By I-MicroNews
Sunday, November 22, 2009
Sand 9 caps its MEMS oscillator chips
with a CMOS ASIC to create an integrated two-chip stack
According to a press release from
EETimes. Micro-electro-mechanical systems (MEMS) have for the
first time matched the performance of their high-end rivals,
temperature compensated quartz crystals (TCXO), allowing them to
compete in mainstream markets for 3G/4G handsets, GPS navigators
and WiFi, according to startup Sand 9 Inc., which unveiled the new
company today at the Precise Time and Time Interval Systems and
Applications Meeting in Santa Ana Pueblo, N.M.
Sand 9 (Boston) revealed its high-precision MEMS technology
after spending the last two years secretly developing the
technology with $10.7 million in seed funding from Flybridge
Capital Partners, General Catalyst Partners and Khosla Ventures.
Sand 9 is lead by co-founder Matt Crowley, vice president of
corporate development, and founder Pritiraj Mohanty, chief
technology officer and inventor of its MEMS technology.
Mohanty is a physicist at Boston University where he has
demonstrated novel timing inventions in the past, such as a
nanoscale electro-mechanical system (NEMS) that exhibited
quantum-mechanical motion by jumping between two discrete positions
without passing through the physical space between them.
Two years ago, Mohanty and Crowley spun-off Sand 9 from Boston
University to develop Mohanty's novel MEMS oscillator structures
into what has become the worlds' most precise silicon oscillator,
which is capable of competing with the high-precision quartz
crystal oscillators used by mainstream original equipment
manufacturers in 3G/4G cell phones, global positioning systems
(GPS), WiFi and other high-precision applications.
"In a nutshell, we have a MEMS oscillator with performance
characteristics on par with the temperature compensated crystal
oscillators [TCXO] what we call temperature compensated MEMS
oscillator, or TCMO," said Crowley.
Other MEMS oscillator makers have been forced to relegate their
sales to markets where ultra-high precision is not required, even
though they are working today toward products aimed at the TCXO
market, which is becoming the high-volume sweet spot for
oscillators, as consumers move into 3G/4G handsets which require
higher precision clocks.
"This is the major breakthrough that will enable MEMS
oscillators to penetrate the core markets for crystal oscillators,"
said Crowley. "We have several orders of magnitude [over 100-times]
less phase noise than our competitor's MEMS oscillators."
Sand 9's chips, which are currently being sampled and will be
available for volume deliverly in 2010, cap the MEMS element with a
CMOS application specific integrated circuit to create an
integrated two-chip stack. Nevertheless, the chips are still
thinner and smaller than their competitors, measuring just
.5-by-.1.5-by-.8 millimeters. The ultra-small size combined with
high precision give Sand 9 a leg up on landing major design wins in
the high-volume market for 3G/4G mobile phones, although the
company has not yet secured any major contracts.
Sand 9 claims to have 24 patents protecting the various aspects
of the MEMS designs that make its devices superior to other MEMS
oscillators and rivals to the best crystal oscillators, but at a
lower cost and a smaller form factor. The most obvious difference
with Sand 9's design is its use of a higher base frequency for its
oscillator (124 MHz compared to 5 MHz) and its use of analog
temperature compensation techniques. These improvements, plus a
novel MEMS resonator structure, enable Sand 9 to achieve ultra-low
phase jitter (less than 90 femtoseconds) simultaneously with
ultra-high frequency stability over a wide temperature range (plus
or minus 2.5 parts per million, PPM, from -40 to +85 degrees
Celsius).
Sand 9's first priority is to deliver on its promise with
foundry-made parts in high volume next year, but the company
already has plans for the future. Next it plans to integrate
different frequencies of MEMS oscillators onto the same die,
beginning with adding a 32-kHz real-time clock alongside the main
system clock, which can be programmed at the factory to be anywhere
from 10-to-160 MHz. Eventually the company plans to migrate its
unique approach to the nanoscale fabrication to other types of MEMS
devices besides oscillators too.
http://www.eetimes.com/news/latest/showArticle.jhtml?articleID=221900341
SOURCE