A major conundrum for the embedded industry is that while the cost of computer chips has fallen over the years, the design costs are growing. And increasingly, custom chips are required to drive up efficiency and drive down the size of connected devices, like smart thermometers that automatically adjust the temperature in a room and wristbands that track your health.
But in recent years, several companies have been trying to reduce the costs and amount of time involved in traditional chip development. Mountain View, California-based zGlue has developed a programmable silicon interposer technology that allows multiple die to be combined inside a single package, lowering the bar for what could be prohibitively costly custom chip design.
The 2.5D integration technology stretches the definition of custom silicon, enables system-on-chips to be assembled from preexisting parts the same way as one would put together a circuit board. The company recently introduced a new product with its own custom chip at Maker Faire in San Francisco. The product, zOrigin, is designed for wearable devices but it can be adapted to other devices, such as smart jewelry and fitness bands.
zOrigin is the first product based on an SoC developed with zGlue's chip stacking technology, which allows designers to assemble chips from chiplets or tiny bits of circuitry that range from memory to microcontrollers to sensors. The product can be preordered for $149, and the SoC inside is smaller than a dime, measuring only 11 millimeters by 27 millimeters.
The company – whose business model could be called semiconductors-as-a-service – has raised $9.1 million in funding since it was founded by former chip architects from Samsung Electronics and Advanced Micro Devices in 2014. zGlue has developed software tools that make it easier for embedded engineers to drop die into its silicon interposer.
The interposer approach differs from system-in-package technology – more commonly known as SiP – in which chips are stacked vertically and stitched together by wires bonded to the packaging. That technique saves space but costs more. zGlue’s ZiP technology is designed to speed up development, allowing chips to be manufactured at volume in as little as two months, while slashing size by an order of magnitude.
The plan is to have a storefront where designers can select chiplets from companies like NXP Semiconductors, Maxim Integrated and the company’s other partners. As long as the appropriate chiplets are available, zGlue’s integration platform could help significantly cut the costs of creating custom chips for compact embedded devices – and make them more accessible to developers.
San Mateo, California-based startup SiFive has a similar strategy. The company provides support around the RISC-V architecture, making it easy to commission custom chips for Internet of Things devices, data centers and other applications. The company, which recently raised $50.6 million in venture capital, is expanding its DesignShare program to provide intellectual property that can be puzzled together in custom chips.