70V-tolerant, 12-cell battery sensor extends battery life, supports highest automotive safety rating

September 21, 2012 // By Paul Buckley
Maxim Integrated Products, Inc. has unveiled a fourth-generation high-voltage battery sensor for mission-critical automotive and industrial lithium-ion battery and fuel cell applications.

The MAX17823 offers a full suite of proprietary integrated ISO-26262 diagnostic features to help maximize the driving range of electric and hybrid electric vehicle while ensuring battery and fuel cell safety and reliability.

A proprietary, differential UART communications link is automotive EMC-hardened, enabling uninterrupted cell monitoring during battery pack service disconnect and eliminating costly digital isolators. An innovative shutdown feature safely enters all daisy-chain devices into submicro-ampere sleep mode when a host microcontroller loses 12 V power. ASIL-D (Automotive Safety Integrity Level ‘D’, per ISO-26262) compliance is achieved and maintained with unmatched, accurate 96-cell, 100 measurements-per-second performance. The 96-cell hot-plug immunity ensures highest reliability during battery management system (BMS) manufacturing.

The MAX17823’s accuracy is better than 2 mV cell voltage measurement and the device features comprehensive smart diagnostics to eliminate premature system shutdown.

Robust daisy-chain UART interface supports cable lengths of up to 3m and passes rigorous industry EMC-compliance testing while 96-cell hot-plug and cell-reversal immunity allows for safe pack assembly.

Maxim Integrated claims the device has the industry’s fastest cell measurement and diagnostic speed of 100 times per second.

Available in a 64-pin LQFP package (10mm × 10mm) the MAX17823 is specified across the -40 °C to +105 °C temperature range.

Maxim Integrated will be demonstrating the MAX17823 in an Automotive Battery Management System demo live at electronica 2012 (Munich, Germany, November 13 to 16 in Hall A6, Booth 163).

The demo will see a battery car running in a plexiglass oval track and the vehicle's lithium battery pack’s state of charge and health will be continuously monitored on a GUI dashboard via wireless communication. Live faults will be wirelessly activated during the demo to illustrate fault isolation and reporting capabilities. Maxim Integrated will be inviting participants to experiment with different driving styles to show how fuel economy can be maximized.

More information about the MAX17823 high-voltage battery sensor at
http://www.maximintegrated.com/datasheet/index.mvp/id/7816