TeslatronPT

• 3U high and designed for 19” rack mounting
• 2 x 50 way rear mounted sub-D connectors
  • Connection to the signal lines of the measurement probe or cryostat
  • Feed-through link to connect any of the lines to additional instrumentation (an alternative to using the individual BNC and Twinax on the front panel)
• Unit switches can be used to switch any of the signal lines between signal, measurement ground or protective ground
• Each signal line has a BNC or Twinax port for connection directly to measurement electronics or diagnostics
• High-quality make-before-break switches
  • Low resistance Au contacts
  • Sealed against moisture ingress to avoid future contact corrosion
• Internal signal routings designed to minimise cross-talk
• Line resistance kept to a minimum

During the process of mounting the sample into the sample holder, the ESD plug will be inserted.  This plug links all the electrical connections to the sample together ensuring that no damaging voltages can be generated across the sample due to ESD.  This plug remains in place during transport of the sample holder plus sample, meaning the sample could safely be taken from the sample preparation lab to the measurement lab, or even shipped to a lab in another continent safe from ESD damage.

When mounting the sample holder in the probe, the user keeps the ESD plug in place.  Then connect the probe to the desired measurement instrumentation via the SPSU.  Set the switches of the SPSU to ground all the signal lines to the desired ground, either protective ground or instrument ground.  Once the switches are set correctly, remove the ESD plug from the sample holder.  If appropriate for the sample the user might run some measurement checks to ensure the sample is connected and the signal train is working.  Then the probe can be loaded in the cryostat and cooled to the required temperature.

Once the sample plus probe is inserted in the cryostat and the measurements are in progress, the SPSU can be used as a break-out box to switch or monitor any of the signal lines during the experiment.

The PCB and LCC holders are ceramic Aluminium-Nitride (AlN) to optimise thermal conductivity.

Electrical contact plating is Ni free to minimise the remnant field effects in the sample domain.

The following sample holders are available:

• 20-pin LCC with ESD connector
• 16-pin DIP (dual in-line) connector with ESD connector
• 16 contact pad bare pcb for general purpose with ESD connector
• 44-pin LCC – NO ESD connector as there is not enough space

PCB sample holder interface – 44 non-magnetic spring loaded pins to connect to the sample holder PCB

The measurement cable is a carefully specified cable constructed of 13 twisted pairs, 10 pairs of 26 AWG tinned Cu and 3 pairs of 22 AWG tinned Cu. Each pair is individually screened with a foil screen. Each screen has external insulation to isolate it from all the other screens. Each screen also has a drain wire. 

In addition, the cable has an overall foil screen which has internal insulation plus an external screen braid.  The overall screen also has a drain wire.  This construction facilitates overall screening with the outer screen connected to protective ground but in addition any pair can be screened to a specific measurement ground for that channel. This maximises isolation and minimises cross-talk between single pairs.