In today’s competitive and rapidly changing electronics market, the speed and effectiveness of product testing have a significant impact on your bottom line and time-to-market. This booklet contains the background information on boundary-scan, one of the most effective methodologies available today for testing and in-system programming.

Managers and designers will find the facts needed to help them reach an informed decision on whether to include boundary-scan in their test and/or device programming strategy. The choice of such a strategy is crucial to overall product success, involving many departments within the enterprise in the planning and execution. Moreover, these departments can benefit directly from the right choice: designers, prototype providers, factory personnel, test engineers, and the repair department all have a stake in and benefit from the test strategy and programming method that are adopted.

If any of the following situations apply to you, now may be the right time to consider using boundary-scan:

Existing test methods, such as functional testing and in-circuit testing (ICT) which have worked well in the past, are losing their effectiveness, due to the impact of new technologies such as ball-grid arrays (BGAs) on electrical access to your circuit boards

• You need to make Design-For-Testability (DFT) an essential part of your design process, along with the need for a reliable method of knowing the test coverage and how to improve it
• You need to reduce the overall cost of testing without compromising product quality
• You have an unacceptable number of boards in your “bone-pile”— boards that fail functional test but can’t be diagnosed and thus remain unrepaired
• You’re still using off-line device programming methods but want to save costs, increase quality, and create more flexibility in the factory and in the field
• You’re under pressure to shorten the time-to-market for new products

Many of the IC devices in use on your products may already support boundary-scan (or JTAG as some IC vendors call it), whether you’re using it or not. For example, the PowerPCs of IBM and Motorola, programmable logic devices from Altera, Xilinx, Lattice and STMicroelectronics, digital signal processors (DSPs) from Texas Instruments, wireless processors from Qualcomm, most application specific ICs (ASICs), and many others fully comply with IEEE 1149.1.

So, it’s quite possible that you can easily tap into the power of boundary-scan to improve board testability, dismantle the bone-pile, speed up board design and prototype debug, and even perform in-system programming of flash memory and programmable logic devices via the boundary-scan chain. Regardless of which part of the product life cycle you’re involved in, this booklet can help you learn the hows of boundary-scan: how it works, how you can benefit, and how to get started.