Will Apple drive analog ICs?

January 11, 2016 //By Stephan Ohr
Analog expert Stephan Ohr turns his oscilloscope on the possible impact Apple could have with its new fab in San Jose. No one outside Apple knows what the iPhone giant will do with the 70,000-square foot analog production line it recently purchased from Maxim.

But Apple's extraordinary ability to get semiconductor suppliers to develop new devices for them — in fact, its ability to swallow entire companies without even belching — suggests Apple could influence the analog market for years to come. So it’s worth asking what Apple is currently doing in analog, what improvements would help them and how many of those improvements are manufacturing related.

We know the North First Street facility includes chip manufacturing equipment from Applied Materials, Hitachi, Novellus, and ASML. The fab will produce roughly 7,000 eight-inch wafers a month at geometries from 0.6-micron down to 90nm. Note: The sweet spot for analog manufacturing is still in the 0.35- to 0.18-micron range.

We also know that Apple has been buying an estimated $2-$2.5 billion a year in analog parts for its phones and tablets. The bulk of these parts include custom-made power management ICs (PMICs), less-custom audio codecs and a variety of sensors including motion sensors and touch-sensitive screens. If we were placing bets on which of the three part types Apple will tweak in the new facility, power management looks like the low-hanging fruit. No matter how cleverly crafted, the analog parts can turn into multi-sourced commodities. But shrinking power management functions remains a challenge.

With its Haswell-generation processors, for instance, Intel attempted to integrate power management functions onto the CPU. Its goal was to shrink the amount of space the PC motherboard devotes to power and cooling, and thus enable new miniaturized PC form factors. But machines that move dozens of amperes around are not easily shrunk, and Intel reverted back to more traditional Vcore regulator architectures.

In the case of mobile devices, the PMICs are custom-configured for each phone or tablet, and — depending on the feature set of the phone, can be quite complicated. There are as many 26 or 28 separate devices on one chip, including two or three 300 mA switch-mode regulators, 22 or 24 low-drop out regulators (LDOs), a lithium-Ion battery charge monitor controller, and several LED backlight drivers. Apple uses Dialog Semiconductor as the supplier for these parts.

It takes a lot of hard work, rather than any special tricks, to do this integration: You want the LDOs and other voltage controllers to sequence devices on-and-off (or to clock them down) in response to commands from the cell phone applications and baseband processors.

The BiCMOS or BCD processes used to implant power transistors on a CMOS substrates are now well-known — even among the Asia-based foundries that needed to unlearn memory manufacturing to serve analog clients. The power transistor implants buffer the power sources (batteries or AC adapters) from the CMOS control logic fabricated in 0.18- or 0.13-micron CMOS. We bet money that the fabrication facility Apple acquires from Maxim includes a transistor implant mechanism.

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