Advanced design and manufacturing technology increasing complexity require rigorous development process to achieve the most stringent quality standards and fuel innovation. These efforts have come together in our new, robust Integrated Platform Development Lifecycle model. The process involves the early planning and architecture of an aligned set of pre-validated elements that are delivered as a complete “design platform” solution to offer optimal performance, the highest quality results, and a superior “out-of-the-box” design experience for devices and boards.
The Vivado® Design Suite along with the Xilinx software development environments (SDx) represent a major advancement in ease of use for Adaptive Computing Accelerator Platform (ACAP) developers. Xilinx development tools accelerate integration, implementation, verification and debug capability, and have been designed to handle exponential growth in device densities reaching 10s of millions of logic cells. In 2019, Xilinx introduced Vitis – Unified software platform for all developers.
Vivado/SDx Quality Initiatives:
Figure 1. Vivado Quality Initiatives.
Vivado™/SDx IP Quality Initiatives:
Figure 2. Vivado IP Quality Initiatives.
Earlier and more stringent testing and verification mitigate the risks that stem from increasing complexity. Testing with higher-level customer designs increased the prerelease discovery and resolution of issues. With more issues identified during development, the impact on customers is minimized and design cycles are accelerated for higher-quality products and an improved user experience.
Figure 3. Earlier and more stringent testing and verification mitigate the risks that stem from increasing complexity. Testing with higher-level customer designs increased the prerelease discovery and resolution of issues. With more issues identified during development, the impact on customers is minimized and design cycles are accelerated for higher-quality products and an improved user experience.
Enhanced Design-for-Reliability (DFR) methodology and guidelines have proven a FIT rate less than 12 at production. Appropriate reliability design rules, budgets and guardbands were established to address post-stress degradations and long-term reliability.
Xilinx reliability methodologies overcame the shrinking reliability margins for the leading process nodes. By leveraging early learning, in-depth tools expertise and machine-learning, Xilinx engineers shortened development processes from months to days, and accommodated the extra iterations required for 28/20/16nm. As a result, Xilinx devices are meeting the stringent requirements of the most reliability-sensitive applications in industrial, automotive, aerospace, and defense industries through:
Figure 1. From 28nm to 16nm, wafer-level reliability exceeds transistor and interconnect market requirements to deliver industry-leading device FIT.
“If you can’t test it, then don’t design it.” Xilinx design engineers place priority on the ability to detect problems quickly and identify root causes that enable solutions. The Xilinx approach starts with Design-for-Test (DFT) methodologies and the New Product Introduction (NPI) process, and extends throughout the complete product life cycle.
Xilinx continuously improves the test methodology of all products from generation to generation through implementing various Design-for-Testability (DFT) methods and tools. These techniques span digital logic, IP, memory elements, I/O boundary scanning, and many other areas. New test methodologies are measured against PPM results from customer returns. It builds quality into the design of world’s most advanced technology and largest All Programmable / Adaptive Computing Accelerator Platform (ACAP) die.
Design methodology focused on quality integration through all phases of design cycle:
|Circuit Under Test||Primary Fault Target and Type||Test Methodology||Test Coverage Metric|
|Degital Logic||Combinational and Sequential Circuits||Single stuck-at faults||Deterministic ATPG, LBIST and fault-graded functional vectors||Overall entire FPGA > 99%, individual IP blocks range from 98% to 99.9%|
|At-speed transition faults||Deterministic transition ATPG or LBIST||80-92% depending on IP block|
|Path delay faults||Path delay ATPG||First 500|
|IP||High-speed I/Os, e.g., SerDes, and BER DDR||BER||PRBS Ioopback (both near end and far end for SerDes)||100% industry-standard testing|
|PRBS Ioopback for DDR, embedded BERT, Tx to Rx internal parallel loopback||100% industry-standard testing|
|PLL||Jitter, frequency||Embedded BIST||100% functional test|
|Mixed-signal IPs||Analog defects (no digital type of defects)||Functional vectors or functional BIST||100% functional test|
|Memory elements||Embedded memory||Cell stuck-at, stuck-open, coupling, transition, address decoder, transient R/W, data retention, and port fault for multiport memory||Mats = algorithm for all port widths: 13n moving inversion algorithm; two-port memory tests; at-speed tests||100% industry-standard testing|
|I/O boundary scan||Open, short, stuck at||Boundary scan IEEE 1149.1 for all I/Os and IEEE 1149.6 for high-speed I/Os||100% functional test|
|Misc. / Other||Temp sensor||Measure on-die temperature||JTAG accessible||100% functional test|
|Voltage sensor||Measure on-die voltage||JTAG accessible||100% functional test|
|Electronic chip ID||Device ID including wafer lot, wafer number, X/Y coordinates||JTAG accessible||100% functional test|
Table 1. Key Manufacturing Tests: These test examples illustrate the test methodology innovation and continuous improvements that are intrinsic parts of the Xilinx engineering culture. Learnings from previous generations and excellent coverage are leveraged to overcome the challenges with newer technology and ultimately enable the release of high-quality Adaptive Computing Accelerator Platforms (ACAPs).
Xilinx Design-for-Manufacturability (DFM) engineering discipline ensures quality, reliability, and time-to-market by focusing on mitigating risks and optimizing operational excellence. It starts with rigorous design of experiments, tests and manufacturing methodologies such as:
These methodologies behind the industry’s first 28nm (28Gb/s) 3D IC heterogeneous devices and now extended at 20nm (33Gb/s) and 16nm (56Gb/s) – Figures 1 and 2 – are fully integrated to meet performance and specifications.
Figure 1. 33Gb/s Eye Diagram in 20nm
Figure 2. 56Gb/s Eye Diagram using PAM-4 in 16nm
Xilinx New Product Introduction (NPI) process was established and refined over the last five generations of Xilinx technology, culminating in our 28/20/16nm products, which include our FPGAs, 3D ICs and SoCs devices. The NPI is a robust and rigorous process with stringent exit criteria targeting the highest quality of Xilinx products in Engineering Silicon (ES) and production release phases. Some NPI activities include:
Figure 1: From first silicon to production material ship, Xilinx has redefined its verification and characterization process to drive early discovery to release with zero errata.
The results are in and have ended all debate. The company embraced a hallmark zero-defect mentality with focus on quality and reliability-which spans across design, process development, assembly, and test-guided by fifth-generation new product introduction (NPI) processes and the most stringent release criteria to date.
The end-result of Xilinx commitment to quality is exhibited with Customer Quality Scorecards, a direct feedback mechanism provided by our customers. With all the challenges related to shrinking process nodes, DFT, DFR and DFM expectations keep increasing to sustain the excellent results, demonstrated by customer-experienced PPM results.
Xilinx Verification & Characterization (V&C) ensures that products operate over the specified voltage and temperature ranges. V&C starts with building in sufficient margin in the design phase, which is then validated during simulation prior to product tape out. Critical circuits are verified using test vehicles. Finally, production-ready product quality is characterized based on the datasheet and Xilinx IP across all process corners, voltage, and temperature (PVT) combinations. The data is used to evaluate product performance against the published datasheet and established production test margins.
Xilinx engineers have proven that they verify, characterize, test, and qualify devices better and faster than anyone else in the industry. At 16nm, the advancements improved data collection, verification, and characterization with:
Figure 1. SSO Data: With package complexity, SSO characterization data validates Xilinx simulation methodologies that contribute to packaging design.
With every product release, Xilinx publishes characterization reports that validate product datasheet specifications and give customers a better understanding of Xilinx methodologies and techniques. The following steps depict the key milestone criteria prior to release of characterization reports and product specifications:
Figure 2. Sample Characterization Report: With every product release, Xilinx publishes characterization reports that validate product datasheet specifications and give customers a better understanding of Xilinx methodologies and techniques.