Orders were up for Emerson Process Management’s largest-selling product when a supplier of a critical ASIC component unexpectedly issued an end-of-life notice for its part.
A major supplier of automation systems and instrumentation, Emerson had to come up with a new mixed-signal ASIC for its Rosemount 3051CDæan industrial differential pressure transmitteræand they needed to do it fast. The ASIC, known as the Marble sensor interface chip, accepts input from a capacitive pressure sensor and converts it to digital data for further processing.
With AMI Semiconductor (AMIS) as its development partner, Emerson finished the development project in less than 50 weeks, or about half the time generally required to execute such a project. But Terry Krouth, Emerson’s VP of technology, said it was no easy task.
"There was really no good alternative (to the Marble sensor chip)," said Krouth. "It offered low power, small size, reliability, and a good cost position. We couldn’t design it out."
Krouth said a second spin of silicon is needed for roughly half of Emerson’s IC projects. But with supplies of the marble chip dwindling, there wasn’t enough time. "Getting it right the first time was imperative."
Emerson selected AMIS as its ASIC development partner because it had worked successfully with AMIS on other ASICs, and because AMIS was willing to adapt its design flow to fit Emerson’s tight timeframe.
AMIS’ design flow begins with a detailed planning stage during which design and test specifications, statements of work and other technical definitions and resource plans are developed. AMIS spends more time in pre-study than is typical with most design flows, according to Krouth.
"Experience has shown that if more time is spent up-front, asking critical questions, there is a much higher probability of first time silicon success," he said. "Designers can focus on implementation of a detailed plan.