The LTC4069 is a complete constant-current/constantvoltage linear charger for single-cell lithium-ion batteries. The 2mm x 2mm DFN package and low external component count make the LTC4069 especially well-suited for portable applications. Furthermore, LTC4069 is specifically designed to work within USB power specifications. The CHRG pin indicates when charge current has dropped to ten percent of its programmed value (C/10). An internal timer terminates charging according to battery manufacturer specifications.