Artifex LDD100-F Series, Original Operating Instructions, Page: 47 / 72

LDD100 Operating Instructions
47 / 72
6.2.5 USB
The communication with the LDD100 is via USB 2.0 with a baud rate of 1 000 000 bit/s. A
hardware-handshake using RTS/CTS is employed to ensure secure communication. The
appropriate USB cable is supplied with the system. The standard cable length is 2m. A 5m
cable may be supplied upon request.
6.2.6 Interlock
This receptacle may be used to connect to an external safety interlock system such as a door
switch. The two terminals of this receptacle must be shorted in order to activate the system. A
shorting block is delivered with the unit to allow use without connecting an external interlock.
6.2.7 Trigger Out
This BNC receptacle may be used for synchronizing external instruments such as a power
meter or a spectrometer. The output is TTL compatible: HI=+5V; LO=0V. The output is HI
when current is driven and LO when not. Several external instruments may be connected to
this receptacle by use of T- or Y-adapters. The outer electrode (shield electrode) is at the
internal ground potential of the LDD100 instrument. Only instruments at the same ground
potential may be connected to this receptacle.
NOTICE!
Note that neither end of the DUT is at ground potential!
The DUT connected to the current output receptacle of the LDD100 is at a
floating, high potential. The anode of the DUT is at the potential of the power
supply (typ12V or +24V). The cathode of the DUT is actively “pulled
down” when driving current to the potential required to drive the current in
question. Thus, it is not possible to connect a single-ended oscilloscope probe
to the DUT and trigger the oscilloscope from the “Trigger Out” receptacle.
Doing so will cause a short circuit and may damage the power supply and/or
the LDD100 unit.
6.2.8 Trigger In
This BNC receptacle may be used for externally activating the current driving sequence.
NOTICE!
Note that neither end of the DUT is at ground potential!
The DUT connected to the current output receptacle of the LDD100 is at a
floating, high potential. The anode of the DUT is at the potential of the power
supply (typ12V or +24V). The cathode of the DUT is actively “pulled
down” when driving current to the potential required to drive the current in
question. Thus, it is not possible to connect a single-ended oscilloscope probe
to the DUT and trigger the oscilloscope from the source connected to the
“Trigger In” receptacle. Doing so will cause a short circuit and may damage
the power supply and/or the LDD100 unit.