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CompactPCI DUT Board
The CompactPCI DUT board interfaces the
RCT-II to any Compact PCI daughter board. The cPCI DUT
interface enables more fault coverage than boundary-scan
alone. With boundary-scan only, critical
signals from the cPCI bus connect to BGAs on the cPCI card go
untested. Digital driver/sensors are needed on
the I/O connector in order to test for opens to BGAs during
boundary-scan tests. A 4 wire test only provides IC to IC
interconnects leaving out critical tests for signals going
off-board. Intellitech's ATPG tool will produce test vectors
with both serial patterns and direct digital I/O patterns to fully
test both boundary-scan and edge connector nets.
"We're going to just plug the cPCI card into the backplane
and use a 1149.1 header to test our cards"
On the surface this may sound like a good idea, however, any cPCI
card nets that go to the backplane will not be tested for
opens. Further fault coverage is suppressed if the cPCI
system is operational. During interconnect testing the signals
connected to the backplane will not be tested for shorts or opens
since the functional operation will interfere with the
test. Only the RCT-II and cPCI DUT card can give you
full interconnect testing without building an ICT fixture.
Using the cPCI backplane also can be a problem as nothing
will limit the current to the cPCI board. Critical faults can
be present that will not become apparent until 1149.1 is
running. The RCT-II power supplies can current limit,
protecting your PCB from undue damage for simple solder faults.
There are two available slots, the left slot is used for the cPCI
card and the right slot is used for the optional transition
card. The cPCI DUT card is essential for testing
interconnect between cPCI card and it's associated transition I/O
card. Many times designers will use the 'user defined'
pins of the cPCI card-Transition card to route their scan-chain to
the transition card. The DUT card and RCT-II fully support
this.
When a transition card is not used in the transition card slot,
the RCT-II I/O that go to that interface can be used as additional
tester pins through cabling to the cPCI card .
The standard CompactPCI interface safely powers the board, connects digital I/O to the daughter cads cPCI bus and drives the 1149.1 signals on the dedicated cPCI TAP pins. (large photo)
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