Arroyo Instruments LaserSource 4400 Series User manual

Page 2 · 4400 Series LaserSource User’s Manual
Table of Contents
Introduction ...............................................................................................4
Safety Terms and Symbols.......................................................................6
Quick Start ................................................................................................8
Installation .................................................................................................9
Powering Up the Unit............................................................................9
Ventilation .............................................................................................9
Rack Mounting......................................................................................9
Warm-up and Environmental Considerations ....................................10
Front Panel Connections ........................................................................10
Modulation Input.................................................................................10
Trigger Input & Output........................................................................10
Rear Panel Connections .........................................................................11
13W3 Laser Output Connector...........................................................11
Bus Bar Laser Output Connector .......................................................12
Auxiliary Connector ............................................................................13
Interlock Connector ............................................................................13
USB Connector...................................................................................13
RS232 Connector ...............................................................................14
Front Panel Operation.............................................................................14
Main Display Screen...........................................................................16
Using Limits ........................................................................................17
Status Messages ................................................................................17
Settings and Menus ................................................................................18
Main Laser Menu.....................................................................................19
Pilot Laser Menu .....................................................................................24
Remote Mode Operation.........................................................................26
Installing the USB Drivers .......................................................................26
Connecting to the LaserSource ..............................................................26
Grounding Considerations......................................................................27
Cable Wiring for Modulation and QCW ..................................................28
Laser Control Modes...............................................................................29
Modulation..........................................................................................30
Using QCW Modes .................................................................................30
QCW Low Setpoint .............................................................................32
Trigger Input and Trigger Output .......................................................33
Trigger In and Trigger Out Delay........................................................33
Risetime Control .................................................................................33
Using Limits.............................................................................................34

4400 Series LaserSource User’s Manual · Page 3
Using the Cable R Setting.......................................................................34
Measure the Voltage at the Laser.......................................................35
Short the Connection at the End of the Cable ...................................35
How the Calculation Is Used ..............................................................35
Using Remote Voltage Sense .................................................................36
Using Remote Voltage Sense.............................................................36
Using the Auxiliary Interface....................................................................37
Auxiliary Sensors ................................................................................37
Digital Inputs.......................................................................................37
Digital Outputs ....................................................................................38
Relay ...................................................................................................38
Dig Out Modes....................................................................................39
Using the Interlocks ................................................................................40
The Laser Interlock/LED Interface...........................................................40
Closing the Circuit ..............................................................................40
Working With Thermistors.......................................................................41
The Steinhart-Hart Equation ...............................................................42
Analog Modulation..................................................................................42
Optimizing for Pulse Performance ..........................................................44
Cables.................................................................................................44
Lowering BW or Risetime ...................................................................45
Dead Shorts........................................................................................45
Eliminating E-537 (Thermal Overload) Error ......................................45
Eliminating E-540 (Voltage Headroom) Error.....................................46
Eliminating E-505 (Voltage Limit) Error ..............................................46
Eliminating E-541 (Excessive Current Detected) Error.......................46
Noise...................................................................................................47
Voltage Limit / Headroom Disable......................................................47
Using the Pilot Laser ...............................................................................48
Using the Function Keys .........................................................................48
Running a script..................................................................................48
Loading a previously stored configuration.........................................49
User Calibration ......................................................................................50
Specifications..........................................................................................52
Error Messages.......................................................................................59
Maintenance and Service........................................................................61
Maintenance .......................................................................................61
Fuses ..................................................................................................61
Service ................................................................................................62
Warranty..................................................................................................62

Page 4 · 4400 Series LaserSource User’s Manual
Introduction
Thank you for choosing the LaserSource from Arroyo Instruments. Your
LaserSource is a combination of leading-edge technology combined with years
of experience in the field of current control.
With a crystal clear VFD display, both RS232 and USB computer interfaces, and
small footprint, the LaserSource will fit into almost any laser diode control
application.
A key feature of the LaserSource is its optical isolation of both modulation and
photodiode inputs. By isolating these inputs, it prevents unwanted ground loop
problems. No other laser diode driver in the industry has this feature.
Another important feature of the LaserSource is its ability to operate in quasi-
CW (QCW) mode. This mode permits operation of lasers to a higher current and
power, minimizing the thermal load by turning the laser on for only a brief period
of time, taking measurements, then turning off the laser. The LaserSource
supports both internal and external triggering of pulses, and also includes a
trigger out to synchronize the LaserSource with other instruments.
The LaserSource also operates in constant voltage control mode, allowing you
to use it in precision voltage applications, such as EML devices, or for doing V-I
measurement graphs.
The LaserSource includes another feature not found in other products: the
ability to program the photodiode bias level from the front panel or over the
computer interface, to any voltage from 0 to -5V. No more tweaking a
potentiometer with a screwdriver and a DMM. Simply dial in the voltage you
need.
Unlike other laser diode drivers in its class, which use inexpensive 7-segment
displays, the LaserSource takes advantage of its large VFD display to
simultaneously show the set point, laser voltage, and photodiode read back.
The user interface of the LaserSource is engineered to make using the
instrument straightforward. With its text-based menus, there is never any
confusion over which setting is being changed, and parameters are displayed in
clear English (no cryptic numbers or LEDs to decode).
The LaserSource offers all the features you would expect from a modern
precision laser diode driver, including:
10ppm current stability over one hour
10A to 100A current ranges

4400 Series LaserSource User’s Manual · Page 5
Comprehensive laser protection circuitry, including hardware voltage
and current limits, and fast transient shutdown.
External analog modulation
Power mode control, both in photodiode current (AMC) or computed
photodiode power (APC) modes.
Simultaneous reading of current set point, voltage measurement, and
photodiode current or power measurement.
What’s in the Box
Along with the LaserSource itself, a CD with electronic copies of this manual,
the Computer Interfacing Manual, and USB drivers are included. For USA
customers, a power cord is included. For non-USA customers, an IEC-60320-
C13 rated AC power cord must be provided.
Accessories
Arroyo Instruments also sells several accessories designed to work with the
LaserSource. These include:
LaserSource Cables:
o1230: 20A, 2m, 13W3F connector on device end
o1231: 20A, 2m, pigtailed (bare) wires on device end
o1232: 40A, 2m, 13W3F connector on device end
o1233: 40A, 2m, pigtailed (bare) wires on device end
4400/5400 Series 2U Rack Mount Kit (p/n 1403-RM)
For installing your 4400/5400 Series TECSource into a standard 19”
rack.
10kΩThermistor (p/n 1600-10K) for use with the auxiliary temperature
sensor inputs.
RS-232 NULL Cable, 3m (p/n 1200-NULL)
USB Cable, 3m (p/n 1201)

Page 6 · 4400 Series LaserSource User’s Manual
Safety Terms and Symbols
The following safety-related terms are used in this manual:
Warnings (noted by the WARNING heading) explain dangers that
could result in physical injury or death.
Cautions (noted by the CAUTION heading) explain conditions that
could result in damage to the instrument, other equipment, or your
device.
Notes (noted by the NOTES heading) are not safety-related and are
intended simply to point out important information.
If, at any time, any of the following conditions exist, or are suspected of existing,
discontinue use of the unit until it can be inspected by qualified service
personnel:
Visible damage to the unit, including damage or stress caused during
product shipment.
Storage of the unit outside the standard storage temperature or
humidity rating, or prolonged storage under harsh conditions.
Failure to operate properly.
If needed, contact your distributor or Arroyo Instruments for service or repair to
ensure the safety of the product is maintained.
Symbols
Power Off Power On
Caution, refer to manual Earth Ground
Caution, risk of electric shock

4400 Series LaserSource User’s Manual · Page 7
General Warnings
CAUTION
There are no user-serviceable parts inside. All service
and repair work shall be done by Arroyo Instruments or
personnel authorized by Arroyo Instruments.
Modifications done by non-authorized personnel will
void the warranty. Please see the Service section later
in this manual for instructions on how to obtain service
for this instrument.
WARNING
To avoid electrical shock, ensure a 3-prong power cord
is used, and is plugged into an earth-grounded
receptacle. Failure to do so can result in severe injury or
death.
WARNING
Potentially lethal voltages exist within this instrument.
This instrument is intended for use by qualified
personnel who understand the shock and laser hazards
and are familiar with safety procedures required to avoid
injury. Read this manual completely before attempting
to use this product.

Page 8 · 4400 Series LaserSource User’s Manual
Quick Start
The LaserSource was designed with ease of use in mind. This section will show
how you can quickly get the unit up and running.
The unit uses a universal AC input, just ensure you are within the 100V to 250V
AC operating range. Plug the AC cord into the unit and into the wall outlet. Turn
on the power switch located on the front panel, and the unit will power up,
displaying the model information, serial number, and firmware version number.
The most important setting of the controller is the current limit. A proper current
limit will ensure you do not over-drive the laser. The voltage limit is not as critical,
but a well-set voltage limit is also recommended.
Press the Menu button to enter the menu, and using the knob, turn to the right
until the Io Limit setting is displayed. This is perhaps the most critical setting
you can adjust on the instrument, as it will protect your laser against over-current
conditions. Press the knob to edit the setting and adjust the limit as appropriate
to your laser diode. Set a bit above the target operating current, as you do not
want to be driving into the limit. Press the knob again to save the value. Make
the same adjustments to the voltage limit (Vf Limit), setting between 0.5V and
1V above the typical operating voltage of your device (the extra voltage will take
into account any voltage losses in the cables and connectors). Once you have
made all your adjustments, press the Menu button to exit the menu.
Next, connect the cable between your LaserMount or other fixture and the
Output connector of the LaserSource. We recommend using our cables as they
have been designed to work well with the LaserSource. If using your own
cables, ensure they have been properly wired according to the pin-out of the
LaserSource and your fixture.
When starting a system for the first time, it is recommended that you start with
the set point at zero and ramp up the set point to your target operating current.
The “gentle” turn-on is a good way to verify everything is hooked up correctly.
For subsequent turn-ons, you can leave the set point at your target and simply
turn the output on.
After a 3-second delay (defeatable, see On Delay setting), the output will turn on
and you will see the actual voltage of the laser displayed.
Detailed information on the operation of the unit can be found in the remainder
of this manual.

4400 Series LaserSource User’s Manual · Page 9
Installation
Installation of the 4400 LaserSource is very straightforward, as the quick start
section above illustrated. This section will provide additional details and
considerations for installing your LaserSource.
After unpacking the unit, make sure all packing materials have been removed
and nothing obscures the ventilation ports on the back and bottom of the unit.
The LaserSource has a universal input power supply, accepting 90 to 240 VAC,
and 50 or 60 Hz. This covers all conventional power worldwide but ensure your
AC power meets these requirements.
Powering Up the Unit
Connect the AC power cord to the unit. Turn the power switch, located on the
front of the unit, into the on (|) position. The unit will display the current firmware
revision, go through a quick power-up self-test, and return to the last known
operating state.
Ventilation
The LaserSource has vent holes on the side and front of the unit. You must not
block these vent holes or overheating may occur causing damage to the unit.
Rack Mounting
The rack mounting kit (p/n 1403-RM) for standard 19” racks are available for the
LaserSource. Because the unit draws air from the side, and therefore inside the
rack housing, be sure that the internal rack ambient temperature (which will
CAUTION
Do not exceed 250VAC on the line input.
Excessive line voltage can damage the controller.
CAUTION
Do not operate the unit above +40°C ambient, and
ensure the instrument is properly ventilated, or the unit
may overheat and possible damage to the unit may
occur.

Page 10 · 4400 Series LaserSource User’s Manual
typically be several degrees higher than room ambient) does not exceed the
unit’s operating temperature.
Warm-up and Environmental Considerations
In order to achieve the highest level of accuracy, the LaserSource should be
powered on for at least one hour prior to taking measurements. In addition,
ensure that the unit is not operating outside the ambient temperature range or
humidity conditions.
Front Panel Connections
The front panel has connections for modulation and QCW triggers.
Modulation Input
The modulation input BNC accepts a 0V to 10V input signal for analog set point
control of the driver. The modulation input is optically isolated from the rest of
the control circuits in the LaserSource and electrically isolated from ground, so
you should not need to be concerned about ground interference from any
modulation source.
BNC Description
Center Pin Signal+
Shell Signal–
Modulation Connector (BNC)
Trigger Input & Output
The trigger input and output BNCs are used in QCW modes. For more
information on their use, see the Using QCW Modes section.
BNC Description
Center Pin Signal+
Shell Ground
Trigger In and Trigger Out Connectors (BNCs)