Analog Evolves Into Mixed Signal

Predictions about the Internet of Things suggest this may be the new “Killer App,” something the semiconductor industry has long been looking for. Reinforcing the forecasts are television commercials from companies such as Cisco and GE touting the IoT’s impact on everything from jet engines to robots, capturing everyone’s imagination. New categories of products such as smartwatches will enable individuals to tap into the Internet of Things and analysts foresee anywhere from tens of billions to a trillion devices will connect to the Internet in the next few years. Everyone has a vision for the nascent market segment.

All of this is possible because of an evolution in semiconductor design and integration that well serve IoT applications, and bodes well for antifuse non-volatile memory (NVM) storage.

Take, for instance, the EM773, a low-cost 32-bit ARM Cortex-M0-based smart meter control chip from NXP Semiconductors that won the “EDN Analog Product of the Year” in 2012. It beat out product offerings from traditional analog vendors, including Linear Technology and the mighty Analog Devices, representing a transformation that signaled to the industry that analog semiconductor circuits were evolving into mixed-signal subsystems … finally.

In addition, the transition meant that analog semiconductor companies manufacturing on analog processes above 180nm now were beginning to design on digital logic processes at 180nm and below. That means if a design team is doing a full-spectrum analog to digital (A/D) converter, processes as advanced as 28nm deliver a much better solution and provide a competitive advantage for companies breaking into the IoT market.

These technological moves, however, are obsoleting flash. Once the main storage medium on microcontrollers, flash is not available at 40nm and smaller process nodes. Nor is it a particularly good fit for mixed-signal applications. As these mixed-signal designs migrate to smaller processes, memory becomes a consideration for code storage, security, calibration, code patching and customization, and a perfect opportunity for antifuse NVM. The additional mask layers and manufacturing steps to fabricate flash boosts cost on devices going into low-cost applications. In addition, the temperature extremes where devices such as a smart meter operate also makes flash less attractive.

Flash’s cost and inability to scale are creating demand for antifuse NVM. It’s a great fit for many IoT applications because it is frugal on cost, both in terms of R&D and minimizing the need for additional layers to the implementation. After all, adding cost is counterproductive to the value of the application.

The migration of mixed-signal designs to smaller process geometries also is having an effect on the multi-billion dollar foundry industry. Texas Instruments is the only analog company with a 300mm fab, giving TI a competitive advantage because devices fabricated on a 300mm wafer have a 30% lower cost than those on a 200mm wafer. The move to 300mm wafers and the economies of scale leverages the customization capabilities afforded by antifuse NVM. As IoT applications become more prominent, other analog and mixed-signal competitors that have done well with older fabrication equipment will find themselves at a significant disadvantage.

The market is going mixed signal. Cost advantages make it an easy choice for the Internet of Things developers. Customization requirements of IoT applications are demanding antifuse NVM storage and developers are taking a hard look at this versatile technology.