A new safety monitoring chip from ADI enables tier-one
automotive suppliers to design monitoring and protection systems for the
massive lithium-ion battery packs used in electric cars and plug-in hybrid
chip can monitor six cells at a time, and can be daisy-chained with other chips
to look for over-voltage, over-temperature or under-voltage conditions in
battery packs composed of hundreds or even thousands of cells.
the car manufacturers peace of mind," says Steve Boyle, product marketing
manager for Analog Devices Inc.
provides assurance that they can design a system that's safe." Boyle says the
technology could also be used for high-voltage industrial, automotive and
energy applications, such as wind turbines and photovoltaic cells.
the new safety monitoring chip is particularly significant for safety-related
applications, where high temperatures or voltages can damage batteries, or
worse, cause unsafe conditions. It's made up of a series of high-voltage
comparators that "look" for undesirable voltage or temperature conditions and
then work with an alarm to let the system know if any values have gone outside
a prescribed window of acceptability.
Devices engineers say that one of the big advantages of the device is that it
can be easily daisy-chained to work with large battery stacks. Because it's an
integrated package and not a conglomeration of discrete electronic components,
daisy-chaining of the AD8280 can also take place without a need for isolators
at each stage.
monitoring chip is incorporated in a 48-lead, low-profile quad flat package
(LQFP) that measures just 7 x 7 mm square.
build this up discretely, but the discrete systems take up more space and cost
a lot," says Sam Weinstein, a product manager for the AD8280. "We've been able
to integrate all these functions into one chip."