On-Chip Bus Validation Circuitry for At-Speed Electrical Testing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional bus validation tools are inadequate for at-speed electrical validation, often requiring external hardware and being unable to recreate complex conditions like inter-symbol interference, which hinders rigorous testing and diagnosis of bus connections.
Innovation Solution
An automated on-chip tool that facilitates electrical validation of buses at-speed, independent of bus protocols, using dedicated circuitry to generate and check test patterns, allowing for end-to-end testing of bus paths without external hardware, and enabling the simulation of conditions like crosstalk and saturated bus traffic.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional bus validation tools are used, then basic error detection may be achieved, but at-speed electrical validation and rigorous testing cannot be performed
Solution Approach 1:
The bus validation system is integrated directly into the chip, allowing the chip to validate its own bus connections without external equipment. The validation logic and test pattern generators are built-in, enabling the system to perform self-validation at operating speeds, thus achieving both high reliability and high productivity.
Solution Approach 2:
Test patterns and validation logic are pre-configured within the chip architecture, allowing validation to occur automatically during normal operation or designated test cycles. This preliminary preparation enables at-speed validation without requiring external setup or slow external testing equipment.
2Measurement precision
If external hardware like oscilloscopes or protocol analyzers is used, then physical bus connections can be monitored, but the process becomes increasingly difficult with higher chip densities and smaller trace sizes
Solution Approach 1:
Instead of requiring external probes to physically attach to shrinking bus traces, the validation functionality is integrated into the chip itself. This eliminates the need for physical attachments to external hardware, making the process easy to operate regardless of chip density or trace size.
Solution Approach 2:
The validation functionality is extracted from external hardware and embedded directly into the chip architecture. This removes the dependency on external probing equipment and its associated difficulties with high-density interconnects.
3Difficulty of detecting and measuring
If conventional static validation tools are used, then basic circuit faults can be detected, but at-speed electrical problems and inter-symbol interference cannot be evaluated
Solution Approach 1:
The validation system operates dynamically at the actual bus operating speed, allowing detection of speed-dependent issues like inter-symbol interference and signal integrity problems that only manifest at high frequencies. The integrated validation logic synchronizes with the bus clock, enabling real-time detection of timing and electrical issues.
Solution Approach 2:
The system validates the bus under actual operating parameters including high-frequency signals and real bus loading conditions. By changing from static DC validation to dynamic AC validation at operating speeds, the system can detect electrical problems and inter-symbol interference that are invisible to conventional static tools.
4Adaptability or versatility
If integrated circuits must be substantially complete before bus validation, then protocol-dependent validation may occur, but chip and bus development become tightly coupled in serial development
Solution Approach 1:
The validation functionality is segmented into independent modules that can be activated selectively. The bus validation logic can operate independently of the main chip functionality, allowing validation to proceed in parallel with chip development without requiring the entire chip to be complete.
Solution Approach 2:
The validation infrastructure is built into the chip architecture in advance, allowing validation activities to begin early in the development process. This preliminary preparation enables parallel development of chip and bus validation, eliminating the need for serial development where bus validation must wait for chip completion.
Data Source
AI summary
Systems, methodologies, media, and other embodiments associated with validating a bus are described. One exemplary system embodiment includes an integrated circuit operably connectable to a bus, the bus being connectable to an external device configured to drive one or more electrical signals onto the bus. The integrated circuit may comprise a first logic configured to receive a test sequence of electrical signals from the bus, a second logic configured to produce a check sequence of electrical signals related to the test sequence of electrical signals, and a compare logic operably connected to the first logic and the second logic. The compare logic may be configured to determine whether the bus is correctly transmitting data based, at least in part, on comparing the test sequence and the check sequence.