVESTMENT

All the essential control and monitor functions you expect in a Wavelength laser driver are incorporated into this instrument, along with protection circuitry to safeguard your QCL from minor power source faults, over-temperature conditions, and electrical faults.

The soft-clamping current limit can be set without enabling the driver output, and uses a brick-wall never-exceed limit circuit to protect the QCL from potentially damaging overcurrent situations.

» Save and recall functions for speciﬁ c set

ups

• Rack mountable: 2 U height and ½ rack width

• Safety features protect your QCL investment

F E A T U R E S

» Adjustable soft-clamp current limit, with

Brick-Wall Never-Exceed circuitry » Password protection available to lock out a

selectable control set » Key switch, active, and passive interlocks » Brown-out & overvoltage protection » Power supply overcurrent protection » Driver over-temperature protection circuit » Relay shorts output when current is

disabled » AC input and patented power supply

ﬁ ltering » 2 second turn-on delay — adjustable » 1.5 msec current ramp

OEM VERSION AVAILABLE

Once you have ﬁ nalized your work, the QCL circuitry is available in compact OEM versions.

APPLICATIONS

Due to their unique construction, QCLs operate with high power in the near-IR through terahertz ranges. These wavelengths are particularly suited to detection of molecules signiﬁ cant to humans.

Applications for the lower noise QCL driver include: remote detection of explosive materials, medical diagnosis using the breath, non-invasive glucose testing, emissions monitoring of the atmosphere or marine environments, and pharmaceutical process quality control. Additional applications include anesthesia and hospital air quality monitoring, leak detection, and remote imaging.

Covered by U.S. Patents 6,696,887; 6,867,644 and

7,176,755. Licensed from Battelle Memorial Institute

SAFETY

DEFINITIONS

CHASSIS GROUND Symbol

CAUTION: A condition that has the potential to cause damage to property or instrument.

WARNING: A condition that has the potential to cause bodily harm or death.

GENERAL

• Observe all Cautions and Warnings both in the User Guide and on the instrument.

• Use the QCL instrument as speciﬁ ed in this guide or the protection provided by this instrument may be impaired and the warranty will be voided.

• Use good laser safety practices when using the QCL instrument.

• Before proceeding, it is critical that you take precautions to prevent electrostatic discharge (ESD) damage to your laser.

• Locking the instrument with the key switch disables the output current. The key can only be removed when in the LOCK position.

FUSES

• Disconnect the power to the QCL instrument before changing the fuses.

• T o prevent damage to the QCL instrument when replacing fuses, locate and correct the problem that caused the fuse to blow before re-applying power.

• To avoid ﬁ re hazard, use only the speciﬁ ed fuse with the correct type number, voltage, and current ratings, and use only the recommended replacement parts.

CAUTIONS

The QCL instrument has no user-serviceable parts. Other than the fuses, the QCL instrument is not designed to be maintained by the user nor does it contain any parts that can be repaired by the user. All maintenance and repairs must be performed by Wavelength or the warranty will be void.

Use a soft cloth to remove dust from the QCL instrument. Do not expose the QCL instrument to any liquids, sprays, or solvents. To avoid electrical shock, unplug the power cord before cleaning the instrument.

Before connecting to the power source, make sure the correct cables and voltage for your area are set. The voltage selection is available on the back of the instrument. See the Quick Start Guide for instructions on changing the voltage.

POWER CORDS

• This equipment is grounded through the AC power cord grounding conductor.

• Use only the earth-grounded power cords that are recommended in this user guide.

• Route power cords and other cables so that they cannot be damaged.

• Position the QCL instrument in a location that makes it easy to quickly disconnect the power cord.

• To avoid ﬁ re hazard, use only the speciﬁ ed power cords with the correct grounding, voltage, and current ratings.

WARNINGS

Position the QCL instrument so that access to the Main Power On/Off switch on the back panel is easily accessed.

Do not use the QCL instrument if there is evidence of damage from shipping; damaged equipment can present signiﬁ cant safety hazards. If you suspect the QCL instrument is damaged, contact Wavelength technical support before attempting to operate the instrument.

To avoid electrical shock, use the recommended earth-grounded power cables and properly earthgrounded, 3-prong receptacles only. Failure to follow this precaution can result in severe injury.

To avoid injury, do not tell the engineers how to do their jobs. Let them muddle through until they decide to read the User Guide.

QUICK CONNECT GUIDE

INSTALL FUSE & SELECT VOLTAGE

Figure 1. Fuse Box and Voltage Selector

1. On the back panel, locate the Fuse Box and Voltage Selector receptacle. (See the Rear Panel diagram on page 10 for the location.)

2. Insert a small ﬂ athead screwdriver into the slot (1) at the top of the receptacle and twist to open faceplate. The red fuse drawer and fuses are located in the Ship Kit.

3. On the face of the fuse drawer are two voltage choices. Based on your country, select the proper fuses to install.

VOLTAGE FUSE PART NUMBER

100-120 V

220-240 V

1.25 A, 250 V, fast blow

0.63 A, 250 V, fast blow

Littelfuse 5 x 20 mm, Part #02351.25HXP

Littelfuse 5 x 20 mm, Part #0217.630MXP

WIRE A TEST LOAD

Use of a test load is recommended for setup of the QCL instrument. Use the Wavelength test loads listed on page 1, or when building your own test load, a 10  resistor with a 50 W power rating is recommended for the QCL500, QCL1000, and QCL1500. For the QCL2000, a 50 W 5  resistor is recommended.

• Install the test load by either connecting to the QCL SMA port or wiring the load to PIN 5 and PIN 9 on the QCL D-SUB as shown in Figure 3.

12345

6789

QCL

SMA

NOTE: The SMA case is electrically connected to the QCL chassis.

Figure 3. QCL Wiring Diagram

Pin 9 QCL +

or SMA Outer Ring

QCL D-SUB

QCL

CAUTION: It is imperative that the correct voltage is used. Serious damage can occur if the incorrect voltage is selected.

4. Insert the fuses as shown in Figure 2, with a short fuse at the contact end of the receptacle. Then, turn the drawer until the correct voltage label is at the top and replace it in the receptacle. Press ﬁ rmly to make sure the drawer is completely seated. It should be ﬂ ush with the receptacle.

Figure 2. Fuse Installation and Voltage Selector

5. Close the faceplate, again pressing ﬁ rmly until it is ﬂ ush. The correct voltage label is shown through the Voltage Window (2) on the faceplate.

QCL

Pin 5 QCL -

or SMA Center Pin

QCL Driver

Current Sink

-V

Figure 4. QCL Polarity Diagram

SETUP INTERLOCKS

ENABLE CURRENT

The Wavelength Interlock Replacement Kit includes a male D-SUB with the passive interlock pins shorted and a BNC terminator.

1. For the passive interlock, on the back panel, short PIN 1 and PIN 2 on the QCL D-SUB.

2. For the active interlock, on the back panel, insert a BNC terminator in the ACTIVE LOCK BNC port.

3. On the front panel, the key switch must be on UNLOCK to enable the current to the QCL.

TURN ON POWER

1. On the back panel, press the power switch to the |. The front panel power button light pulses slowly.

2. On the front panel, press the Power button. The button illuminates, the touchscreen activates, and the Control screen is active.

3. The front panel displays dashes instead of digits until the unit has ﬁ nished its power-up sequence (~10 seconds).

Press the ENABLE button. There is a standard 2-second delay before the button illuminates and the current ﬂ ows.

SHUTDOWN THE INSTRUMENT

If the Enable button is illuminated, current is still ﬂ owing to the test load. Before shutting down, the current needs to be turned off.

1. Press the Enable button. The button light will turn off and current to the QCL test load will stop.

2. On the front panel, press the Power button. The touchscreen will go black but the button light slowly pulses blue to indicate that the back Power button is still on. NOTE: Turning off only the front Power button puts the instrument in Standby mode.

3. On the back panel, press the power switch to O.

SET LIMITS

1. Press to access the Limit Screen.

2. On the Limit screen, press the blue Limit Current value and rotate the Adjustment knob to change to the desired value. The instrument will beep when set.

NOTE: The Max Supply V oltage and Cable Resistance values can be ignored for now.

ADJUST SETPOINT

1. Press to access the Control Screen.

2. Press the Setpoint current value and turn the Adjustment knob to change it. The instrument will beep when set.

QCL D-SUB

)

QCL

PIN DESCRIPTIONS

Pin 9 QCL +

or SMA Outer Ring

Figure 4. Female 9-Pin D-SUB

Table 1. QCL D-SUB Pin-Out

PIN DESCRIPTION

1, 2 Passive interlock pins (must be shorted to enable

current) 3 Chassis ground 4 Not used

5 * QCL- (negative)

6 Not used 7 Not used 8 Not used

9 * QCL+ (positive)

SHELL Chassis ground

* NOTE: Use Pins 5 and 9 for current to the QCL.

MONITOR D-SUB

QCL

Pin 5 QCL -

or SMA Center Pin

QCL Driver

Current Sink

-V

Figure 7. QCL Polarity Diagram

BNC PINS

GROUND

ACTIVE SIGNAL

Figure 8. BNC Pins

EXTERNAL MODULATION BNC TRANSFER FUNCTIONS

Figure 5. Male 9-Pin D-SUB

Table 2. Monitor D-SUB Pin-Out

PIN DESCRIPTION

1 Alignment LED (+5 V) can source 250 mA 2 Alignment LED ground 3 QCL current enabled indicator (+5 V TTL)

high = disabled

low, ground = enabled 4 QCL current enabled indicator ground 5 Not used 6 Analog setpoint monitor 7 Analog monitor ground 8 Analog output current monitor 9 Analog monitor ground

QCL SMA

+ (groun

The external modulation input, setpoint monitor, and analog current monitor transfer functions depend on the QCL instrument model and are all as follows:

QCL500-LAB: 0.1 A / V. QCL1000-LAB: 0.2 A / V. QCL1500-LAB: 0.3 A / V. QCL2000-LAB: 0.4 A / V.

The input range is always 0 – 5 V.

ACTIVE INTERLOCK BNC

Ground the center pin to the outer shell to override the interlock and allow the current to ﬂ ow to the QCL. If an external circuit won’t be used, a 50  or 75  terminator is acceptable.

TRIGGER BNC

See Remote Operation on page 21.

QCL- (negative

Figure 6. SMA Pin-Out

ELECTRICAL SPECIFICATIONS

DRIVER OUTPUT CURRENT MIN TYP MAX UNITS NOTES

Output Current 0.5, 1.0, 1.5, or 2.0 A RMS Noise Current 0.4 1.0 1.3 A RMS QCL1000 at 500 mA output, 100 kHz test bandwidth Noise Current Density 1 2 4 nA / Hz QCL1000 at 500 mA, 10  test load Stability, short and long term 5 10 15 ppm 25°C ambient Temperature Coefﬁ cient 5 10 18 ppm / °C

Internal Supply Voltage can be adjusted from the front panel.

Compliance Voltage Range 10 20 V

Slow Start Current Ramp (after Enabled)

Delayed Start 2 sec User adjustable

EXTERNAL MODULATION MIN TYP MAX UNITS NOTES

Modulation Bandwidth 2 3 MHz Sinewave Rise/Fall Time 250 / 200 nsec To full scale Slew Rate 30 V / sec Depth of Modulation 90 % At 500 kHz Input Impedance 1 k  External Modulation Input

Damage Threshold

1.5 msec

-10 to +10 V BNC Connector

NOTE: With this current source, the voltage developed across the load (laser) is not driven by the controller, but by Ohm’s Law and the resistance of the load (laser).

To setpoint

MONITORS AND OUTPUTS VALUE UNIT NOTES

Setpoint Resolution 16 bits 5V = fullscale output Display Accuracy Measurement

Resolution Accuracy, Current Output

Monitor vs. Actual Current (display or analog output)

Accuracy, Current Setpoint vs. Actual Current

Accuracy , Analog Setpoint

Monitor

Current Setpoint Monitor is a reference signal only, and may deviate from the actual setpoint by up to 5% when the setpoint is greater

than 10% of full scale.

24 Bits

0.2 % > 5% of full scale

0.5 % < 5% of full scale

0.2 % Internal setpoint

0.2 % External modulation 5 % >10% of full scale

25 % <10% of full scale

CONTINUED ON FOLLOWING PAGE

POWER SUPPLY REQUIREMENTS

AC Power Supply and Line Frequency

100-120 / 220-240 VAC, 2 A, 50-60 Hz

VALUE NOTES

Switch selectable: 100-120 V and 220-240 V,

appropriate power cord supplied Fuse for 220-240 V 0.63 A, 250 V, fast blow 5 x 20 mm, Part #0217.630MXP, Littelfuse Fuse for 100-120 V 1.25 A, 250 V, fast blow 5 x 20 mm, Part #02351.25HXP, Littelfuse Power Consumption 9.8 Watts at idle, no output to QCL load

GENERAL SPECIFICATIONS VALUE NOTES

Warm-up Time 1 Hour Remote Interface USB, Ethernet Warranty One (1) Year Safety Tested To IEC 61000-3-2

IEC 61000-3-3 IEC 61000-4-2 IEC 61000-4-3 IEC 61000-4-4 IEC 61000-4-5 IEC 61000-4-6 IEC 61000-4-8

IEC 61010-1

European Council Directive 2004/108/EC & European Council Directive 2006/95/EC

ABSOLUTE MAXIMUM

RATINGS

Case Operating Temperature Range

VALUE UNIT NOTES

-40 to 50 °C

Humidity 80 % Relative humidity at 30°C (non-condensing) Weight 12 (~5.4) lbs (kg)

Size

3.47 x 8.86 x 17.72 (89 x 226 x 450)

inches (mm)

OPERATING INSTRUCTIONS (STAND-ALONE)

WHAT’S IN THE BOX

• QCL Instrument

• Power Cable, type appropriate for ﬁ nal location

• Red fuse tray

• T wo 0.63 A fuses and two 1.25 A fuses for fuse box on the back panel

• USB Flash Drive, includes all necessary software, instrument documentation, and additional storage space

• Keys for the key switch

• Interlock Replacement Kit (interlocks for QCL D-SUB and Active Interlock BNC)

These instructions are for operating the QCL Laboratory Series instrument. Fuses are provided but not installed. After installing the fuses in the fuse box, be sure to install the fuse box so the correct voltage for your country is showing. We also recommend using a test load until you are familiar with operation of the instrument.

REQUIRED AND OPTIONAL EQUIPMENT

FOR SET UP

THEORY OF OPERATION

The QCL Series low noise drivers are designed expressly to drive quantum cascade lasers, and utilize patented1 circuitry to deliver ultra-low noise current and still maintain a wide modulation bandwidth.

The QCL 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.

As current is driven through the load, there is a voltage drop across the load proportional to the load resistance and current. 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 QCL driver includes features that help protect your laser, and also make the driver more versatile in a wide array of applications. These features are explained in detail in the Operating Instructions.

• The user-adjustable current limit prevents overdriving the laser even if the external modulation signal is above the maximum drive current for the laser.

• Over- and under-voltage protection circuits protect the driver and QCL if the power supply voltages fall outside of the acceptable operating range.

• Small, narrow headed ﬂ athead screwdriver (required)

• Test load (optional)

• Wavelength Interlock Replacement Kit with interlock overrides (optional)

COMPUTER REQUIREMENTS FOR REMOTE OPERATION ONLY (OPTIONAL)

Hardware

• 1 GHz or faster 32-bit (x86) OR 64-bit (x64) processor

• 1 GB RAM 32-bit or 2 GB RAM 64-bit

• 16 GB available hard disk space for 32-bit or 20 GB for 64-bit DirectX 9 graphics device with WDDM 1.0 or higher driver

Software

• Windows 8, 7 SP1, or Vista SP2 Operating System 4.5 .NET framework

ESD INFORMATION

Before proceeding, it is critical that you take precautions to prevent electrostatic discharge (ESD) damage to the load. ESD damage can result from improper handling of sensitive electronics, and is easily preventable with simple precautions.

• Over-temperature protection circuits safely shut down the output if the internal temperature of the QCL driver rises to an unsafe level. The fan turns on to manage the internal temperature.

• Output slow-start ramps the current to setpoint over

1.5 msec.

• A mechanical relay shorts the output connections when the output is disabled, and when the QCL driver is powered off.

Covered by U.S. Patents 6,696,887; 6,867,644 and

7,176,755. Licensed from Battelle Memorial Institute.

REAR PANEL

CAUTION: No user serviceable parts. Do not remove cover.

Covered by U.S. Patents:

6,696,887 6,867,644 7,176,755

SERIAL #

WARNING: Before powering on device, verify voltage setting is correct and proper fuses are installed.

CHASSIS

GND

QCL

Figure 9. Rear Panel

QCL

MONITORS

MOD

ACTIVE

LOCK

FUSE ~250V, 1.25AF (5 x 20mm)

100-120 VAC, 1.25 A, 50-60 Hz

ETHERNETUSB

TRIGGEREXT

FUSE ~250V, 0.63AF (5 x 20mm)

220-240 VAC, 0.63 A, 50-60 Hz

Table 3. Rear Panel Functions

NAME DESCRIPTION

1 Fan Vent Do not block air ﬂ ow. 2 Chassis Ground Physical connection to chassis and electrical earth ground. 3 QCL SMA SMA connector, alternate connection to QCL. 4 QCL D-SUB 9-Pin female D-SUB connector. 5 Monitors 9-Pin male D-SUB connector. 6 USB USB port, connection between instrument and a computer. 7 Ethernet Ethernet port, connection between instrument and a computer or network. 8 EXT MOD External Modulation: BNC connector, setpoint signal generator input. 9 Active Lock BNC connector, active interlock, tie center pin to GND to enable output.

10 Trigger

11 12 Power Switch AC power switch that powers the instrument.

13 Power Plug IEC AC line input.

Fuse Box and Voltage

Selector

BNC connector output, allows instrument to trigger external device for synchronizing measurement.

Removable fuse drawer allows user to switch between 115 V and 230 V. Fuses need to be installed prior to operation.

INSTALL FUSES AND SELECT PROPER VOLTAGE

Figure 10. Fuse Box and Voltage Selector

1. On the back panel, locate the Fuse Box and Voltage Selector receptacle. (See the Rear Panel diagram on page 10 for the location.)

2. Insert a small ﬂ athead screwdriver into the slot (1) at the top of the receptacle and twist to open faceplate. The red fuse drawer and fuses are located in the Ship Kit.

3. On the face of the fuse drawer are two voltage choices. Based on your country, select the proper fuses to install.

CONNECT POWER

Insert the female end of the IEC AC power cord into the Power receptacle on the back panel and then plug the male end into the power source.

WIRE A TEST LOAD

• Install the test load by either connecting to the QCL SMA port or wiring the load to PIN 5 and PIN 9 on the QCL D-SUB as shown in Figure 12.

12345

6789

QCL D-SUB

VOLTAGE FUSE PART NUMBER

100-120 V

220-240 V

1.25 A, 250 V, fast blow

0.63 A, 250 V, fast blow

Littelfuse 5 x 20 mm, Part #02351.25HXP

Littelfuse 5 x 20 mm, Part #0217.630MXP

CAUTION: It is imperative that the correct voltage is used. Serious damage can occur if the incorrect voltage is selected.

4. Insert the fuses as shown in Figure 11, with a short fuse at the contact end of the receptacle. Then, turn the drawer until the correct voltage label is at the top and replace it in the receptacle. Press ﬁ rmly to make sure the drawer is completely seated. It should be ﬂ ush with the receptacle.

QCL SMA

NOTE: The SMA case is electrically connected to the QCL chassis.

QCL

Figure 12. QCL Wiring Diagram

Pin 9 QCL +

or SMA Outer Ring

Test Load

Pin 5 QCL -

or SMA Center Pin

QCL Driver

Current Sink

-V

Figure 13. Test Load Polarity Diagram

Figure 11. Fuse Installation and Voltage Selector

5. Close the faceplate, again pressing ﬁ rmly until it is ﬂ ush. The correct voltage label is shown through the Voltage Window (2) on the faceplate.

SET UP INTERLOCKS

TEXT AND ICON COLOR KEY

The Wavelength Interlock Replacement Kit includes a male D-SUB with the passive interlock pins shorted and a BNC terminator.

1. For the passive interlock, on the back panel, short PIN 1 and PIN 2 on the QCL D-SUB.

2. For the active interlock, on the back panel, insert a BNC terminator in the ACTIVE LOCK BNC port.

3. On the front panel, the key switch must be on UNLOCK to enable the current to the QCL.

NOTE: To disable operation, turn the key switch to the LOCKED position. The key can only be removed when in the locked position.

FRONT PANEL

TEXT

Text indicates current state.

White, Green Uneditable ﬁ eld, for information only. Blue Editable ﬁ eld, touch to select or toggle ﬁ eld

(text highlights and changes color), adjust using either the touchscreen or adjustment knob. Instrument beeps and text returns to blue when values are set. Touch again to cancel selection.

ICONS

Icon color indicates current state.

Blue Screen is active. Grey Screen is inactive, touch icon to access that screen.

QCL1000 LAB

ENABLE

POWER

DATA

Figure 14. Front Panel Table 4. Table 5. Front Panel Functions

NAME DESCRIPTION

1 Power Button 2 Adjustment Knob Turn to adjust the numeric values. Instrument beeps when values are set.

3 Enable Button Allows instrument to deliver current to the QCL. Glows blue when current is enabled. 4 Keylock Switch

5 Data Port

Powers the application electronics. Glows blue when application electronics power is on and unit is operational, slow pulses blue when on Standby and only the back panel power switch is on.

UNLOCK allows laser output current to ﬂ ow, LOCK disables laser output current. NOTE: The key can be removed only in LOCK position.

USB ﬂ ash drive, used to update the ﬁ rmware or save data. This is not used for remote USB control of the instrument.

TURN ON QCL INSTRUMENT

1. Press the Power switch on the back panel to |. The front

panel power button light slowly pulses.

2. Press the Power button on the front panel, the button

illuminates, touchscreen is activated, and the Control screen is active.

NOTE: Turning off front Power button powers down the application electronics and puts the unit into standby mode. Turning off rear Power switch powers down all electronics and settings return to factory default.

3. The front panel displays dashes instead of digits until the

unit has ﬁ nished its power-up sequence (~10 seconds).

SET LIMITS

1. Press to access the Limit Screen.

ADJUST THE SETPOINT

1. Press to access the Control Screen.

2. Press the Setpoint value and turn the Adjustment knob until the desired operating current is displayed.

2. Press Limit Current, Maximum Supply Voltage, and/or Cable Resistance values and rotate the Adjustment knob to change each value. The instrument will beep when set.

Figure 15. Limit Screen

NOTES:

• The Limit Current should not exceed the damage current threshold of your QCL.

• The Maximum Internal Supply Voltage can be lowered to minimize internal instrument temperature or to act as a compliance voltage clamp on the QCL output current. See Additional Technical Notes on page 25 for optimization instructions.

• The Cable Resistance range is 0 – 1 . QCL Voltage displays the voltage at the QCL DSUB or

SMA terminals. To account for voltage loss across the cable to the QCL, you can enter a non-zero value for Cable Resistance.

The QCL Voltage will now display as:

Voltage Displayed = Voltage@Pins - (Cable Resistance x Operating Current)

• The minimum limit current is about 8% of full scale.

Figure 16. Control Screen

NOTE: The Control screen is on by default when the instrument is turned on. The Mode is Constant Current by default and cannot be changed.

DISPLAY EXISTING CURRENT AND VOLTAGE VALUES

Press to access the Monitor Screen.

Values on this screen cannot be changed and are for information only.

Figure 17. Monitor Screen

ENABLE THE QCL INSTRUMENT

Press the Enable button on the front panel. The button will glow blue only when current is delivered to the load. There is a standard 2-second delay before the button illuminates and current ﬂ ows.

VI SCAN

1. On the Control screen, press to access the VI scan screen.

2. Press the Current Start value to select the current at which to start the scan. Turn the Adjustment knob to change it.

NOTES:

• The step interval time is approximate. In the scan ﬁ les, time intervals are slightly more than the step interval indicated on the instrument. Each interval builds on the previous one.

• Should the Step Size interval not ﬁ nish at the Stop Current, the reading is still taken and recorded. For example, if the Start Current is 250 mA and the Stop Current is 1.04 A with a Current Step of 250 mA, a reading is taken at 1000 mA (1 A) and 1040 mA (1. 04A) but not at 1250 mA (1.25 A).

• After a VI scan is completed, the output is disabled and the setpoint is zeroed.

SAVE OR RECALL SETTINGS

Press to access the Save/Recall Screen.

Figure 18. Scan Screen

3. Press the Current Stop value to select the current at which to stop the scan.

4. Press the Step Size value to select the current interval at which to take a measurement. The maximum interval is 10% of full scale. Minimum step is 1% of full scale.

5. Press the Time Interval value to select the amount of time to allow the current to settle. For the best data accuracy, use a Time Interval of 2 seconds or more. The minimum time interval is 0.1 seconds.

6. Insert the USB ﬂ ash drive in the USB slot on the front panel.

7. Press the green Run button to start the scan. When ﬁ nished, data is saved to the USB ﬂ ash drive with the ﬁ lename viscanxx.txt, where xx starts at 00 and increments.

8. To stop mid-scan, press the red Stop button to abort the scan. Any data collected during the aborted scan is saved to the USB ﬂ ash drive.

Under Save Settings to, press the blue text to toggle through the Proﬁ le options, select one, and then press the Save icon.

The following variables are saved:

OPERATION SETTINGS VI SCAN SETTINGS

Setpoint VI Start Current Current Limit VI Stop Current Max Supply Voltage VI Step Size Cable Resistance VI Time Interval Display Brightness Beeper Status

Figure 19. Save / Recall Screen

Under Recall Settings from, press the blue text to toggle through the saved Proﬁ le options, and then press the Recall icon to recall the saved settings. Select Factory to restore the settings to the factory defaults.

SETTINGS SCREEN

Press to access the Settings Screen

Move the slider bar on the touchscreen to change the display brightness. Press the blue text to toggle the Beeper on-off setting.

EXTERNAL MODULATION (EXT MOD) BNC

This is the external modulation input. The voltage input on this BNC sums with the DC value on the screen. The input impedance is 1 k . To calculate the external modulation signal voltage, see the next section for the transfer function, and use the following equation:

EXT_MOD

= I

CAUTION: Connect the oscilloscope across the test load only — never connect the oscilloscope across a quantum cascade laser.

If the external modulation input causes the driver to reach the current limit, the output signal will be clamped at the limit level but will not switch off.

The bandwidth of the Current Monitor is lower than the bandwidth of the output. To monitor the actual output waveform at high frequencies, connect an oscilloscope across the output pin on the MONITOR D-SUB, Pin 8 (positive), and Pin 9 (ground) while using the resistor test load.

/ Transfer Function

SETPOINT

Figure 20. Settings Screen

LOCK OR UNLOCK SETTINGS (OPTIONAL)

Settings are not locked.

This is the default. Critical values set with the Adjustment knob can be locked. Press to lock the settings.

Settings are locked.

Press to unlock the settings.

Settings are locked and password protected.

Locked settings that are password protected can only be locked and unlocked using a remote computer.

EXTERNAL MODULATION BNC TRANSFER FUNCTIONS

The external modulation transfer function depends on the QCL instrument model and is as follows:

QCL500-LAB: 0.1 A / V. QCL1000-LAB: 0.2 A / V. QCL1500-LAB: 0.3 A / V. QCL2000-LAB: 0.4 A / V.

The input range is always 0 – 5 V.

ADDITIONAL CAPABILITIES

ANALOG CURRENT MONITOR

This signal is the sum of the DC setpoint as shown on the screen and the external modulation input.

To monitor the analog current level:

1. Connect the Analog output Current Monitor (PIN 8) on the

MONITOR D-SUB to an oscilloscope.

2. Connect an Analog Monitor Ground (PIN 7 or PIN 9) to

oscilloscope ground.

SETPOINT CURRENT MONITOR

This is a reference only and can be off by as much as 5% when setpoint is >10% of full scale.

To monitor the setpoint current:

1. Measure the voltage on the Analog Setpoint Monitor (PIN 6).

2. Ground for that measurement is the Analog Monitor Ground

(PIN 7 or PIN 9).

The setpoint monitor and analog current monitor transfer functions depend on the QCL instrument model and are all as follows:

QCL500-LAB: 0.1 A / V. QCL1000-LAB: 0.2 A / V. QCL1500-LAB: 0.3 A / V. QCL2000-LAB: 0.4 A / V.

The input range is always 0 – 5 V.

ALIGNMENT LED DRIVE

+5 V, up to 250 mA sourced.

To drive an alignment LED, on the MONITOR D-SUB

1. Connect an LED to the Alignment LED +5V (PIN 1).

2. Ground the LED at the Alignment LED Ground (PIN 2).

ENABLE STATUS INDICATOR

This is a +5 V TTL indicator. If current to the QCL output is enabled, the voltage between PIN 3 and PIN 4 on the MONITORS D-SUB will be low. It will be high if current is disabled.

OPERATING INSTRUCTIONS (REMOTE)

http://www.teamwavelength.com/support/software.php.

http://www.teamwavelength.com/support/software.php

INSTALL THE LAB QUICKCONNECT APPLICATION SOFTWARE

The QuickConnect software is necessary for remote operation of the instrument. The software can be installed on the remote computer from either the USB ﬂ ash drive included with your instrument or from the Wavelength website.

• On the USB ﬂ ash drive, the software is located in the \ setup folder.

• On the Wavelength website, the link to the software is located at

http://www.teamwavelength.com/support/software.php.

NOTE: .NET 4.5 software is required to run the application. If it is not currently installed on the remote computer, it will be installed automatically when you insert the ﬂ ash drive.

TO INSTALL THE SOFTWARE,

1. From the USB ﬂ ash drive or the Wavelength website and in the ﬁ le dialog box, select the software version that corresponds to your computer system type, either 32-bit or 64-bit. NOTE: If the incorrect system type is selected, an error message will appear and the software will not install.

2. Click the computer system’s setupxx.exe ﬁ le, where “xx” refers to the system type. The Preparing to Install dialog box opens and the software automatically extracts the ﬁ le.

3. On the Welcome window, click Next.

4. On the Destination Folder window, click Next to accept the default Wavelength folder or Change to select a different folder. When the new folder has been selected, click Next.

5. On the Ready to Install window , review the settings, click Install.

6. On the Windows Security window, click Install.

7. On the Completed window, select the Launch the program checkbox to open the application and then click Finish.

The ﬁ le is found at:

http://www.teamwavelength.com/support/software.php

3. Extract the ﬁ le on the ﬂ ash drive. It should contain the following ﬁ les:

\INSTALL.INI \QCLxx\ABL.IMG \QCLxx\APP.IMG \QCLxx\INSTALL.INI

NOTE: “QCLxx” is replaced with the instrument model number, such as QCL2000.

4. Insert the ﬂ ash drive into the front DATA port on the instrument. The update automatically begins installation.

5. At the Apply the ﬁ rmware screen, click Yes. The ﬁ rmware update installs.

6. Once the update is complete, click OK and reboot the instrument by turning off the front and rear panel power buttons and turning them back on again.

7. (Optional) To conﬁ rm the latest version is installed on the instrument, after the instrument is on, swipe the touchscreen to show the system information screen. The new version number is displayed.

CONNECT AN INSTRUMENT TO A REMOTE COMPUTER

1. Connect the QCL instrument to a power source. See the Stand Alone operation instructions on page 11 for more information.

2. Connect the instrument to the computer using a USB or Ethernet cable. If connecting more than one instrument, a USB or Ethernet hub may be required.

3. Turn on the rear panel Power switch. The front panel Power button pulses blue.

4. Turn on the front panel Power button. The button glows steadily blue and the touchscreen activates.

UPDATE THE INSTRUMENT FIRMWARE

Updates to the instrument ﬁ rmware are available on the Wavelength website.

1. Turn the instrument completely off at both the front and rear panels, and then turn it completely on again.

2. On the Wavelength website, download the ZIP ﬁ le that is speciﬁ c to your QCL Laboratory Series model and save the update ﬁ le to a ﬂ ash drive.

ACCESS THE INSTRUMENT ON A REMOTE COMPUTER

1. On the computer and from the Start Menu, click All

Programs, then click Wavelength Electronics, and then LAB QuickConnect. The LAB QuickConnect Application

window opens.

2. In the LAB QuickConnect Application window, click Open Instrument.

3. In the Choose Instrument To Open window, select the instrument to connect to and click Open.

Figure 20. Include USB Devices window

NOTES:

• The Include USB Devices checkbox is selected by default and any powered instruments currently connected to the computer via a USB cable appear in the list.

• If you are unsure which instrument to select, on the instrument, swipe the touchscreen ﬁ rmly from left to right. The instrument details screen, including the serial number, appears.

• Instruments that are connected to subnets can be added to the list.

1. Select the Include Network Devices checkbox, add

the IP address or host name of the subnet, and then click Add Host.

2. Click Refresh. Any instruments connected to that

subnet appear in the list.

Figure 22. Remote Computer Control screen

Figure 23. Instrument touchscreen when controlled remotely

CHANGE THE TURN-ON DELA Y

The default delay between the time the current to the laser is enabled and the current actually ﬂ ows is 2 seconds. This turn-on delay can be set to a minimum of 0 seconds and a maximum of 5 seconds.

1. On the Operation Tab, click on the blue text below Turn- On Delay.

2. Change the value and tab to a new editable ﬁ eld to save the change.

Figure 21. Include Network Devices window

3. On the Instrument Operation tab, in the lower left, click Seize. Control of the instrument will transfer from the

instrument to the computer and a screen of all editable ﬁ elds appears. The computer screen is editable and the instrument screen is not.

NOTE: One instrument can be controlled remotely at a time.

CONTEXTUAL HELP

At any time, contextual Help Information appears on the right side of the window when the pointer is placed over a button or screen element. Technical Support information, such as the instrument serial number and Wavelength contact information is available when the pointer is placed over the grey frame surrounding the window.

SUPER USER VS. NORMAL USER PERMISSIONS

There are two levels of permissions when modifying the instrument controls, Super User and Normal User.

Super User: The Super User has the ability to modify any remote operation and to assign permissions for Normal Users. A password is required to access Super User features. Upon ﬁ rst sign in, the password entered is the new Super User password and is required for subsequent sign ins.

Normal User: The Normal User is primarily used for Local operation. The Super User can restrict access to speciﬁ c inputs on the instrument.

ACCESS SUPER USER MODE

When control of the instrument is ﬁ rst seized, it is in Normal User mode.

1. On the Instrument Operation tab and at the bottom, click Super User.

2. Type the password in the text box and click OK. Select the Show Password checkbox to type the password as text.

NOTE: Upon ﬁ rst sign in, the password typed becomes the password for subsequent sign ins.

EDIT INSTRUMENT PROFILES

Proﬁ les can be edited in Super User mode or when Normal Users are not restricted from saving proﬁ les.

1. In the Proﬁ le Editor Window and in the Available

Proﬁ les menu, select a proﬁ le. The factory default proﬁ le, Proﬁ le 0: Factory Default, cannot be changed.

2. Type values in the Proﬁ le Data boxes.

3. (Optional) In the Description Line 1 and 2, type a description of the proﬁ le. This text replaces the Save- Recall Proﬁ le text on the instrument. A maximum of 14 characters are saved.

4. (Optional) To grant Normal Users read-write permissions, select the appropriate checkbox.

• Local User Can Save/Modify This Proﬁ le: Allows any user to change any preset proﬁ le value on the instrument.

• Normal User Can Recall: Allows any user to recall preset proﬁ les. This is selected by default.

5. Click Apply to Instrument and/or Save.

• Click Apply to Instrument to change the values on the instrument but not save the changes to the Proﬁ le.

• Click Save to save changes to the Proﬁ le but not change the values on the instrument.

• Click Apply to Instrument and then Save, to apply changes to the instrument and then save the changes to the Proﬁ le.

Figure 24. Enter Password window

6. .

Figure 25. QCL-LAB Proﬁ le Editor window

EDIT ADV ANCED OPTIONS

CHANGE SUPER USER PASSWORD

Advanced Options can only be edited in Super User mode.

Figure 26. Advanced Options window

CHANGE PERMISSIONS

Permissions can only be modiﬁ ed in Super User mode and apply only to Normal User mode.

1. Under Permissions, select Apply Restrictions To Instrument.

NOTE: To apply the restriction changes to the instrument, this checkbox must be selected when the selections are saved.

2. Select the appropriate checkbox to restrict access to those values. Click All to select all the checkboxes or None to clear them. All restrictions apply to Normal Users when the instrument is in Normal User mode or when operated in local mode.

3. Click Save.

NOTES:

• Restrictions checkboxes can be selected and saved without applying the changes to the instrument.

• To apply the local Save Proﬁ le and Recall Proﬁ le options to the instrument, the local user Save/Modify and Recall checkboxes on the Proﬁ le Editor must also be checked, as well as the Apply Restrictions checkbox on the Advanced Options dialog box.

1. On the Instrument Operation tab, click Super User.

2. Type the password in the text box and click OK. Select the Show Password checkbox to type the password as text.

3. Under Permissions, click Change Super User Password.

4. Type a new password and then click OK.

CHANGE NETWORK CONFIGURATION SETTINGS

Network conﬁ gurations can only be changed in Super User mode.

1. Under Network Conﬁ gurations, click Edit Network Conﬁ guration.

2. Type the new information into the text boxes and click Save.

POWER INSTRUMENT ON OR OFF

The front panel can be turned on or off using a remote computer. When the front panel Power button is turned on, the button displays a blue circle and the screen displays all editable values on the instrument. When it is turned off, the screen is black and only the Power button, without the blue circle, is available. This is equivalent to pressing the front panel Power button.

• On the Instrument Operation tab, click the Power button.

Figure 27. Power button on Figure 28. Power button off

CHANGE VALUES ON INSTRUMENT

RUN A VI SCAN

Blue and yellow text denotes editable values, green and white text is not. Press TAB to move to the next editable ﬁ eld.

1. On the Instrument Operation tab, click the blue text to edit. The text turns yellow when in editing mode.

2. Tab to or click on blue text to edit the value.

NOTE: Tabbing to a new editable text ﬁ eld saves changes made to the previous value. Manually moving the cursor to a new ﬁ eld does not save the change, which reverts to the last saved value.

1. On the Instrument Operation tab, click the green arrow. A Specify Data File window opens.

2. Navigate to the location to save the scan data, name the ﬁ le as desired, and click Save.

3. A new window opens showing the scan in progress.

• To stop the scan, click Stop Scan. Data collected up to the point the scan was stopped is recorded in the data ﬁ le.

4. To dismiss the scan window, click Close.

Figure 29. Text color indicates ability to edit

ENABLE OR DISABLE CURRENT TO THE LASER

Current to the laser can be enabled or disabled using a remote computer. When the current is enabled, the Enable button glows blue.

• On the Instrument Operation tab, click the Enable button.

Figure 30. Enable button on Figure 31. Enable button off

Figure 32. VI Scan screen

END REMOTE OPERATION

Returning the instrument to local operation is accomplished one of two ways:

• On the Instrument Operations tab and at the bottom, click Close Instrument.

• On the instrument, tap Press For Local.

USE THE TRIGGER SIGNAL

A trigger signal is provided so that external measurement equipment can be synchronized with laser current. Exactly 10 msec after a remote change in setpoint, a 20 sec positive going pulse appears on the Trigger BNC plug.

To use the Trigger, connect a BNC cable to the TRIGGER BNC output.

TROUBLESHOOTING

Table 5. Troubleshooting

PROBLEM POTENTIAL CAUSES SOLUTIONS

The button has been pushed on and

Front panel Power button does not turn on

The Enable button does not turn on

The instrument is on but the front panel display is blank

The date and time on my VI scan ﬁ le are wrong

The VI scan ﬁ les are not in the order that they were created

Unable to create new VI scans

I can’t ﬁ nd my VI scan ﬁ les VI scan ﬁ les are named sequentially.

The fan keeps coming on

off within 3 seconds.

The rear panel switch is off. The button has been turned on and off

within 2 seconds.

The QCL D-SUB interlock or Active Interlock connections are open, or the keyswitch is in the LOCKED position

The instrument experienced an internal fault. (See Error Messages on page 24.)

The instrument heatsink temperature has exceeded 70ºC.

The front panel Power button is not on.

The instrument experienced an internal fault. (See Error Messages on page 24.)

The internal temperature has reached an unsafe level.

The front panel Power button is pulsing on and off in standby mode.

Some ﬁ les may have been deleted off of the USB ﬂ ash drive.

The interlocks may not be satisﬁ ed.

There are too many ﬁ les on the USB ﬂ ash drive.

The internal temperature is being regulated.

The front panel Power button has a 3 second delay between when it is turned off and on in rapid succession. This is a safety mechanism to ensure there is no damage to either the QCL instrument or the attached load.

Turn the rear panel switch to the on or | position.

The button cannot be pressed faster than every 2 seconds.

• Make sure PIN 1 and PIN 2 on the QCL D-SUB are shorted.

• The “Active Lock” BNC connector may be open. Install a BNC shorting plug.

• Rotate the key to the UNLOCKED position.

The instrument will remain disabled until manually powered off and then on using the rear panel power switch.

Allow the instrument to cool down and then press the front panel power button.

Press the Power button on the front panel to enable the display.

Switch the back panel power button off and then on again, and turn the front panel power button on.

Allow the instrument to cool down and then switch the back panel power button off and then on again, and turn the front panel power button on.

Press the Power button on the front panel to enable the display.

The QCL instrument does not have a realtime clock. When a VI scan ﬁ le is created, the date and time stamp are randomly chosen.

When ﬁ les are deleted off of the USB ﬂ ash drive and new ﬁ les are saved to it, the new ﬁ les are given sequentially the names of the deleted ﬁ les.

Turn the keyswitch to UNLOCKED, or install the ACTIVE LOCK BNC and passive interlocks.

Delete ﬁ les from the USB ﬂ ash If ﬁ les have been deleted from the ﬂ ash drive,

any new ﬁ les added are named sequentially and have the names of the deleted ﬁ les.

To reduce internal heat generation, choose a lower supply voltage. The instrument will shut down if the internal temperature gets too hot.

drive.

PROBLEM POTENTIAL CAUSES SOLUTIONS

http://www.teamwavelength.com/downloads/ notes/an-ld08.pdf

http://www.teamwavelength.com/downloads/ notes/an-ld09.pdf

There may be ground loops in the system; some system components

Noise current is higher than expected.

The output switched off unexpectedly

20 kHz noise is in the output current QCL driver is operating in current limit.

If I run my QCL at about 5% of maximum output current, the transfer function becomes non-linear and I see distortion in my output current waveform.

My instrument doesn’t show up in the list. (Remote Only)

Actual current does not match the setpoint.

may be higher noise than expected; cabling and shielding may be inadequate.

The instrument detected an internal error

(See Error Messages on page 24.) The internal temperature has

exceeded 70ºC.

QCL driver resolution is too low.

Your instrument may not be turned on.

Your instrument may not be plugged in to the computer.

Your instrument may be on a different sub-net.

The setpoint exceeds the limit current setting.

The QCL is compliance voltage limited.

Refer to Wavelength Electronics Application Note AN-LD08: “Manage Grounding to Minimize Noise with the QCL Drivers”:

http://www.teamwavelength.com/downloads/ notes/an-ld08.pdf

Also reference AN-LD09: “Troubleshooting Low Noise Systems”:

http://www.teamwavelength.com/downloads/ notes/an-ld09.pdf

Switch the back panel power button off and then on again, and turn the front panel power button on.

Allow the instrument to cool down and then press the front panel power button.

If safe for the quantum cascade laser, increase the output current limit setting. When actively operating in current limit, the safety circuits add noise to the output.

Select a QCL driver with a much lower maximum output current. For example, to run 50 mA, request a QCL125 (125 mA maximum output).

Power up the instrument and click Refresh on the Choose Instrument window.

Check that either a USB or Ethernet cable is tightly connected to the instrument and to the computer.

Add the sub-net to the Choose Instrument window and then click Refresh.

If the limit current can be increased without damage to the QCL, increase the limit current setting.

Increase the Max Supply Voltage slightly to see if actual current increases. Follow the instructions on page 25 to optimally set the Max Supply Voltage.

Table 6. Error Messages

To clear error text, ﬁ x the cause then press any icon or the Enable button.

ERROR POTENTIAL CAUSES SOLUTION

The USB ﬂ ash drive is missing or not accessible. Please make sure that a USB ﬂ ash drive is inserted into the front panel.

The USB ﬂ ash drive was removed. The scan has been aborted.

Output current is disabled. The keyswitch is in the locked position.

Output current disabled. Pins 1 & 2 on the QCL D-SUB are not tied.

Output current disabled. The Active Interlock is not shorted.

The internal temperature limit of the instrument has been exceeded. Output current has been disabled to protect the laser.

The VI scan was canceled by the user. Scan was canceled because output

current is disabled. An open circuit was detected at the

load. Please verify the load and load connections.

A short circuit was detected at the load terminals. Please verify the load and load connections.

An internal error occurred while reading data from hardware. Please contact the factory for further assistance.

A timeout occurred waiting for output. Make sure the load is connected and interlocks are satisﬁ ed.

An internal error was detected. Please contact the factory for further assistance.

A fault in the internal +5V supply was detected. Please contact the factory.

A fault in the internal +15V supply was detected. Please contact the factory.

A fault in the internal -15V supply was detected. Please contact the factory.

A timeout occurred waiting for the internal load power supply to stabilize. Please contact the factory.

A problem has been detected in the instrument power supply. Please contact the factory for further assistance.

A current surge has been detected in the instrument. Output has been disabled to protect the laser.

To run a local VI scan, a USB ﬂ ash drive must be in place.

The keyswitch is horizontal or in the locked position.

The passive interlock is not shorted. Short Pin 1 and Pin 2 on the QCL D-SUB.

The active interlock is not grounded.

The ambient air temperature is too high for the instrument.

The Stop button was pressed during the scan.

The Enable button was pressed during a scan, cutting current to the load.

The instrument cannot drive current through the load.

The instrument is detecting that there is no resistance where the load should be.

Insert a USB ﬂ ash drive in the data port on the front panel.

Turn the keyswitch to the vertical or unlocked position.

Ground the center pin of the Active Lock BNC.

Reduce the ambient air temperature to 50ºC or less.

Make sure the QCL SMA or Pins 5 & 9 of the QCL D-SUB are connected.

Contact Wavelength technical support for further assistance.

Contact W further assistance.

avelength technical support for

ADDITIONAL TECHNICAL NOTES

This section includes useful technical information on these topics:

• Reduce internal temperature or provide compliance voltage limit

• Use Passive and Active interlocks

• Soft-clamp current limit

• Square wave response

• Remove the bail and feet from an instrument

REDUCE INTERNAL TEMPERATURE OR PROVIDE COMPLIANCE VOLTAGE LIMIT

At full current, the Maximum Compliance Voltage available to the QCL is about 7.5 V below the maximum supply voltage. This 7.5 V estimate decreases as operating current decreases. To determine the best internal supply voltage for your application, follow these steps:

1. Wire your QCL to the instrument and adjust the current limit on the Limit screen and setpoint on the Control screen for your application.

2. Press the Enable button to enable the output current. The actual current displayed should match the setpoint.

3. On the Limit screen, select the blue MAX Supply Voltage value and, using the Adjustment knob, adjust it down slowly until the actual current starts to decrease. The QCL current is now limited by the compliance voltage of the instrument.

4. Using the Adjustment knob, now increase the MAX Supply Voltage value until the current is no longer below the setpoint. This is the optimal maximum supply voltage for your setup.

5. On the Monitor screen, observe the QCL Voltage. This is the voltage across the QCL at this operating current and is the effective voltage limit to the QCL for your setup.

NOTE: If you reach 18 V on the MAX Supply Voltage input and the current is still not compliance voltage limited, the instrument is operating at its lowest voltage and the voltage limit cannot be reduced further.

SOFT-CLAMP CURRENT LIMIT

The QCL driver employs a soft-clamping current limit that begins to act at a current lower than the calculated absolute current limit.

The Limit Current is the absolute current limit, which is the current that will not be exceeded under any circumstance.

Because of the soft-clamp circuit, the actual current where the limit circuit begins to act is 20% below the absolute current limit.

If the output current is between this point and the Absolute Current Limit, the output response to the analog input setpoint is nonlinear. The result is that the drive current will asymptotically approach the absolute current limit, and will never exceed it even if the external modulation setpoint voltage far exceeds the current limit.

Figure 33 illustrates the behavior of the soft-clamp current limit. In this case the analog input voltage setpoint signal is a triangle wave, with the amplitude set so that the driver will attempt to overdrive the current limit.

Figure 33. Soft Clamping Current Limit Behavior

USE P ASSIVE AND ACTIVE INTERLOCKS

The passive interlock is designed to trigger if Pins 1 and 2 on the QCL D-SUB are not shorted. Use this interlock with doors and enclosures that trigger an open circuit when opened.

The active interlock (ACTIVE LOCK BNC) can be used with a temperature controller or other active system component to disable the current output if the QCL exceeds an acceptable temperature operating range.

SQUARE WAVE RESPONSE

Figure 34 and Figure 35 illustrate the modulation response of the QCL1500 driven at 1.15 A into a 10  test load.

Figure 34. 10 kHz Output Plot

QCL1500 at 1.15 A with 10 Ω Test Load

Figure 35. 600 kHz Output Plot

QCL1500 at 1.15 A with 10 Ω Test Load

REMOVE THE BAIL AND FEET FROM AN INSTRUMENT

To make sure there is the proper clearance between stacked instruments when rack mounting, the feet and bail must be removed.

On the underside of the instrument, using a Phillips head screwdriver, unscrew the four rubber feet.

MECHANICAL SPECIFICATIONS

3.47

[88.14]

16.35

[415]

8.860

[225.0]

0.66

[16.8]

3.92

[99.6]

6.10

[154.9]

8.860

[225.0]

3.47

[88.14]

8.49

[215.6]

17.72 [450]

16.35

[415]

0.72

[3.89]

Dimensions are in inches [mm].

Tolerance is ±5%.

CE DECLARATION OF CONFORMITY

CONFORMING PRODUCTS

MODEL NUMBER PRODUCT

QCL500-LAB 500 mA QCL Driver Laboratory Instrument QCL1000-LAB 1000 mA QCL Driver Laboratory Instrument QCL1500-LAB 1500 mA QCL Driver Laboratory Instrument QCL2000-LAB 2000 mA QCL Driver Laboratory Instrument

DECLARATION

The undersigned hereby declares, on behalf of Wavelength Electronics, Inc. (Wavelength) of Bozeman, Montana, that the products listed in the table above, to which this Declaration applies, are in conformity with the provisions of:

APPLICABLE REGULATIONS

• European Council Directive 2004/108/EC (December 15, 2004) on Electromagnetic Compatibility, tested to: » IEC 61000-3-2 and IEC 61000-3-3

» IEC 61000-4-2, IEC 61000-4-3, IEC 61000-4-4, IEC 61000-4-5, IEC 61000-4-6, and IEC 61000-4-8

• European Council Directive 2006/95/EC (December 12, 2006) on Low-Voltage Equipment Safety, tested to: » IEC 61010-1

• European Council Directive 2011/65/EU (June 8, 2011) on Restriction of the use of certain hazardous substances in

electrical and electronic equipment (RoHS)

TECHNICAL FILE

The Technical Construction Files for the listed products, as required by this Declaration, are maintained at Wavelength corporate headquarters: 51 Evergreen Drive, Bozeman, Montana.

18-Nov-14

Mary Johnson, CEO Date

WARRANTY & CERTIFICATION

CERTIFICATION Wavelength Electronics, Inc. (Wavelength) certiﬁ es that this product

met its published speciﬁ cations at the time of shipment. Wavelength further certiﬁ es 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 is void if label is removed from back panel.

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.

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 signiﬁ cantly 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, deﬁ brillators, 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.

LIMITATIONS OF WARRANTY The warranty shall not apply to defects resulting from improper use or

misuse of the product or operation outside published speciﬁ cations. Warranty for the QCL instrument is invalid if the instrument cover has been removed for any reason. No other warranty is expressed or implied. Wavelength speciﬁ cally disclaims the implied warranties of merchantability and ﬁ tness 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.

TECHNICAL SUPPORT & CONTACT INFORMATION

WAVELE

GTH

ELECTRONICS

51 Evergreen Drive

Bozeman, Montana 59771

406-587-4910 (tel) 406-587-4911 (fax)

Sales & Tech Support

sales@teamWavelength.com

techsupport@teamWavelength.com

REVISION HISTORY Document Number:

REVISION DATE NOTES

C 8-Dec-14 Initial Release D 19-Jan-15 Updated Specs

E Apr 2015

KEYWORDS QCL1000, QCL500, QCL1500, QCL2000, quantum cascade laser driver, qcl

laser driver, qcl controller, quantum cascade laser controller

QCL1000-LA400

Updated Transfer Functions,

Fuse Installation

Wavelength Electronics QCL1000 LAB, QCL500 LAB, QCL1500 LAB, QCL2000 LAB User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual