THORLABS ITC502 User manual

Operation Manual
Thorlabs Instrumentation
Laser Diode Combi Controller
ITC502 (-IEEE)
ITC510 (-IEEE)
2006

Version: 2.16
Date: 25.07.2006
Copyright©2006, Thorlabs

Contents page
1General description of the ITC5xx controller 1
1.1 Packing List 1
1.2 Safety 1
1.3 Features 4
1.4 Mode of operation 6
1.5 Technical Data 7
1.5.1 Technical data ITC502 7
1.5.2 Technical data ITC510 10
1.6 Operating elements at the front panel 14
1.7 Operating elements at the rear panel 15
1.8 Pre-settings 16
1.8.1 Setting the limit of the laser current ILD LIM 16
1.8.2 Setting the limit value of the TEC current 16
1.8.3 Setting the temperature window 16
1.8.4 DIP switch for “wake up“ preset 17
1.9 Connecting components 20
1.9.1 Pin assignment for the laser diode output 20
1.9.2 Pin assignment of the TEC output jack 22
1.9.3 Connecting a thermistor 23
1.9.4 Connecting a temperature sensor AD590 or AD592 24
1.9.5 Connecting a temperature sensor LM135 or LM335 25
1.9.6 Connecting a TEC element 25
1.9.7 Connecting the status indicator 27
1.9.8 Connecting laser- and monitor diode 27
1.9.9 Connecting interlock and status LED 29
1.9.10 Temperature tune input 30
2Operating the ITC5xx 31
2.1 Mains voltage selector 31
2.2 Mains switch 31
2.3 Main setting knobs 31
2.4 Display 32
2.5 Select the value to be displayed 33
2.6 Operating Mode of the laser diode (MODE) 34
2.7 Polarity of the laser diode (LD POL) 36
2.8 Polarity of the monitor diode (PD POL) 36
2.9 Bias voltage of the monitor diode (BIAS) 36
2.10 Adjusting the bias voltage of the monitor diode 38

2.11 Adjusting the power display of an internal monitor diode 38
2.12 Temperature window protection 40
2.13 Selecting the temperature sensor 40
2.14 Polarity check of the TEC element 41
2.15 Setup and function of temperature controllers 42
2.15.1 Statements and implications 42
2.15.2 Demands to the ideal temperature control loop 43
2.15.3 Influences on the real temperature control loop 43
2.15.4 PID adjustment 45
2.16 Analog modulation input 48
2.17 Analog output (ILD) 49
2.18 Laser and TEC current ON/OFF 50
2.19 CP gain 51
2.20 BNC connector TEMP OUT 51
2.21 BNC connector Temp tune 52
2.22 Using the interlock input 52
2.22.1 Examples of various protection functions 53
2.23 Laser voltage measurement 54
3Remote control by a PC (ITC5xx-IEEE) 55
3.1 IEEE488 Interface 56
3.1.1 Interface specifications 56
3.1.2 Setting up the Interface 57
3.1.3 Connecting the Instrument 59
3.1.4 IEEE488 bus commands 60
3.2 Before Programming 62
3.2.1 Nomenclature 62
3.2.2 Program and response messages 62
3.2.3 Data format 63
3.3 Common commands and queries 65
3.3.1 Identification query 65
3.3.2 Reset 65
3.3.3 Self-test query 65
3.3.4 Set Operation-complete bit 65
3.3.5 Operation-complete query 66
3.3.6 Wait 66
3.3.7 Event-Status-Enable-Register (ESE) 66
3.3.8 Query Standard-Event-Status-Register (ESR) 66
3.3.9 Service-Request-Enable-Register (SRE) 67
3.3.10 Query Status-Byte-Register (STB) 67

3.4 System command group 68
3.4.1 Answer mode 68
3.4.2 Error-LED mode 68
3.4.3 Querying the error queue 69
3.4.4 Averaging rate 69
3.5 Status command group 70
3.5.1 Query Device-Error-Condition-Register (DEC) 70
3.5.2 Query Device-Error-Event-Register (DEE) 70
3.5.3 Device-Error-Event-Enable-Register (EDE) 70
3.6 ITC5xx specific commands 71
3.6.1 Operation mode (MODE) 71
3.6.2 Laser diode polarity (LDPOL) 71
3.6.3 Photo diode polarity (PDPOL) 72
3.6.4 Reading the state of the temperature protection (TP) 72
3.6.5 Switching the bias voltage on and off (PDBIA) 73
3.6.6 Turn the output on and off (LASER) 74
3.6.7 Reading the laser diode hardware limit (LIMCP) 75
3.6.8 Laser diode current (ILD) 75
3.6.9 Monitor diode current (IMD) 76
3.6.10 Calibrating a photo diode (CALPD) 77
3.6.11 Optical power (POPT) 78
3.6.12 Reading the optical power from the display (POPTP) 79
3.6.13 Reading the laser diode voltage (VLD) 79
3.6.14 Reading the bias voltage (VBIAS) 79
3.6.15 Temperature Sensor (SENS) 80
3.6.16 Switching the TEC on and off (TEC) 80
3.6.17 Temperature (only AD590) (TEMP) 81
3.6.18 Resistance of the thermistor (RESI) 82
3.6.19 Reading the TEC current hardware limit (LIMTP) 83
3.6.20 Reading the TEC current (ITE) 83
3.6.21 Reading the temperature/resistance window (WIN) 83
3.6.22 Reading the TEC voltage (VTE) 83
3.7 Error messages of the ITC5xx 84
3.7.1 General errors 84
3.7.2 ITC5xx operation error messages 87
3.8 Status reporting 90
3.8.1 Standard event status register (ESR) 90
3.8.2 Standard event status enable register (ESE) 93
3.8.3 Status byte register (STB) 93

3.8.4 Service request enable register (SRE) 94
3.8.5 Reading the STB by detecting SRQ 94
3.8.6 Reading the STB by *STB? command 94
3.8.7 Reading the STB by serial poll 94
3.8.8 Device error condition register (DEC) 95
3.8.9 Device error event register (DEE) 96
3.8.10 Device error event enable register (EDE) 96
3.9 Hints for setting up control programs 97
4Maintenance 100
4.1 Repair 100
4.2 Cleaning 100
4.3 Selecting the line voltage 100
4.4 Exchanging the line fuse 101
4.5 Trouble-shooting 103
5Service 106
5.1 Exchange of internal fuses 106
6Appendix 107
6.1 Warranty 107
6.2 Certifications and compliances 108
6.3 Thorlabs “End of Life” policy (WEEE) 109
6.3.1 Waste treatment on your own responsibility 110
6.3.2 Ecological background 110
6.4 List of acronyms 111
6.5 List of figures 113
7Addresses 114

We aim to develop and produce the best solution for your application in the
field of optical measurement technique. To help us to come up to your
expectations and develop our products permanently we need your ideas and
suggestions. Therefore, please let us know about possible criticism or ideas.
We and our international partners are looking forward to hearing from you.
Thorlabs
This operation manual contains specific information on how to operate the laser
diode controller ITC502 and ITC510. A general description is followed by
explanations of how to operate the unit manually. You will also find informations
about remote control via the IEEE 488 computer interface.
Attention
This manual contains “WARNINGS” and “ATTENTION” label in this
form to indicate dangers for persons or possible damage of
equipment.
Please read these advises carefully!
NOTE
This manual also contains “NOTES” and “HINTS” written in this form.

1.1 Packing List
ITC500 / page 1
1 General description of the ITC5xx controller
1.1 Packing List
1 ITC502 or ITC510 packed in plastic form parts
1 power cord, connector according to ordering country
1 operation manual
1 CD-ROM with Drivers (for ITC5xx-IEEE)
1 Connection cable CAB 400
1 Connection cable CAB 420-15
1.2 Safety
Attention 
All statements regarding safety of operation and technical data in
this instruction manual will only apply when the unit is operated
correctly.
Before applying power to your ITC5xx system, make sure that the
protective conductor of the 3 conductor mains power cord is
correctly connected to the protective earth contact of the socket
outlet!
Improper grounding can cause electric shock with damage to your
health or even death!
Also make sure that the line voltage setting marked on the rear panel
agrees with your local supply and that the corresponding fuses are
inserted. If not, please change the voltage (see 4.3) and.
the mains fuse (see section 4.4)
Prior to operation make sure that the correct line voltage is set and
the appropriate fuse inserted.
All in- or outputs must only be operated with duly shielded
connection cables.

1.2 Safety
ITC500 / page 2
Only with written consent from Thorlabs may changes to single
components be carried out or components not supplied by Thorlabs
be used.
This precision device is only dispatchable if duly packed into the
complete original packaging including the plastic form parts. If
necessary, ask for a replacement package.
Attention 
Semiconductor laser modules can deliver up to several 100mW of
(maybe) invisible laser radiation!
When operated incorrectly, this can cause severe damage to your
eyes and health!
Be sure to pay strict attention to the safety recommendations of the
appropriate laser safety class!
This laser safety class is marked on your external laser source used.
Attention 
Mobile telephones, handy phones or other radio transmitters are not
to be used within the range of three meters of this unit since the
electromagnetic field intensity may then exceed the maximum
allowed disturbance values according to EN 50 082-1.
To connect the unit to the mains, only use the supplied mains cable
with safety mains plug. The unit is grounded via the protective
conductor of this cable. To avoid electrical shock the plug of the
mains cable is to be inserted into a correctly grounded socket.

1.2 Safety
ITC500 / page 3
To guarantee a safe operation of the ITC5xx always pay attention to keep the
ventilation slots on the sides and the fan air inlet at the rear of the unit free from
obstacles.
Attention 
The unit must not be operated in explosion endangered
environments!
The user must not open the unit during operation. An internal adjustment as well as a
replacement of parts is only to be carried out by respectively trained service
personnel. Parts must not be exchanged when the unit is switched on.
Dangerous voltages may even be present with the unit off line and the power cord
removed!.

1.3 Features
ITC500 / page 4
1.3 Features
•Key-operated power switch
Protection against unauthorized or accidental use.
•Defined states after switch-on
When switching on the ITC5xx with the mains switch the laser and TEC current
outputs are always switched off. The ITC5xx will always wake up in a mode that
can be selected via a DIP switch at the rear.
•Softstart
The switch on delay of the softstart function protects the laser diode against
undesired transients.
•Limit for the laser diode- and the TEC current (hardware limit)
Manually adjustable current limits restrict the maximum allowed current. The limit
values are set with two 25-turn potentiometers at the front panel.
•Interlock
The interlock input realizes several protective functions simultaneously.
•Safety lock to prevent unintentional use
•Cable damage monitoring
•An external emergency switch may be connected
•Application of external automatic protection equipment, e.g. for the temperature
of cooling water
•ON/OFF LED of the laser diode
The laser can only be operated with the interlock input being duly closed.
•Contact protection of the laser diode (open circuit)
If the cable connecting the laser should be interrupted even for a short time during
operation, an emergency switch turns off laser current immediately.
•Contact failure display of the TEC element (open circuit)
Cable damage, bad contact or too high resistive TEC element is displayed with a
LED. The output will remain switched on since also a wrong TEC element can still
provide cooling and thus further protects the laser diode.

1.3 Features
ITC500 / page 5
•Protection of the DUT against sensor failure
Protection against use of an incorrect temperature sensor / protection against line
interruption to the temperature sensor.
•Electronic short-circuit switch for the laser diode
With the current module off an electronic switch will short-circuit the laser diode to
protect against static discharges etc.
•Control LED of laser- and TEC current being active
If the current is switched on an LED lights up to indicate device is on.
•Temperature window protection of the laser diode
Operation in a specified temperature range.
•Over-temperature protection
The ITC5xx contains an automatic over-temperature protection in case that the
allowed internal operating temperature of the ITC5xx should be exceeded. In this
case the output is turned off. After internal temperature drop of about 10 °C the
output current of the ITC5xx can be switched on again.
•Mains filter
Protection against line failures (protection against transients) and other
electromagnetic interference's.
•Line failure monitoring
In case of line failure/line interruption the ITC5xx will wake up again with the laser
output switched off.

1.4 Mode of operation
ITC500 / page 6
1.4 Mode of operation
A fixed adjustable hardware limit limits the maximum deliverable laser current in each
operating mode.
The laser diode is sourced unipolar against ground (anode or cathode to ground may
be selected). This is of advantage regarding the stability of the laser current, noise
and RF influences.
The monitor diode input is a transimpedance amplifier (input impedance 0 Ω). Both
polarities of the monitor diode can be selected. The monitor diode may either be
operated photovoltaic (without bias voltage) or photoconductive, i.e. with bias voltage
(selectable in a range from 0 ... 10 V).
The limit value for the TEC current and the temperature window are set with screw-
driver potentiometers.
The TEC element always operates against ground. This is of considerable advantage
regarding the safety of the TEC element and the stability of the TEC current.
The sensor input is designed for different types of temperature sensors.
A missing sensor or the selection of a incorrect type will be detected.
The ITC5xx has an input for an IC temperature sensor of the AD590/592 or
LM35/135/335 series as well as an input for a thermistor. If a thermistor is used you
can choose between two resistance ranges (maximum resistance of the thermistor
20 kΩor 200kΩ).
The set values for the temperature and the thermistor resistance are set with the 10-
turn main dial knob.
The P-, I- and D-share of the analog control loop are set with „thumb-nail“-
potentiometers.
All settings are done by the operating elements or via the IEEE488-interface (ITC5xx-
IEEE) and a PC. Only the hardware limits for the currents must be set manually. No
manual settings are required during automatic tests using a PC.

1.5 Technical Data
ITC500 / page 7
1.5 Technical Data
(The technical data are valid at 23 ± 5°C and 45 ±15% rel. humidity)
1.5.1 Technical data ITC502
General Data
Line voltage 100 V / 115 V / 230 V (-10%, +15 %) (fixed)
Line frequency 50 ... 60 Hz
Max. power consumption 90 VA
Supply mains overvoltage Category II (Cat II)
Operating temperature 1) 0 ... +40°C
Storage temperature -40°C ... +70°C
Relative Humidity Max. 80% up to 31°C, decreasing to 50% at 40 °C
Pollution Degree (indoor use only) 2
Warm up time for rated accuracy ≤10 min
Operation altitude < 3000 m
Weight <7 kg
Dimensions (W x H x D) including operating elements 220 x 120 x 376 mm3
without operating elements 220 x 110 x 351 mm3
Current control
Range of laser current ILD 0 ... ±200 mA
Compliance voltage >6 V
Setting resolution (manual / remote control) 10 µA / 3 µA
Measurement resolution (manual / remote control) 10 µA / 1 µA
Accuracy ±100 µA
Noise without ripple (10 Hz ... 10 MHz, rms), typ. <1.5 µA
Ripple (50/60 Hz, rms), typ. <1.5 µA
Transients, typ. <0.2 mA
Drift, 24 hours, typ. (0…10Hz, without changing the ambient temperature) <10 µA
Temperature coefficient ≤50 ppm/°C
Power control
Range of monitor current IPD 5 µA ... 2 mA 2)
Setting resolution (manual / remote control) 0.1 µA / 0.03 µA
1) non condensing
2) other ranges on request

1.5 Technical Data
ITC500 / page 8
Measurement resolution (manual / remote control) 0.1 µA / 0.01 µA
Accuracy ±2 µA
Photodiode bias voltage 0 ... 10 V
Laser voltage
Measurement principle 4-wire
Measurement range 0 ... 10 V
Measurement resolution (manual / remote control) 1 mV / 0.1 mV
Accuracy ±20 mV
Analog control output
Load resistance ≥10 kΩ
Output voltage for 0 ... ILD MAX 0 ... ±10 V 1)
Transmission coefficient 50 V/A ± 5%
LD Current limit
Setting range ILIM 0 ... ≥200 mA
Measurement resolution (manual / remote control) 10 µA / 1 µA
Accuracy ±0.5 mA
Analog modulation input
Input impedance 10 kΩ
Small signal 3 dB bandwidth (CC mode) DC ... 500 kHz
Laser diode modulation coefficient (CC mode) 20 mA/V ± 5%
Laser diode modulation coefficient (CP mode) 0.2 mA/V ± 5%
Current output TEC element
Control range - 2 A ... + 2 A
Maximum output power 16 W
Compliance voltage >8 V
Measurement resolution (manual / remote control) 1 mA / 0.1 mA
Measurement accuracy ± 10 mA
Noise and ripple (typ.) <1 mA
Measurement resolution TEC voltage (manual / remote control) 1 mV / 0.1 mV
Measurement accuracy TEC voltage ± 40 mV
1) sign depends on selected polarity

1.5 Technical Data
ITC500 / page 9
TEC Current limit
Setting range 0 ... ≥2 A
Measurement resolution (manual / remote control) 1 mA / 0.1 mA
Accuracy ±20 mA
Temperature sensors AD590, AD592, LM135, LM335
Control range (AD590, LM135) - 45 °C ... + 145 °C
Control range (AD592) - 25 °C ... + 105 °C
Control range (LM335) - 40 °C ... + 100 °C
Setting resolution (manual / remote control) 0.01 °C / 0.003 °C
Measurement resolution (manual / remote control) 0.01 °C / 0.001 °C
Accuracy ±0.1 °C
Temperature stability (24 hours) ≤0.001 °C
Thermistor (2 kΩ/ 20 kΩrange)
Measurement current 100µA / 10 µA
Control range 10 Ω... 19.99 kΩ/ 100 Ω... 199.9 kΩ
Setting resolution (manual control) 1 Ω/ 10 Ω
Setting resolution (remote control) 0.3 Ω/ 3 Ω
Measurement resolution (manual control) 1 Ω/ 10 Ω
Measurement resolution (remote control) 0.1 Ω/ 1 Ω
Accuracy ±5 Ω/ ±50 Ω
Temperature stability (24 hours) 1) ≤0.5 Ω/ ≤5 Ω
Temperature control input
Input resistance 10 kΩ
Control voltage -10 ... +10 V
Transmission coefficient IC-sensors 2 °C/V ±5%
Transmission coefficient thermistor (20 kΩ/ 200 kΩrange) 0.2 kΩ/V / 2 kΩ/V ±5%
1) Due to the nonlinear conversion from Ωto °C the stability in °C depends on the operating conditions
and the characteristics of the thermistor. E.g. for a typical thermistor at a set point of 10kΩ(25°C), a
0.5Ωstability translates into about 1mK temperature stability. At a set point of 5kΩ(38°C), the stability
is about 2mK.

1.5 Technical Data
ITC500 / page 10
Temperature control Output
Load resistance >10 kΩ
Output voltage 0 ... ±10 V
Transmission coefficient IC sensors 50 mV / °C ± 5%
Transmission coeff. thermistor (20 kΩ/ 200 kΩrange) 500 mV/ kΩ/ 50 mV/kΩ± 5%
Temperature window protection
Setting range TWIN 0.5 °C ... 20 °C
Setting range RWIN (20 kΩ/ 200 kΩrange) 50 Ω... 2 kΩ/ 500 Ω... 20 kΩ
Computer Interface
Setting resolution 16 Bit
Measurement resolution 12 ... 18 Bit 1)
1.5.2 Technical data ITC510
General Data
Line voltage 100 V / 115 V / 230 V (-10%, +15 %) (fixed)
Line frequency 50 ... 60 Hz
Max. power consumption 150 VA
Supply mains overvoltage Overvoltage category II (Cat II)
Operating temperature 20 ... +40°C
Storage temperature -40°C ... +70°C
Relative Humidity Max. 80% up to 31°C, decreasing to 50% at 40 °C
Operation altitude < 3000 m
Pollution Degree (indoor use only) 2
Warm up time for rated accuracy ≤10 min
Weight <7 kg
Dimensions 220 x 120 x 377 mm3
1) in High Resolution mode, at reduced measurement speed
2) non condensing

1.5 Technical Data
ITC500 / page 11
Current control
Range of laser current ILD 0 ... ±1 A
Compliance voltage >6 V
Setting resolution (manual / remote control) 100 µA / 15 µA
Measurement resolution (manual / remote control) 100 µA / 10 µA
Accuracy ±1 mA
Noise without ripple (10 Hz ... 10 MHz, rms, typ.) <5 µA
Ripple (50/60 Hz, rms, typ.) <3 µA
Transients (typ.) <1 mA
Drift (24 hours, 0…10Hz, at constant ambient temperature, typ.) <30 µA
Temperature coefficient ≤50 ppm/°C
Power control
Range of monitor current IPD 5 µA ... 2 mA 1)
Setting resolution (manual / remote control) 0.1 µA / 0.03 µA
Measurement resolution (manual / remote control) 0.1 µA / 0.01 µA
Accuracy ±2 µA
Photodiode bias voltage 0 ... 10 V
Laser voltage
Measurement principle 4-wire
Measurement range 0 ... 10 V
Measurement resolution (manual / remote control) 1 mV / 0.1 mV
Accuracy ±20 mV
Analog control output
Load resistance ≥10 kΩ
Output voltage for 0 ... ILD MAX 0 ... ±10 V 2)
Transmission coefficient 10 V/A ± 5%
LD Current limit
Setting range ILIM 0 ... ≥1 A
Measurement resolution (manual / remote control) 100 µA / 10 µA
Accuracy ±2.5 mA
1) other ranges on request
2) sign depends on selected polarity

1.5 Technical Data
ITC500 / page 12
Analog modulation input
Input impedance 10 kΩ
Small signal 3 dB bandwidth (CC mode) DC ... 200 kHz
Laser diode modulation coefficient (CC mode) 100 mA/V ± 5%
Laser diode modulation coefficient (CP mode) 0.2 mA/V ± 5%
Current output TEC element
Control range - 4 A ... + 4 A
Maximum output power 32 W
Compliance voltage >8 V
Measurement resolution (manual / remote control) 1 mA / 0.1 mA
Measurement accuracy ± 20 mA
Noise and ripple (typ.) <2 mA
Measurement resolution TEC voltage (manual / remote control) 1 mV / 0.1 mV
Measurement accuracy TEC voltage ± 40 mV
TEC Current limit
Setting range 0 ... ≥4 A
Measurement resolution (manual / remote control) 1 mA / 0.1 mA
Accuracy ±40 mA
Temperature sensors AD590, AD592, LM135, LM335
Control range (AD590, LM135) - 45 °C ... + 145 °C
Control range (AD592) - 25 °C ... + 105 °C
Control range (LM335) - 40 °C ... + 100 °C
Setting resolution (manual / remote control) 0.01 °C / 0.003 °C
Measurement resolution (manual / remote control) 0.01 °C / 0.001 °C
Accuracy ±0.1 °C
Temperature stability (24 hours) ≤0.001 °C