Diagnostic Data Compression Techniques for Embedded Memories with Built-In Self-Test

A system-on-chip (SOC) usually consists of many memory cores with different sizes and functionality, and they typically represent a significant portion of the SOC and therefore dominate its yield. Diagnostics for yield enhancement of the memory cores thus is a very important issue. In this paper we present two data compression techniques that can be used to speed up the transmission of diagnostic data from the embedded RAM built-in self-test (BIST) circuit that has diagnostic support to the external tester. The proposed syndrome-accumulation approach compresses the faulty-cell address and March syndrome to about 28% of the original size on average under the March-17N diagnostic test algorithm. The key component of the compressor is a novel syndrome-accumulation circuit, which can be realized by a content-addressable memory. Experimental results show that the area overhead is about 0.9% for a 1Mb SRAM with 164 faults. A tree-based compression technique for word-oriented memories is also presented. By using a simplified Huffman coding scheme and partitioning each 256-bit Hamming syndrome into fixed-size symbols, the average compression ratio (size of original data to that of compressed data) is about 10, assuming 16-bit symbols. Also, the additional hardware to implement the tree-based compressor is very small. The proposed compression techniques effectively reduce the memory diagnosis time as well as the tester storage requirement.

[1]  Ad J. van de Goor,et al.  Using March Tests to Test SRAMs , 1993, IEEE Des. Test Comput..

[2]  Frans P. M. Beenker,et al.  A realistic fault model and test algorithms for static random access memories , 1990, IEEE Trans. Comput. Aided Des. Integr. Circuits Syst..

[3]  Jin-Fu Li,et al.  Using syndrome compression for memory built-in self-diagnosis , 2001, 2001 International Symposium on VLSI Technology, Systems, and Applications. Proceedings of Technical Papers (Cat. No.01TH8517).

[4]  Krishnendu Chakrabarty,et al.  System-on-a-chip test-data compression and decompressionarchitectures based on Golomb codes , 2001, IEEE Trans. Comput. Aided Des. Integr. Circuits Syst..

[5]  Janak H. Patel,et al.  Diagnosis and Repair of Memory with Coupling Faults , 1989, IEEE Trans. Computers.

[6]  Subramanian S. Iyer,et al.  Embedded DRAM technology: opportunities and challenges , 1999 .

[7]  Jin-Fu Li,et al.  Memory fault diagnosis by syndrome compression , 2001, Proceedings Design, Automation and Test in Europe. Conference and Exhibition 2001.

[8]  Bruce F. Cockburn,et al.  An optimal march test for locating faults in DRAMs , 1993, Records of the 1993 IEEE International Workshop on Memory Testing.

[9]  Cheng-Wen Wu,et al.  Error catch and analysis for semiconductor memories using March tests , 2000, IEEE/ACM International Conference on Computer Aided Design. ICCAD - 2000. IEEE/ACM Digest of Technical Papers (Cat. No.00CH37140).

[10]  Craig Hunter,et al.  Integrated diagnostics for embedded memory built-in self test on PowerPC/sup TM/ devices , 1997, Proceedings International Conference on Computer Design VLSI in Computers and Processors.

[11]  Dat Tran,et al.  The testability features of the 3rd generation ColdFire/sup (R)/ family of microprocessors , 1999, International Test Conference 1999. Proceedings (IEEE Cat. No.99CH37034).

[12]  A.J. van de Goor,et al.  RAM diagnostic tests , 1996, IEEE International Workshop on Memory Technology, Design and Testing,.

[13]  Elizabeth M. Rudnick,et al.  Diagnostic testing of embedded memories using BIST , 2000, DATE '00.

[14]  Jin-Fu Li,et al.  A built-in self-test and self-diagnosis scheme for embedded SRAM , 2000, Proceedings of the Ninth Asian Test Symposium.

[15]  Mark Rich A Method of Flexible Catch RAM Display for Memory Testing , 1986, ITC.

[16]  David A. Huffman,et al.  A method for the construction of minimum-redundancy codes , 1952, Proceedings of the IRE.

[17]  Jin-Fu Li,et al.  March-based RAM diagnosis algorithms for stuck-at and coupling faults , 2001, Proceedings International Test Conference 2001 (Cat. No.01CH37260).

[18]  Cheng-Wen Wu,et al.  RAMSES: a fast memory fault simulator , 1999, Proceedings 1999 IEEE International Symposium on Defect and Fault Tolerance in VLSI Systems (EFT'99).

[19]  Nur A. Touba,et al.  Test vector decompression via cyclical scan chains and its application to testing core-based designs , 1998, Proceedings International Test Conference 1998 (IEEE Cat. No.98CH36270).

[20]  Michael J. Flynn,et al.  An area model for on-chip memories and its application , 1991 .

[21]  Alfredo Benso,et al.  A programmable BIST architecture for clusters of multiple-port SRAMs , 2000, Proceedings International Test Conference 2000 (IEEE Cat. No.00CH37159).

[22]  G.G. Langdon,et al.  Data compression , 1988, IEEE Potentials.

[23]  Robert Gage,et al.  Hardware compression speeds on bitmap fail display , 1997, Proceedings International Test Conference 1997.

[24]  Cheng-Wen Wu,et al.  Testing content-addressable memories using functional fault modelsand march-like algorithms , 2000, IEEE Trans. Comput. Aided Des. Integr. Circuits Syst..

[25]  Chih-Tsun Huang,et al.  Core-based system-on-chip testing: Challenges and opportunities , 2001 .

[26]  Wojciech Maly,et al.  Enabling embedded memory diagnosis via test response compression , 2001, Proceedings 19th IEEE VLSI Test Symposium. VTS 2001.

[27]  M. Wada,et al.  A configurable DRAM macro design for 2112 derivative organizations to be synthesized using a memory generator , 1998, 1998 IEEE International Solid-State Circuits Conference. Digest of Technical Papers, ISSCC. First Edition (Cat. No.98CH36156).

[28]  J Van De GoorAd Using March Tests to Test SRAMs , 1993 .