The AD8280 is a hardware-only safety monitor for lithium ionbattery stacks. The device has inputs to monitor six battery cellsand two temperature sensors (either NTC or PTC thermistors).The device is designed to be daisy-chained with additional AD8280devices to monitor a stack of significantly more than six cellswithout the need for numerous isolators. The output can beconfigured for an independent or shared alarm state.

The AD8280 functions independently from a primarymonitor and contains a reference and LDO, both of which arepowered completely from the battery cell stack. The reference, inconjunction with external resistor dividers, establishes trip pointsfor the overvoltages and undervoltages. Each cell channel containsprogrammable deglitching circuitry to prevent alarms fromtransient input levels.

The AD8280 also has two digital pins that can select variouscombinations of inputs in the case where fewer than six cells areto be monitored. Most important, it has a self-test feature, makingit suitable for high reliability applications, such as automotivehybrid electric vehicles or higher voltage industrial usage, such asuninterruptible power supplies. The AD8280 can function over atemperature range of −40°C to +105°C.

Applications

• Lithium ion battery backup monitor and threshold detection
• Electric and hybrid electric vehicle
• Industrial vehicle
• Uninterruptible power supply
• Wind and solar

This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.