Sometimes ESD specifications are so hard to meet, you conclude they must be physically impossible. Sofics has helped many customers facing this predicament.
For example, a customer had to guarantee on-chip ESD protection of 8kV according to the IEC 61000-4-2 standard for an analog switch application. No impedance in the signal path was allowed, the capacitive load budget was very small, the total IC size was limited to a specific package – leaving no significant silicon area to add –and the ESD design window was almost non-existent.
To make the situation more uncertain, the process was custom-tailored and thus uncharacterized and unknown to both Sofics and the customer. And the market needed the IC immediately, without delay.
Sofics created a dedicated test chip to extract the ESD design window, characterize the process and the device’s ESD performance, and develop novel solutions for the challenge at hand. The first product implementations were being designed and manufactured at the same time, with a guarantee of normal operational performance and high (to be measured) ESD robustness.
After first silicon the product implementations passed their performance specifications, but corner analysis indicated a risk of failures in mass production. Using our dedicated test structures, we were able to devise adjustments to build in safety margins for commercial fabrication. A whole family of analog switch products using the Sofics custom developed solutions is on the market today.
Sofics has supported many other IC designers to achieve high ESD requirements. A few examples:
|1||6kV HBM – Smartcard application||130nm|
|2||6kV HBM – TCON (LCD panel)||180nm|
|3||8kV HBM – HDMI||130nm|
|4||8kV IEC 61000-4-2 – USB 2.0||350nm|
|5||8kV IEC 61000-4-2 – Analog Switch||350nm|
|6||8kV IEC 61000-4-2 – HDMI TX + Rx||130nm|
|7||8kV IEC 61000-4-2 – battery management||0.6um|
Need more information? Sofics has published a number of papers related to these applications
- On-Chip ESD Protection Achieving 8kV HBM Without Compromising the 3.4Gbps HDMI Interface
- On-Chip ESD Protection with Improved High Holding Current SCR (HHISCR) Achieving IEC 8kV Contact System Level