Architecture of the Series 20 Test Solution
New Solutions Offer Ease of Test in Mixed-Signal
Rather than using the very expensive mixed-signal ATE systems with all the "bells and whistles", the design engineers and test people can now apply modern virtual instrumentation to solve the real problems of mixed signal test - at a fraction of the costs and efforts.
The new integration method for instrumentation, IntegraTEST, allows people to apply sophisticated test solutions to difficult mixed-signal test problems without having to undergo a lengthy and costly training. IntegraTEST allows difficult mixed-signal test problems to become simple.
Instead of relying on large full-featured, multipurpose functional ATE test systems, the trend is to use application focussed testers. Such testers may be configured from a set of subsystems to fit the needs of the user and thereby providing substantial cost savings by avoiding superfluous test resources.
The IntegraTEST Series 20 mixed-signal test system is a general purpose functional/parametric system tailored for production tests and verification of mixed-signal ICs, PC-Board and modules.
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Example of the IntegraTEST mixed-signal test solution. In one compact rack VXI, PXI and GPIB instruments are combined into one powerful test system. |
Mixed-signal testing is more than just combining some analogue and digital instruments
in the same system. Besides synchronisation between the instruments, a completely new type
of signals is introduced: the digitized analogue.
Especially for the digital subsystem, these signals have some very unique features,
normally not found in digital test solutions. The IntegraTEST solution fully supports the
mixed-signal test concepts.
A Focused Test System Architecture
The mixed-signal test solution is a complete test system, tailored to the specific needs of particular applications. Each system can be customised from a variety of high performance standard test instrument modules.
The sub-systems are integrated in one coherent system solution, providing a true
mixed-signal test and verification solution. This combined solution offers the
flexibility, openness, fidelity, and cost performance so important in mixed-signal
testing.
CompactPCI and PXI
CompactPCI is an adaption of the Peripheral Component Interconnect Specification for industrial applications, requiring a more robust solution than ordinary desktop PCs. CompactPCI uses industry standard mechanical components and high performance connectors to provide an optimized system intended for rugged applications. CompactPCI provides a system that is electrically compatible with the PCI specification, allowing low cost PCI components to be utilized. PXI is an extension to the PCI bus, defined by National Instruments, adding features otherwise found in VXI. The IntegraTEST solution makes use of PXI as the system controller.
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General software structure of the system. In SequenTEST, test programs are written and executed. SequenTEST calls a number of InstruWARE subsystems (Virtual Instruments). Which subsystems, that are available, depends on the actual system configuration. SequenTEST may also interchange signals with the waveform editor WaveMAKE, save results for analysis in the MultiLyzer and log results for the database HandyBase. |
The preferred type of instrumentation, where performance, test execution speed, and close
integration are at stake, is VXIbus based instrumentation. Other instrumentation needs may
be met with GPIB, PXI, CompactPCI and RS232 controlled instruments, e.g. for power
supplies, for special V/I sources (SMUs), electronic loads, etc.
The open system architecture is of advantage to the user. He or she no longer has to
equip a system solution up front to meet possible, not clearly defined future needs. A
system can now easily be upgraded, if or when changing needs or new requirements devel
op. Due to the high flexibility of the system architecture (software as well as hardware),
the system concept lends itself extremely well for customised solutions, offering lower
costs, higher performance and application specific program
Coherent Testing
Coherency refers to a system that must have its frequency and time functions programmable related in integer-number ratios. The trivial case of coherency is the condition where everything runs at the same rate. However, in the IntegraTEST terms, coherency means a condition, in which test resources are allowed to run at a different rate, if required, and yet be completely time coordinated by the user. This may lead to significantly improved measurement quality.
Software
Probably the most dominant factor in a modern, efficient mixed-signal test system is the software, and the software tools supporting the test. Today's complexity of test modules, and the need for extensive DSP based testing have made it imperative to have elaborate support from such software tools.
The IntegraTEST system environment includes a number of such very efficient tools. It includes a number of software modules for system control and integration, as well as a number of virtual instruments. Test sequencing, system control, signal generation, link to design environments, limiter functions etc. are some of the more important software tools.
Some of the software tools available are:
- VIM Virtual Instrument Manger.
- WaveMAKE Waveform editor & viewer.
- SequenTEST Test sequencer tool
- LimiTEST Limiter func- tions.
- InstruWARE Virtual Instruments.
- MultiLYZER Multi function analysers
- HandyBASE Interface to databases.
- LoadSIM Load-board environment simulation
User interfaces are programmed in LabVIEW, and the program source code is available for most functions where the user has a need to change system functionality.
Controller - UNIX or Windows ?
The system may be controlled in a number of different ways:
The embedded PXI computer may be used as a controller. A monitor, mouse and keyboard can be attached. Hence it can form a fully stand-alone solution.
An external PC running Windows can be used. This solution has the advantage that it is fully network transparent and can easily be used over a local network or even a dial or internet based connection. This is possible because all the data intensive work is done in the embedded PC controller.
The system can also be used with an external SUN computer. This is typically the right setup for an environment that is closely linked to an IC design group. Most IC design systems are still Unix based.
Calibration and Selftest
The IntegraTEST solution adds selftest and calibration to the system. The system is delivered with a set of selftest procedures for the entire system that verify the instrumentation, interconnections and the fixture. The selftest is active using a special selftest adapter, for example a loadboard, that includes relays, components for verification of calibration and interconnections.
Standard instrumentation is very seldom specified with respect to calibration between instruments. For instance, if two waveform generators of different types are used, there is no guarantee that the output will appear synchronized to each other. The IntegraTEST solution may include calibration procedures for this. By performing calibration at the test fixture, the test signals can be aligned in the time-domain.
