Since ddr price increases, especially the fluctuating ddr5 ram price in sri lanka, 16gb ddr5 ram price in bd, there are lots DDR brands in the market. How to ensure the the product quality of the industrial switch and the mini olt? That requires us to analyze detail from the product principle.
1. ddr price increases: Wafer testing grading system
1.1The original factory, Every chip on the wafer is tested with extremely harsh and rigorous tests. The core of the complete test process:
1.1.1 CP test: full function and parameter probe test of wafer;
1.1.2 Thermal testing: Function verification of all temperature nodes at low temperature, normal temperature and high temperature;
1.1.3 Voltage deviation test: Parameter consistency screening under the nominal voltage ± allowable deviation range;
1.1.4 AC/DC parameter precision measurement: time sequence, leakage, drive ability, etc;
1.1.5 High-speed classification: Signal integrity verification and speed classification under multiple frequency levels;
1.1.6 High temperature aging test: high temperature high voltage dynamic aging, elimination of early failure;
1.1.7 System-level final test: Platform compatibility, data retention capability and final performance verification.
1.2 Ddr price increases: ETT+ (enhanced eTT)
The original factory has not fully tested the eTT grade wafer that is screened by the whole temperature aging. Other test subjects need to go to a third party sealing factory to do supplementary screening, the main testing selection include:
1.2.1 Functional verification at the target frequency and rate classification.
1.2.2 Stability screening within a specific voltage window.
1.2.3 Functional testing under a limited temperature gradient (Non-fully three-dimensional temperature).
1.2.4 Short-term stress testing based on ATE, replacing the original factory-level Burn-in aging.
1.3 Ddr price increases: eTT(Effectively Tested, standard eTT white sheet)
The term "eTT" literally translates to "after effective electrical testing", but in reality, it refers to "only conducting the most basic power-on test" of the particles, which directly affects the stability related to 16gb ddr5 ram price in bd and ddr5 ram price in sri lanka. After the chips are fabricated, the original factory will package some "semi-finished wafers" that have not undergone complete and strict testing and sell them to downstream packaging factories. Alternatively, the downstream manufacturers purchase the wafers and only perform basic tests that can "light up", but without strict screening.
2.The differences between wafers
Dimension | eTT Bare Die | ETT+ | Original Major Tested Die |
Test Completeness | Only basic connectivity test at room temperature; no coverage of functional vectors, speed binning and parameter screening | Enhanced third-party screening: target frequency function verification, limited temperature sampling test and short-term stress test; does not cover full temperature, full voltage and complete vectors | Full JEDEC standard process implemented by the manufacturer: CP test, full functional vectors, 3-temperature test, voltage stress test, high-speed binning and system-level final test |
Reliability Assurance | No aging or reliability screening; extremely high risk of early failure | No manufacturer-level high-temperature & high-voltage dynamic aging; relatively high probability of early failure | Undergoes strict Burn-in aging to effectively eliminate early failures, with long-term reliability data and ultra-low factory failure rate |
Parameter Consistency | No binning; AC/DC parameters, timing and power consumption have extremely large dispersion, fully dependent on batch luck | Binned only based on partial performance windows; certain dispersion still exists in timing, leakage current and other parameters | Precisely measured and strictly binned for AC/DC parameters; high consistency of all electrical indicators with predictable performance |
Temperature Adaptability | Verified only at room temperature; prone to data errors, crash or failure under high or low temperature | Generally verified within a narrow temperature range; stability under extreme temperatures is not guaranteed | Full functional testing from -40°C to 95°C (or wider range) to guarantee qualified performance across the full temperature spectrum |
Traceability | No original manufacturer marks or batch codes; usually blank dies or ground dies, non-traceable | No factory records or complete wafer trace codes from the original manufacturer, only internal third-party marks | Complete original manufacturer trace codes, traceable back to wafer lot, test equipment station, binning data and full factory history |
3.Why are there eTT white films?
In the production of wafer, some factors of high yield edge, production line capacity limitation or market strategy are not arranged for complete test and aging wafer. The original factory made it out of the "semi-finished product" state, stripped off the cost of the follow-up test, and quickly recover founds.
Purchase of original materials at the downstream stage: a third party package factory or trader buys a whole wafer at a very low cost, and only implements the most basic test of the electricity, after conducting the most basic test of ensuring power supply immediately after production, the product was released for distribution, resulting in the eTT white version.. This is purely "bottom-line" cost competition.
4. The emergence of ETT+
Part of the factory or distributor, who is dissatisfied with the high abandonment risk and performance of ett. So they conducted secondary enhancement test and classification for the purchased ett wafer. Through screening, we select the particles with performance close to the original factory standards from eTT, and sell them at a price lower than that of the original positive film but higher than that of eTT. This is precisely targeted at "non-critical applications that require certain quality but prioritize cost".
5. The advantages of Rayin Technology
As a manufacturer of independent R&D of industrial communication equipment, Rayin Technology can provide free technical evaluation service, help you match the function of the project. For complete product plan and technical white paper, welcome to the website: www.szrayin.com.
