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| Ramtron has been aware of the existence of counterfeit F-RAM products. Ramtron has investigated the situation and has detailed its findings below. To avoid the possibility of obtaining counterfeit Ramtron products, always buy Ramtron products from Ramtron or one of its authorized product representatives or distributors, which are identified in the sales section of this web site. If you believe that you are currently in possession of counterfeit Ramtron products, please contact us immediately. |
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| In the cases detailed below the failure of the counterfeit devices was easy to detect due to the different addressing schemes between a genuine Ramtron FM25160 device and the substituted device in the counterfeit packaging. Although Ramtron has not discovered any other counterfeit F-RAM devices, it is important to note that some of Ramtron's devices have similar addressing schemes to EEPROM devices and the only way to detect a failure may be via a write speed or write endurance failure in the field. This issue underscores the importance of not buying from chip brokers or suspicious sources and only buying genuine Ramtron devices from an authorized Ramtron source. |
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| Background |
| Ten "FM25160-S" parts from Lot B082545, date code RIC0428, were returned by a customer for failure analysis. The customer noticed that the package marking was different on this lot than for other lots that operate properly. A second set of four parts were subsequently returned to Ramtron for confirmation of the same problem. |
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| Root Cause Analysis |
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| Counterfeit Ramtron devices containing ST Microelectronics EEPROM die |
| The package material from the first set of 10 parts was chemically removed to expose the die, and the die inside the package was an ST Microelectronics (ST) M95160W-S, which corresponds to an EEPROM offering that is similar to Ramtron's F-RAM. Use of an ST die inside Ramtron packaging is not the practice of Ramtron or any of Ramtron's assembly subcontractors. The picture below shows the counterfeit Ramtron part and the non-ramtron die that was in the package. |
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| This proves the subject part counterfeit. The ST EEPROM die requires different addressing than the Ramtron FM25160. The Ramtron FM25160 uses a three byte write, and the M95160W uses a four byte write; the difference being one byte addressing vs. two byte addressing (please see diagrams below). The functional differences in addressing schemes between the ST device and Ramtron's device explains why the counterfeit devices would fail to operate properly in the system. |
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| The following detail clarifies the addressing differences between the ST and genuine Ramtron devices. |
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| STM's Addressing |
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| Ramtron's Addressing (click image to download AN-301 in PDF format) |
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| Packaging description |
| The ten returned "FM25160" parts from Lot B082545, date code RIC0428, were counterfeit parts provided in this packaging: |
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| Label on counterfeit reel: |
| Note the small a in RaMTRON. This is not standard Ramtron labeling practice. Note the misspelled word origin as ORION. |
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| Bottom view: |
| Left-hand part is counterfeit. Right-hand part is genuine. |
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| Top view: |
| Left-hand part is genuine. Right-hand part is counterfeit. |
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| Counterfeit Ramtron devices containing Atmel EEPROM die |
| The package material from the second set of four parts was removed and an Atmel AT19345 die was found. Please note that the counterfeit packaging containing the ST and Atmel die bears similar lot and date codes. |
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| Conclusion |
| If you believe that you are currently in possession of counterfeit Ramtron products, please contact us immediately. |
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