Welcome
Welcome to the CMD ESD Design Resource Center, an "Extreme ESD" forum for informing and educating digital consumer, mobile and computing equipment providers about the fundamental changes taking place in electrostatic discharge (ESD) protection. The content on this site is intended to eliminate confusion about ESD protection standards and architectures, and allow you to confidently take the next step toward designing more reliable systems.
The Changing ESD Landscape
Two fundamental changes are happening today that impact ESD protection at the system design level. First, systems are becoming more prone to ESD damage, as ICs have become more susceptible to ESD damage. ESD devices that were adequate in previous generations are no longer providing enough protection for these new ICs. Simultaneously, I/O ports are moving to much higher data rates, requiring a stronger focus on signal integrity. With traditional architectures, it is often necessary to make a tradeoff between the level of ESD protection and the signal integrity. Clearly, a new approach to ESD protection is required so that reliable ESD protection and excellent signal integrity can be achieved without compromise.
Why do Traditional ESD Architectures Fail to Provide Suitable Protection?
There are three primary changes happening that are causing increasing ESD susceptibility to end systems:
- Smaller IC Manufacturing Geometries - as manufacturing geometries for today's most advanced ASICs decrease to 90 nm and less, the voltage and current levels that can cause ESD related failures for these devices also decrease. The increasing adoption of high speed data interfaces adds to the complexity of maintaining a high level of signal integrity while ensuring robust ESD protection. More robust ESD protection typically means higher levels of capacitance, which negatively impacts signal integrity and forces designers to compromise on one or the other.
- A Reduction in On Chip Protection - increased susceptibility to ESD damage has been widely publicized as the Industry Council on ESD Target Specifications recently announced a move to reduce the standard level of on-chip ESD protection, making external ESD protection circuits even more critical for adequate system reliability.
- The Changing Application Environment - ESD strikes are becoming more common with the proliferation of laptops, cell phones, MP3 players, digital cameras, and other hand-held mobile devices, which are used in uncontrolled environments (i.e., no wrist-grounding straps or conductive and grounded table surfaces). In these environments, people touch I/O connector pins while connecting and disconnecting cables. A portable device can also build up a charge during normal usage and discharge that energy when connected to another device, such as a computer or a TV.
With traditional ESD architectures, an inverse relationship exists between robust ESD protection and good signal integrity. More robust ESD protection has typically meant higher levels of capacitance, which, in turn, negatively impacts signal integrity forcing designers to carefully balance ESD protection with signal integrity. With the adoption of high speed serial data interfaces and the move to smaller IC geometries, this delicate balance has become increasingly difficult to maintain. Traditional ESD architectures fail to provide suitable protection because they were not designed to protect the increasing levels of susceptibility of these new devices.
Which ESD Devices Provide the Greatest Protection?
Determining which ESD protection device provides the optimal solution is increasingly difficult. Many designers do not know which factors are most important when choosing an ESD device. Often, the answers either are not provided or obvious in many ESD protection datasheets. There is also confusion around interpretation of industry standards, as well as what constitute adequate protection and acceptable testing criteria. Today's designer must also pay considerable attention to voltage level (clamping voltage) and how much current (residual current) will be seen by the ASIC. While low capacitance for signal integrity is certainly important, other crucial signal integrity considerations must be made in regards to layout, capacitance matching, and impedance matching.
XtremeESD® Protection Family: Superior Protection AND Outstanding Signal Integrity
California Micro Devices (CMD) Corporation is introducing the PicoGuard XP® and PicoGuard XS® ESD protection architectures. These new architectures are a game-changing solution for designers seeking to solve critical ESD protection and signal integrity concerns for advanced high speed data interfaces.
PicoGuard XP provides extreme protection for sensitive high speed ICs, such as USB where traditional single clamp architectures are not effective. The new PicoGuard XP architecture significantly reduces the clamping voltage and the amount of residual current that passes through to the protected system ICs and as result performs significantly better than the best ESD diode arrays on the market when protecting today's most sensitive system ICs. Picoguard XP devices are ideal for protecting ESD sensitive high speed data ports.
PicoGuard XS provides ESD protection for extreme high speed data interfaces where designers require robust ESD protection and no-compromise signal integrity performance. By integrating diodes with inductors to enable high frequency ESD protection and providing matching impedance without requiring external compensation, PicoGuard XS eliminates design and layout concerns, enables optimal signal integrity, improves ESD performance, and is an ideal solution for ports such as HDMI™ 1.3 and DisplayPort™.
The CMD ESD Design Resource Center
This site contains downloadable technical white papers, product specifications, articles and presentations on a variety of ESD protection topics (please use the navigation bars on the left side of the page). Your feedback on ESD protection and the usefulness of this site are important to us. If you'd like to comment, please visit the Feedback/Questions page. Additionally, please bookmark the site and check back as we'll be adding new ESD protection materials on a regular basis.
