SUNBAR - A Universal Boundary Scan Architecture for a Sea-of-Gates Semi-Custom Environment

Abstract

A concept for a Standardized Universal Boundary Scan Architecture for semi-custom sea-of-gates ASICs (SUNBAR) is presented that complies with the IEEE 1149.1 standard and is extensible in a flexible way to control and observe a built-in (self) test of complex circuits. Using a fixed, extensible part with basic boundary scan functions integrated as a full custom circuitry on the master, and a part with enhanced functions placed on the semi-custom core of the chip, the architecture combines high flexibility with low area consumption. Besides its boundary scan functionality, SUNBAR can be used as a front-end for structured design-for-testability measures like multiple scan paths, macro testing via hierarchical test controllers, BIST using PRPG/PSA circuitry, etc. SUNBAR supports all testable designs on the IMS Gate Forest, a 1.2¿m sea-of-gates array.