In-Circuit Test has been around for a long time. The fundamental components of in-circuit testers haven’t changed by much over the years. Our in-circuit testers come with the following main components as standard features:
- The measurement system is comprised of a precision programmable 4-quadrant DC current/voltage source current/voltage limit. Sense lines provide feedback so that voltage drops can be compensated for. This is specially important in setting up precise guard voltage for guarded measurements. An 8–line measurement bus, a two stage multiplexer, and some relay controlled channels connect the measurement resources to the device under test (DUT) through a dedicated mechanical fixture,
- On the in-line and stand-alone systems, there is also a connection for vacuum and adequate safety precautions for safeguarding the operators,
- Power supplies are provided as options for powered-up testing of he DUT
- Boundary scan test can be added to the platforms as an additional option. Customers may choose the boundary scan tool set that they wish to integrate from a suite of options.
- Also a suite of software tools are provided that serve multiple end objectives some of which are listed below:
- Manipulate board CAD data to generate the test program automatically – provided as an option
- Develop, execute, and debug a test program – provided as standard
- Execute the test sequence during production – provided as standard
- Generate various reports including test coverage and test reports for each individual DUT that passes through – provided as standard
- interface with an automated repair environment – provided as an option
- Option to provide for individual tracking of DUTs by barcode, ,serial number, or other similar method –
For detailed specifications of the measurement unit, please view here
We configure In-Circuit Testers in many different ways. As shown in the above pictures, the testers can be configured as stand alone stations, or as in-line systems that we can install at the end of a surface-mount production lines. Also, more compact versions can be used as table top units. The configuration depends on our customers use-model and we offer flexible solutions to cater for every need.
Boundary Scan Test
Boundary Scan (JTAG) Test has become an essential tool in any modern suite of manufacturing test tools. The great advantage of Boundary Scan is the robustness of test, and low cost, however, developing and debugging boundary scan tests is often more time consuming and challenging than appears at first. Success with Boundary Scan testing depends on a trilateral cooperation between board designers, semiconductor vendors, and test developers. In many organizations, the opportunity to benefit from Boundary Scan testing is lost because these elements are not brought together early in the design cycle.
With new semiconductor devices introduced to the market at a fast pace, there are sometimes issues with the BSDL models (boundary scan building blocks) which prohibit developing effective boundary scan test procedures within the time schedule of the project. Other times, there are oversights – often minor – in the design of the board that prevent effective use of the silicon nails that are available on larger components of the board. Many nets connected to digital BGA devices can be covered for shorts and opens with Boundary Scan test if design for testability rules are observed during the design phase of the product.
Another important and effective way to use Boundary Scan Test is when we integrate boundary scan capabilities with various forms of in-circuit testers. Given the mutually exclusive test coverage tendencies of bed-of-nails test verses boundary scan, in many scenarios, a more comprehensive test coverage can be attained if both techniques are used on the same platform.
In evaluating test requirements, we will analyze your DUTs and offer recommendations to improve test coverage by using design practices that will improve test coverage.