The MAX11080/MAX11081 are a battery-pack fault-monitor ICs capable of monitoring up to 12 lithium-ion (Li+) battery cells. These devices are designed to provide an overvoltage or undervoltage fault indication when any of the cells cross the user-selectable threshold for longer than the set program-delay interval. The overvoltage levels are pin selectable from +3.3V to +4.8V in 100mV increments, and have a guaranteed accuracy of ±25mV over the entire temperature range. The undervoltage level is also user selectable from +1.6V to +2.8V in 200mV increments. These levels are guaranteed to ±100mV over the entire temperature range. Undervoltage detection can be disabled as one of the user-configuration options.

The MAX11080/MAX11081 have a built-in level-shifter that allows up to 31 MAX11080/MAX11081 devices to be connected in a daisy-chain fashion to reduce the number of interface signals needed for large stacks of series batteries. Each cell is monitored differentially and compared to the overvoltage and undervoltage thresholds. When any of the cells exceed this threshold for longer than the set program delay interval, the MAX11080/MAX11081 inhibit the heartbeat signal from being passed down the daisy-chain. Built-in comparator hysteresis prevents threshold chattering.

The MAX11080/MAX11081 are designed to be the perfect complement to the MAX11068 high-voltage measurement IC for redundant fault-monitoring applications. These devices are offered in a 9.7mm x 4.4mm, 38-pin TSSOP package with 0.5mm pin spacing. The package is lead-free and RoHS compliant with an extended operating temperature range of -40°C to +105°C.