8 Channel Multicell Battery Monitor

The ADBMS6817 is a multicell battery stack monitor that measures up to 8 series connected battery cells with a lifetime total measurement error (TME) of less than 1.5 mV. The cell measurement range of 0 V to 5 V makes the ADBMS6817 suitable for most battery chemistries. All 8 cells can be measured in 304 μs, and lower data acquisition rates can be selected for high noise reduction.

Multiple ADBMS6817 devices can be connected in series, permitting simultaneous cell monitoring of long, high voltage battery strings. Each ADBMS6817 has an isoSPI™ interface for high speed, RF immune, long distance communications. Multiple devices are connected in a daisy chain with one host processor connection for all devices. This daisy chain can be operated bidirectionally, ensuring communication integrity even in the event of a fault along the communication path.

The ADBMS6817 can be powered directly from the battery stack or from an isolated supply. The ADBMS6817 includes passive balancing for each cell, with individual pulse-width modulation (PWM) duty cycle control for each cell. Other features include an on-board 5 V regulator, seven general-purpose input/output (GPIO) lines, and a sleep state, where current consumption is reduced to 5.5 μA.

The ADBMS6817WFS models are developed for use in ISO 26262 applications for Automotive Safety Integrity Level Capability D (ASIL D).

APPLICATIONS

* Electric and hybrid electric vehicles

* Backup battery systems

* Grid energy storage

* Large portable power banks

* Measures up to 8 battery cells in series

* Maximum lifetime total measurement error: 1.5 mV

* Stackable architecture for high voltage battery packs

* Built-in isoSPI interface

* 2 Mb isolated serial communications

* Uses a single twisted pair, up to 20 meters

* Low EMI susceptibility and emissions

* Bidirectional for broken wire protection

* Capacitor or transformer coupled

* Hot plug tolerant without external protection

* ADBMS6817WFS models are developed for use in ISO 26262 applications for Automotive Safety Integrity Level Capability (ASIL D)