Building an ITA

Once the design for an Interface Test Adapter (ITA) has been completed using NODES™, the actual construction of the ITA can start.

 

 

There are a number of important factors which must be considered before and during the construction of an ITA.  These are as follows:

 

Ø     Build quality is paramount to ensure that any testing carried out and any reported faults are as a result of the UUT and not the ITA.

 

Ø     Recreate the interface connections with the UUT in a configuration that is as fully representative of its normal operating condition as possible.  If environmental stimulus is being applied during testing, then it may also be important to consider the dynamic effects of the ITA.

 

Ø     Design the ITA to ensure that the wire to connector and and wire to wire joints are kept to an absolute minimum; ideally the ITA would consist of, for example for the VIFD™, a 50-way male D-Sub connector soldered to ITA cable conductors and the other end soldered to connector required to connect to UUT.  Where possible solder joints to minimise the possibility of intermittent faults on pin connections within the ITA itself.

 

Ø     The choice of 50-Pin D-Sub connector for use on VIFD™, and the components for the Virginia Panel on IDFIS™, is potentially critical for the build and then the durability of the ITA during testing; see Cable Types for more information.

 

Ø     The length of the ITA cable can be up to 300m without any adverse effect on the IFD™ TE testing capability.

 

Ø     If possible, use shielded cable (not twisted-pair), preferably with screen bonded at the connector, for the VIFD™ as this reduces the effect of EMI in an electrically noisy environment and therefore limits spurious intermittent events that can occur in a noisy EMI environment; shields must be left unconnected at the UUT and must not be tied to 'test ground' on the IFD™ TE.

 

Ø     Make the ITA with strain-relief for longevity

 

Ø     Try and avoid ad-hoc pinouts, crocodile clips, testing probe/s and clips if at all possible as these generally are a major source of intermittent events.

 

 

For the IDFIS™ or VIFD™, the construction of the ITA will be determined by the configuration and construction of the type of UUT that is being interconnected.  For VIFD™, however, in general, the ITA construction would consist of a 50-way cable assembly with a 50-pin D-sub connector at one end and the male/female counterpart to the UUT connections at the other.  Depending on the number of TPs on the UUT, or whether there was a need to separate TPs out on to separate Jacks (J1 to J6 on the VIFD™ top panel) , there could be a number of these assemblies linking the Jack connectors on the VIFD™ to the UUT.

For the IDFIS™, however, the Virginia Panels will form the backbone of the ITA.  Care must be taken on pinning out the Virginia Panel as the pins are closely packed and possible shorts can occur.  Also cable support is paramount to ensure there is strain-relief on the large ITA that general manifest from high test point count.

See details on pin-outs for different connectors: J-Connector Pin-Out and Virginia Panel Pin-Out.