JTAG-based vector and chain management for system test

Abstract

We present an embedded boundary-scan test vector management solution that ensures the correct version of test vectors is applied to the Unit Under Test (UUT). This new vector management approach leverages the system-level boundary-scan multi-drop architecture employed in some high availability electronic systems. Compared to previous methods that do not use system-level boundary-scan resources for vector management, this new approach ensures that the correct boundary-scan vectors are retrieved from the UUT without affecting its operation and requires minimal UUT functionality to execute. The performance and effectiveness of this technique is shown using an actual design example that has been realized in a new product.

Reusable, Low-cost, and Flexible Multidrop System JTAG Architecture

“…Hence, it is desirable to have a system JTAG architecture reusable across different product designs with the flexibility of combining JTAG devices for different JTAG operations. Commercial JTAG multidrop devices (e.g., [1]- [4]) can be used to achieve the above goals (e.g., [5] and [6]). However, the costs of these devices are usually not cheap (about $5-$8 per device, multiple devices may be needed).…”