Multi-cell battery monitor measures up to 15 series-connected battery cells

Analog Devices LTC6812 15-Channel Multi-Cell Battery Monitor provides measurement for up to 15 series-connected battery cells with a complete measurement error of less than 2.2mV. The measurement range of 0V to 5V makes the device ideal for most battery chemistries. All 15 cells can be measured in 245μs, and lower data acquisition rates can be chosen for high noise reduction. Multiple devices can be combined in series, allowing simultaneous cell monitoring of long, high-voltage battery strings. Each monitor has an isoSPI interface for RF-immune, high-speed, long-distance communications. Multiple devices are joined in a daisy chain with one host processor connection for all of the monitors. This daisy chain can be run bi-directionally, securing communication integrity, even if there is a fault along the communication path.

The device can be powered straight from the battery stack or an isolated supply. The monitor comprises passive balancing for each cell, with individual PWM duty cycle control for each cell. Other highlights comprise an onboard 5V regulator, nine general-purpose I/O lines, and a sleep mode, where current consumption is decreased to 6µA.

Typical applications areas include electric and hybrid electric vehicles, backup battery systems, grid energy storage, and high power portable equipment.