Quantum Composers LDDC 1550 - Manual (Page 5)

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Driver I/O connector pins 13 and 14, it is required that the current be limited to less than 8A by
means of fusing it at 5A. If an external power supply is chosen to be used, it is recommended
that the mains outlet be easily accessible so that the plug of the external power supply can be
easily removed.
Driver Connection
The LDDC/LSC to driver connection in most cases will only require a straight through DB15
connection. Please verify that your particular driver has a compatible pin out. Refer to the
Interface Connection Table for detailed pin out descriptions. A custom cable can be made if
necessary to connect to drivers that do not use the same pin outs as the LDDC/LSC.
WARNING, incorrect connections can damage either the LDDC/LSC or the diode driver.
LSC Connections
The LSC unit has additional connections for q-switch triggering, external triggering, sync output
and additional I/O. The q-sw trigger has an adjustable delay referenced off the falling edge of the
pulse control signal. This allows for optimum adjustment of triggering a q-switch driver. The
external trigger input allows the LSC to be externally triggered via an external source. Rising and
falling edges can be selected as well as various modes. The additional I/O connector offers
additional signals: photodiode input, two thermistor inputs, a 0-10V analog output, a 0-5V
analog input and 3 TTL inputs that can be monitored.
Communication
The LDDC/LSC provides a standard USB connection for remote communications. An optional
Ethernet connection is also available.
USB
When the LDDC/LSC is connected to a remote computer via the USB connection, the computer
will recognize the unit as a “LDDC Controller”. Drivers will need to be installed for the remote
computer to interface to the LDDC/LSC. Drivers are included on the provided CD. Once the
drivers have been installed, the LDDC/LSC will show up in the device manager as a USB to
Serial Port Adapter. The LDDC/LSC can then be communicated with by using any terminal
program. The unit is baud rate independent, so any speed can be selected. Typically a rate of
115,200bps can be used.
Driver Installation (Windows XP)
1. Plug the LDDC/LSC into the computer using a USB cable. Make sure the unit is powered
on.
2. The computer will pop up a message indicating it has found new hardware: “LDDC
Controller”.
3. The new hardware wizard will launch. Check the “Install from a list or specific location”
option and click next.
4. Then select “Search for the best driver in these locations” and check the option to
“Include this location in the search”. Then click the browse button and locate the folder
on the CD where the LDDC/LSC drivers are located. Click next.