XJTAG Speeds Debug and Test of Complex BGA Circuits for Prism

Prism Electronics, a UK-based contract electronics manufacturer (CEM), has selected the XJTAG boundary scan development system to speed up the process of debugging and testing highly complex printed circuit boards featuring high pin count ball grid array (BGA) devices such as field programmable gate arrays (FPGAs).

The XJTAG system has been implemented at Prism’s 6,500 square foot manufacturing facility in St Ives, England, where it has led to significantly improved production test coverage – up to 98% for certain boards – and it is also being used extensively for new product introductions and prototype verification.

The XJTAG system meets the growing market need for a cost-effective solution for testing printed circuit boards populated with BGA and chip scale devices. Such devices cannot be effectively tested by traditional methods such as flying probes, logic analyzers, oscilloscopes and X-ray systems.

“The XJTAG system offers incredible value, power, performance and flexibility all within one self-contained suite of development tools,” said David Dickin, business development director at Prism. “Unlike other boundary scan products we considered, XJTAG is simple and easy to use, test scripts are written in a C-like programming language familiar to test development engineers, and these scripts are device-centric making them re-usable throughout the product lifecycle.”

Prism offers a wide range of electronics manufacturing services covering the complete product lifecycle, from concept through design, manufacture, test and distribution, to end-of-life. Prism focuses on the production of modest volumes of complex products and prides itself in creating cost-effective individual service and supply chain solutions for customers in a wide range of markets including medical, military, scientific, communications, IT and industrial electronics.

“Boundary scan is now a must-have tool for contract manufacturers that assemble high value, high complexity boards with BGA devices, as these cannot be tested by traditional methods,” added Richard Walton, technical director at Prism.

“It’s no longer sufficient to test that a BGA device has been soldered correctly, we now need to prove that it is electrically operational too,” continued Richard Walton. “With XJTAG, we can gain access to the boundary scan chain and get an interactive graphical view of all the device pins, and we can read or write pins and busses with a single click to test that they are free from opens and shorts.”

XJTAG offers CEMs a multitude of significant and quantifiable benefits. It improves the speed and accuracy of fault diagnosis, achieves high test coverage, boosts production yields and reduces lifecycle costs. In addition, as product development cycles shorten and board re-spins become more frequent, it can also replace costly in-circuit test fixtures.

“XJTAG is one of the tools in our test armoury which increasingly overlaps and outperforms other test methods, extending beyond the detection of process faults to the true detection of faulty devices,” added Richard Walton. “On one customer design, which contains five boundary scan enabled devices including a ColdFire CPU, three Xilinx FPGAs and an Ethernet controller, we have got test coverage up consistently to around the 95-98% mark by using XJTAG – this has helped us to significantly improve our yields.”

The XJTAG development system is an ‘out-of-the-box’ solution for debugging and testing complex printed circuit boards populated with boundary scan-enabled and cluster devices including BGA and chip scale devices, SDRAMs, Ethernet controllers, video interfaces, Flash memories, FPGAs, microprocessors and many other devices. It can migrate seamlessly through the product life cycle from early design and prototyping through to production, field support and repair.

XJTAG enables circuit designers to cut the cost and shorten the development cycle by facilitating early test development, early design validation of CAD netlists, fast generation of highly functional tests and test re-use across circuits that utilise the same devices. XJTAG also enables In-System Programming of FPGAs, CPLDs (Complex Programmable Logic Devices) and Flash memories. Pricing for the XJTAG system ranges from £3,500 (€5,075) to £9,000 (€13,050).

For more information about the XJTAG Development System, please contact XJTAG, The Irwin Centre, Scotland Road, Dry Drayton, Cambridge CB23 8AR, England. Telephone +44 (0) 1954 213888, facsimile +44 (0) 1954 211565 or email info@xjtag.com. Alternatively visit www.xjtag.com.

Visit XJTAG at Electronica (Hall A1/Stand 259) November 14-17, New Munich Trade Fair, Germany.

About Prism Electronics
Prism Electronics offers a wide range of electronics manufacturing services covering the complete product life-cycle, from concept through design, manufacture, test and distribution, to end-of-life. Prism focuses on the production of modest volumes of complex products and prides itself in creating cost-effective individual service and supply chain solutions for customers in a wide range of markets including medical, military, scientific, communications, IT and industrial electronics. The company won the Most Improved Plant category at the national 2005 Best Factory Awards and has recently invested over £100,000 preparing its manufacturing operations to comply with new European legislation on lead-free manufacturing which came into force in July 2006.

About XJTAG
XJTAG is a specialist design and test tool developer. Its JTAG (Joint Test Action Group) development system offers a competitive solution for designers and developers of electronic circuits. Utilising XJTAG allows the circuit development and prototyping process to be shortened significantly by facilitating early test development, early design validation, fast development of functional tests and test re-use across circuits that use the same devices. The company is based in the UK at The Irwin Centre, Dry Drayton, Cambridge. XJTAG is part of the Cambridge Technology Group.

What is JTAG?
Advances in silicon design, such as increasing device density and, more recently, ball grid array (BGA) and chip scale packaging, have reduced the efficacy of traditional electronic circuit testing methods. In order to overcome these problems and others; some of the world’s leading silicon manufacturers combined to form the Joint Test Action Group (JTAG). The findings of this group were used as the basis for the Institute of Electrical and Electronic Engineers (IEEE) standard 1149.1: Standard Test Access Port and Boundary Scan Architecture and subsequently the standard became known as JTAG.