Insights

Selecting the right system for parallelism test

2021-09-20  |  10 min read 

This is a continuation of my earlier discussions about parallelism test for automotive printed circuit board assemblies. We’ve talked about the mechanical differences between the FlexiCore and the i7090 in-circuit test (ICT) systems. Today, let’s shift the discussion to focus on the software of the systems.

These days, software makes up a key part of any design and test solution. You can design a test system with a wide range of capabilities, but at the end of the day, it’s the software that turns ‘capabilities into reality’. Software enables flexibility and ease of use. Both factors play major roles in the overall user experience.

In this post, we will compare the different software offered on the FlexiCore and i7090, and how these affect the way user operates the system.

Both the FlexiCore and i7090 are multi-core automated inline test systems, which consist of the test operations and the automated inline controls.

Parallel In-Circuit Test Operations

Software applications control the test operations. They switch the pin card relays and connect different test points on the device under test (DUT) to the measurement module. A user-developed test program tells it which points to connect, and what to measure. This is called a test executive application.

For ICT, test executive application is usually exclusive to the manufacturer of the test system. This is due to the intellectual property rights to the hardware design and control which differentiate the test capabilities between competitors.

FlexiCore uses the i1000 ICT hardware for in-circuit tests. Naturally, the FlexiCore leverages on the i1000 test software for control. This controls the lower-level test operations running within each test core of the system. There will be multiple copies of the i1000 software running independently at the same time in this case. Wrapping all these together is a test executive application called In-Circuit Parallel Test (ICPT) software. ICPT manages the operation of each of the i1000 software cores in synchronization with the handler board movements.

FlexiCore In-circuit Parallel Test software interface

The independent i1000 software cores provide the flexibility to load test programs of different board types on each core and execute all of them in parallel. Especially useful in testing different products in parallel, like in the case of automotive dashboard and lighting panels which consists of different printed circuit board assembly (PCBA). Because each of the PCBA is different, their test program will be different. Most test systems will have to test them sequentially in this case because there is only one test executive application controlling the operation. For the FlexiCore, it runs up to four independent test executives, each capable of handling a unique test program.

With four independent test executives, it provides a great deal of flexibility for user to mix and match different groups of products into each core. The drawback is that four cores is the maximum you can go. For smaller-sized products like camera and sensors that has high board count per panel, each core tests multiple board sequentially.

On the other hand, the i7090 boosts a massive 20-core parallel structure, pushing parallelism test to a whole new level. High board count panel products benefit from this as the test time savings are tremendous. The i7090 maintains a single test executive structure and can control up to a maximum of 20 cores in the system for parallel testing. The software structure is simpler than the FlexiCore where user needs to work with different applications on the system. With a single test executive application, it is more user friendly and easier to operate in general.

The i7090 works with a single test program which holds the tests for all the assigned cores. It requires that all boards tested in each core to be of the same type. Tests are inter-linked and executed together across all cores. Changes in test parameters updates automatically across all boards in the program makes test debugging much easier, unlike the FlexiCore where user needs to manually apply the changes to each of the programs in the cores.

i7090 software interface

Overall, the i7090 test executive software is well integrated and operates seamlessly to control handler and test operations with high parallelism count. It provides ease of use for novice users to quickly get up to speed and deliver a working test solution with a short learning cycle.

i7090 offers high parallelism capability and a user-friendly software environment while the FlexiCore provides flexibility with parallel heterogenous panel test with its independent test executive and handler control application. Depending on the kind of product that you are considering, each of the system has its own set of benefits that may fit the user’s needs.

System Control DLL for 3rd party executive integration and control

Functional test (FCT) is a general term that covers a wide scope of test methods, including high voltage/current measurements, load simulations, communications tests, and device programming. These usually require unique and highly customized test sequences and instruments. Because of the unpredictable combinations of instruments and test sequences involved, it is impossible to use a generic test sequence to execute FCT tests.

FCT test developers create test sequences that are unique for each project. This forms the primary test sequence. Handler operation control and ICT test execution is just another instrument control step among the others that makes up the test sequence. The handler and ICT controls can be viewed as just another instrument in the developer’s test arsenal. The developer can create a test sequence that controls multiple sets of these instruments, performing different operations at the same time. The primary FCT test sequence has overall control over the handler and ICT test operations. It’s all up to the creativity of the developer.

The i7090 system controls use dynamic linked library(DLL) system. The DLL comprises a comprehensive set of functions for controlling the handler and the ICT test execution. The user can use a third party executive application to load the DLL into its tests, and easily control the i7090 operations. FlexiCore uses local area network (LAN) for remote control operations. In most cases, both FCT executive and the FlexiCore applications reside in the same PC and communicate internally over transmission control protocol/internet protocol (TCPIP) socket port. If the need arises, the FCT executive can be located remotely on a different computer, and still be able to maintain the same controls to the FlexiCore over the LAN.

Making this possible are two applications in the FlexiCore system. The Handler Control Panel application controls the handler operations, and the i1000 test application controls the ICT test operations. Both applications maintain a TCPIP server to accept external control links from any applications that supports TCPIP socket communications. Once linked up, FCT executives can control the FlexiCore operations with a detailed list of simple commands.

In general, the i7090 and the FlexiCore each has its own merits to suit various production requirements. All it takes is a closer look and understanding of the systems. When in doubt, all you need to do is ask!

Until the next post, stay healthy and safe!

Ping me up with your questions or comments !

kwan-wee_lee@keysight.com