Linear Technology introduced the LTC4071, an easy-to-use, tiny shunt battery system for Li-Ion/Polymer batteries that integrates a charger and battery pack protection in one IC. The LTC4071, with its 550nA operating current, charges and protects batteries from previously unusable very low current, intermittent or continuous charging sources.
The LTC4071 can charge at currents up to 50mA. A near zero current (<0.1nA) low battery latching disconnect function protects even low capacity batteries from deep discharge and potentially irreparable damage. Housed in a low profile (0.75mm) 8-lead 2mm x 3mm DFN package, the LTC4071 provides the only complete and ultra-compact battery charger and protection solution operating with low level power sources. The device's feature set is well suited for high impedance, lower power charging source applications, such as energy scavenging/harvesting, resistive isolation or solar-powered systems.
With pin-selectable settings of 4.0V, 4.1V, or 4.2V, the LTC4071's 1% accurate battery float voltage allows the user to optimize the balance between battery capacity and lifetime. An independent high battery supervisory status output indicates a near-fully charged battery. The internal thermal battery conditioner reduces the float voltage to protect Li-Ion/Polymer cells at elevated battery temperatures. Multiple-cell battery stacks can be charged and balanced by configuring several LTC4071 ICs in series.