Evaluation Engineering - 14

MODULAR TEST

Nicholas Piotrowski, product manager
at Ikonix USA, defined "modular test" as a
test setup that allows the user to add test
points to the system to expand production and/or capability. He cited several
modular architectures the company supports, including the OMNIA II 8204/54
Series electrical safety compliance analyzer from the company's Associated

Sponsored by

16 channels for multipoint ground bond
and/or hipot testing. "A master module
can be linked with up to four slave modules to get up to 80 channels," he said.
"Any number of masters can be added to
the system for an infinite number of test
points if need be."
Vitrek applies the concept of modularity to its power analyzers, such as

discharge section, and one for the output. While nearly all PAs provide versions
that can handle either single-phase or
multiple-phase inputs, Vitrek's modular
approach integrates separate PAs into a
single instrument. Vitrek calls this approach VPA. The VPA (for "Virtual Power
Analyzer") turns each channel in the instrument into an individual PA channel.
Channels can be combined, enabling a
single device in some applications to perform the work of multiple instruments."

Design for test

Ikonix Associated Research OMNIA II Series electrical safety compliance analyzer.

Research Division in combination with
the 620L LineCHEK II leakage tester. "The
OMNIA II 8204/54 allows for groundbond, AC/DC-hipot, and insulation-resistance testing," he said. "The addition
of the 620L expands the electrical safety
testing capability to include LCT (leakage
current testing) to test leakage current
in product insulation while the device is
operating."
Piotrowski also described the company's SC6540 scanning matrix as
"completely modular," offering eight to

the Model PA900. "Many applications
require the use of multiple PAs to accomplish the task at hand," said Chad
Clark, Vitrek's VP of sales and marketing. "For example, testing the efficiency
of a power-conversion system along with
studying parameters like input power
factor and output harmonics would
require two analyzers-one for the input and one for the output. As another
example, fully characterizing a doubleconversion UPS requires three PAs-one
for the input, one for the battery charge/

Vitrek Model PA900
power analyzers.

14

EVALUATION ENGINEERING MAY/JUNE 2020

Jay Jahangiri, product manager, Tessent
ATPG and compression products for
Mentor, a Siemens Business, addressed
modularity with respect to the company's Tessent family of semiconductor
design-for test software products. "In
the context of DFT used by chip designers, modular test refers to the approach
of segmenting the design into smaller
modules for DFT," he said. "Similar to
the divide-and-conquer approach of
tester instruments, the chip design is
broken down to allow performing DFT
tasks such as test logic insertion and
pattern generation on smaller portions
of the design."
Jahangiri said that historically modular test referred to performing DFT at
lower design levels (or cores), but often
work was done from the chip level, which
still required the entire chip design to be
loaded into the tools. "Today's 'modular
test' is better described as 'hierarchical
test,' which is the practice of inserting
test logic and creating retargetable test
at lower design levels and being able to
verify and sign off all DFT work early in
the design flow," he said, adding that the
approach allows for DFT work to be performed on cores concurrently and much
earlier than when the full chip-level design becomes available.
"In addition to improvements in implementation, hierarchical DFT provides
significant reduction in pattern count
and test time, diagnosis costs, machine
resources, and more," Jahangiri said.
"Furthermore, an optimal hierarchical
DFT flow takes DFT out of the critical
path and is able to easily handle latestage design changes (ECOs)."
http://go-asg.gigatronics.com
Evaluation Engineering

Table of Contents for the Digital Edition of Evaluation Engineering
