The RT9501 is a single Lithium-Ion or Lithium-Polymer cell linear battery charger which is designed for compact and cost-sensitive handheld devices. It combines charge status indication, charge termination, battery temperature monitoring, and high accuracy current and voltage regulation in a MSOP-8 package. The RT9501 charges the battery in three modes, precharge, constant current, constant voltage. If the battery voltage is below the precharge threshold VO(MIN), the RT9501 precharges the battery with a lower conditioning current. After precharge, the RT9501 applies a constant current to the battery. An external senseresister sets the charge current. The constant voltage mode continues until the battery reaches the regulation voltage.