This document is the third of the Industry Council white papers dealing with System Level Electrostatic Discharge (ESD). The previous two white papers addressing system level ESD are the Industry Council’s WP3 Part I and WP3 Part II.
In WP3 Part I, the misconceptions common in the understanding of system level ESD between supplier and original equipment manufacturer (OEM) were identified, and a novel ESD component / system co-design approach called system efficient ESD design (SEED) was described. The SEED approach is a comprehensive ESD design strategy for system interfaces to prevent hard (permanent) failures. In WP3 Part II this comprehensive analysis of system ESD understanding to categorize all known system ESD failure types was expanded, and described new detection techniques, models, and improvements in design for system robustness. WP 3 Part II also expands this SEED co-design approach to include additional hard / soft failure cases internal to the system. This third document on system level ESD takes this further while focusing on system testing of ports and the shortcomings of air discharge testing.
Part A of the document highlights the need of a consistent and standardized specification of IO Port contact discharge which is widely used in industry. This is supported by real world discharge scenarios like cable discharge. A well specified testing procedure and the related target levels for IO port direct pin injection are the base for a SEED simulation and co-design approach which can commonly be executed by IC suppliers and system customers.
Part B addresses air discharge testing, which is most relevant for field fails, while its specification in IEC 61000-4-2 and its practical application suffers from both missing repeatability and reproducibility. In the first part, the arguments of maintaining air discharge as a relevant, mandatory test method are explained. Various scenarios leading to real world discharge events which correlate to IEC 61000-4-2 testing are analyzed in more detail. They can lead to soft and hard fails reproducible by system ESD testing. Secondly, in this document new considerations to better calibrate the air discharge test and reliably perform a repeatable air discharge test are given.