Lithium-ion batteries are difficult to handle; they need to be
constantly monitored. Chip maker Maxim Integrated Products has introduced
the fourth generation of its high-voltage sensor for drive train
batteries in e-cars. The MAX17823 features a full package of integrated
safety diagnosis functions according to the safety standard ISO26262.
The device contributes to extending the driving range of electric
vehicles while at the same time optimizing the safety and reliability of
batteries and fuel cells.
The device is also equipped with a proprietary UART
communication interface with differential PHY. With this interface, the
chip offers excellent EMI behaviour as required for automotive
environments. It does away with expensive digital isolators or
optocouplers and facilitates uninterrupted cell monitoring even when the
battery is disconnected for maintenance. An innovative switch-off
system puts all downstream devices into sleep mode with power
consumption of less than 1µA if the power supply to the host
microcontroller is disconnected. ASIL D safety requirements are met
through the precise measurements of up to 96 cells in an extremely fast
cycle of 100 measurements per second. The hot-plug capability at the
battery connections guarantees highest levels of reliability for design
and production of battery management systems (BMS).
The device measures the voltages at an accuracy of 2mV or better.
Comprehensive intelligent diagnosis functions prevent the system from
premature shutdown. The daisy-chain design of the UART supports cable
lengths of up to 3 meters and meets highest industrial and automotive
EMI requirements. The operating temperature range covers the span from
-40°C to +105°C. The device comes in an LQFP package.
For more information, visit http://www.maximintegrated.com/datasheet/index.mvp/id/7816
This story originally appeared in EE Times Europe.