Analog Devices’ family of multicell, high voltage battery stack monitors are complete battery monitoring ICs that include 16-bit ADCs, precision voltage references, a high voltage input multiplexer, and a serial interface. Parts can be connected in series, without optocouplers or isolators, to allow the monitoring of every cell in a long string of series-connected batteries. Applications include electric and hybrid electric vehicles, high power portable equipment, backup battery systems, and high voltage data acquisition systems.

The LTC®6811 is a multicell battery stack monitor that measures up to 12 series connected battery cells with a total measurement error of less than 1.2mV. The cell measurement range of 0V to 5V makes the LTC6811 suitable for most battery chemistries. All 12 cells can be measured in 290µs, and lower data acquisition rates can be selected for high noise reduction. 

Multiple LTC6811 devices can be connected in series, permitting simultaneous cell monitoring of long, high voltage battery strings. Each LTC6811 has an isoSPI interface for high speed, RF-immune, long distance communications. Using the LTC6811-1, multiple devices are connected in a daisy chain with one host processor connection for all devices. Using the LTC6811-2, multiple devices are connected in parallel to the host processor, with each device individually addressed. 

The LTC6811 can be powered directly from the battery stack or from an isolated supply. The LTC6811 includes passive balancing for each cell, with individual PWM duty cycle control for each cell. Other features include an onboard 5V regulator, five general purpose I/O lines and a sleep mode, where current consumption is reduced to 4µA. 

The LTC6813-1 is a multicell battery stack monitor that measures up to 18 series connected battery cells with a total measurement error of less than 2.2mV. The cell measurement range of 0V to 5V makes the LTC6813-1 suitable for most battery chemistries. All 18 cells can be measured in 290µs, and lower data acquisition rates can be selected for high noise reduction. 

Multiple LTC6813-1 devices can be connected in series, permitting simultaneous cell monitoring of long, high voltage battery strings. Each LTC6813-1 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 LTC6813-1 can be powered directly from the battery stack or from an isolated supply. The LTC6813-1 includes passive balancing for each cell, with individual PWM duty cycle control for each cell. Other features include an onboard 5V regulator, nine general purpose I/O lines and a sleep mode, where current consumption is reduced to 6µA. 

LTC6811-1 

LTC6813-1

Industrial, Electric and Hybrid Electric Vehicles, Backup Battery Systems, Grid Energy Storage, High Power Portable Equipment