Imagine if your smartphone or computer could repair on its own!
It
might sound like the stuff of science fiction as engineers at the
California Institute of Technology, for the first time ever, have
developed self-healing integrated chips.
It means your smartphones
or computers can repair and defend themselves on the fly, recovering in
microseconds from problems ranging from less-than-ideal battery power
to total transistor failure.
The team demonstrated this
self-healing capability in tiny power amplifiers, which are so small, in
fact, that 76 of the chips-including everything they need to
self-heal-could fit on a single penny.
They destroyed various
parts of their chips by zapping them multiple times with a high-power
laser, and then observed as the chips automatically developed a
work-around in less than a second.
"It was incredible the first
time the system kicked in and healed itself. It felt like we were
witnessing the next step in the evolution of integrated circuits," said
Ali Hajimiri, the Thomas G Myers Professor of Electrical Engineering at
Caltech.
"We had literally just blasted half the amplifier and
vaporised many of its components, such as transistors, and it was able
to recover to nearly its ideal performance," said Hajimiri in a
statement.
Until now, even a single fault has often rendered an
integrated-circuit chip completely useless. Engineers wanted to give
integrated-circuit chips a healing ability akin to that of our own
immune system-something capable of detecting and quickly responding to
any number of possible assaults in order to keep the larger system
working optimally.
The power amplifier they devised employs a
multitude of robust, on-chip sensors that monitor temperature, current,
voltage, and power.
The information from those sensors feeds into a
custom-made application-specific integrated-circuit (ASIC) unit on the
same chip, a central processor that acts as the "brain" of the system.
The
brain analyses the amplifier's overall performance and determines if it
needs to adjust any of the system's actuators-the changeable parts of
the chip.
Interestingly, the chip's brain does not operate based
on algorithms that know how to respond to every possible scenario.
Instead, it draws conclusions based on the aggregate response of the
sensors.
Looking at 20 different chips, the team found that the
amplifiers with the self-healing capability consumed about half as much
power as those without, and their overall performance was much more
predictable and reproducible.