Self-Test on a Read-Only Memory
Original Publication Date: 1985-Feb-01
Included in the Prior Art Database: 2005-Feb-18
Self-test by signature analysis is an economical way of dealing with read-only memory (ROM) products. The usual way is to build the personalization mask of a ROM with the bit pattern provided by the user and to keep this bit pattern and retrieve it several weeks later to test the parts on a very expensive tester before delivering the parts to the user. All these operations can be avoided by using the signature analysis. A linear feed-back shift register (LFSR) can be used to compress the test data. The result of the compression being stored in the last memory word for example. Proposed Implementation A linear feedback shift register is provided at the memory input to generate a pseudo random address sequence, and a linear feed-back shift register is provided at the memory output to analyze the signature.