Memory Testing
Memory TESTING
Vannapha Phommathansy Yi Lan Suhas Shanker Prodduturi Prashant Tripathi Balaji Panda
Agenda 1. Brief overview of Memory 2. Fault type , Fault modeling
3. 5. 6. 7.
Discuss FuncEonal fault and Reduce FF Coupling fault Address decoder fault March test Algorithm
8. Conclusion 9. Q&A
Overview of Memory
ü Memory is the most dense physical structure ü Considering the increase density, memory arrays are more sensiEve to defects
DRAM FLASH Semiconductor memory
SRAM
ROM
CDRAM
Test Eme in Sec VS size n bit
Fault Types
1. Permanent: can’t be model , system is broken and fault exist indefinitely 2. Transient: non permanent cause by environmental condiEon can be fix 3. Intermi\ent: caused by non environmental condiEon, occur randomly.
Fault Modeling
Ø Behavior Ø FuncEonal Ø Logic Gate Ø Electrical Ø Geometrical
² Simplified ² Reduce funcEonal test ² Subset funcEonal test
FuncEonal Memory Model
Reduce funcEonal fault
SAF – Stuck at fault TF – TransiEon fault CF -‐ coupling Fault Address Decoder Fault 1. CF Inversion 2. CF Idempotent 3. Bridging Fault 4. Dynamic fault 5. State Coupling 6. NPSF -‐
Vannapha Phommathansy Yi Lan Suhas Shanker Prodduturi Prashant Tripathi Balaji Panda
Agenda 1. Brief overview of Memory 2. Fault type , Fault modeling
3. 5. 6. 7.
Discuss FuncEonal fault and Reduce FF Coupling fault Address decoder fault March test Algorithm
8. Conclusion 9. Q&A
Overview of Memory
ü Memory is the most dense physical structure ü Considering the increase density, memory arrays are more sensiEve to defects
DRAM FLASH Semiconductor memory
SRAM
ROM
CDRAM
Test Eme in Sec VS size n bit
Fault Types
1. Permanent: can’t be model , system is broken and fault exist indefinitely 2. Transient: non permanent cause by environmental condiEon can be fix 3. Intermi\ent: caused by non environmental condiEon, occur randomly.
Fault Modeling
Ø Behavior Ø FuncEonal Ø Logic Gate Ø Electrical Ø Geometrical
² Simplified ² Reduce funcEonal test ² Subset funcEonal test
FuncEonal Memory Model
Reduce funcEonal fault
SAF – Stuck at fault TF – TransiEon fault CF -‐ coupling Fault Address Decoder Fault 1. CF Inversion 2. CF Idempotent 3. Bridging Fault 4. Dynamic fault 5. State Coupling 6. NPSF -‐