Shared Boundary Scan Elements for I/O Pin Testing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing integrated circuit testing methods require dedicated boundary scan elements for each I/O pin, leading to increased circuit area and complexity, especially for I/O pins without dedicated boundary scan elements, which can result in longer testing times and increased complexity.
Innovation Solution
The proposed solution involves sharing boundary scan elements among sets of I/O pins, using test circuitry and a test controller to drive binary test signals through the shared boundary scan elements to both I/O devices with and without dedicated boundary scan elements, thereby allowing for boundary scan testing of all I/O devices within a single test routine.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If dedicated boundary scan elements are provided for each I/O pin, then testing coverage is improved, but circuit area and complexity increase
Solution Approach 1:
The boundary scan elements are designed to serve multiple I/O pins rather than being dedicated to a single pin. The test controller selectively couples boundary scan elements to different I/O pins during different test operations, allowing one boundary scan element to perform testing functions for multiple pins sequentially, thereby reducing the total number of boundary scan elements required while maintaining comprehensive testing coverage
Solution Approach 2:
The system employs dynamic reconfiguration of the test circuitry through selective coupling mechanisms controlled by the test controller. The boundary scan elements can be dynamically connected to different I/O pins based on which pin requires testing at any given moment, transforming a static one-to-one mapping into a dynamic many-to-one relationship that optimizes resource utilization
2Reliability
If dedicated boundary scan elements are provided for each I/O pin, then testing completeness is improved, but testing time increases
Solution Approach 1:
Multiple testing functions for different I/O pins are merged into a unified test routine. The test controller orchestrates the selective coupling of boundary scan elements to different I/O pins within a single integrated test sequence, combining what would traditionally require separate test operations into one cohesive testing process that maintains completeness while reducing overall testing time
Solution Approach 2:
The test controller maintains continuous testing operations by seamlessly transitioning the boundary scan elements from one I/O pin to another without interrupting the overall test flow. This continuous reconfiguration allows the testing process to proceed without idle time between tests on different pins, keeping the testing action productive throughout the entire test cycle
3Adaptability or versatility
If more boundary scan elements are used, then testing capability is improved, but resource requirements increase
Solution Approach 1:
Boundary scan elements are designed with universal functionality to test multiple types of I/O pins through selective coupling. Rather than requiring specialized boundary scan elements for each pin type, the system uses a smaller set of versatile boundary scan elements that can be configured to test any I/O pin in the array, thereby maintaining high testing capability while reducing the quantity of boundary scan elements required
Data Source
AI summary
Methods and apparatus for boundary scan. In one example, a circuit includes at least one first input/output (I/O) device, at least one boundary scan element coupled to the at least one first I/O device, and at least one second I/O device coupled to the at least one boundary scan element. The circuit may further include a test controller coupled to the at least one boundary scan element and configured to control the at least one boundary scan element to drive the at least one first I/O device and the at least one second I/O device with a binary test signal.