Battery charger detects external power connections in mobile apps

Intersil Corp. has released the ISL9222A, a battery charger designed to detect auxiliary and external power connections in mobile devices.

The ISL9222A is a high input, single cell, Li-Ion battery charger IC that incorporates a charger and digital logic (OR gate) into a single chip. This compact package enables customers to create small footprint solutions. The ISL9222A's high level of integration and small size make it suitable for applications that require overvoltage protection, test fixture power detection or reverse blocking.

The ISL9222A accepts an input voltage up to 28V, but is disabled when the input voltage exceeds the overvoltage protection threshold (typically 7.2V) in order to prevent excessive power dissipation. The 28V rating eliminates the overvoltage protection circuit required with a low input voltage charger.

In addition, the charge current is user-programmable with an external resistor. When the battery voltage is lower than 2.55V, the charger preconditions the battery with 20 percent of the programmed charge current. The ISL9222A also features a thermal foldback function that protects the charger from over-temperature conditions.

The device also features 1 percent voltage accuracy. An indication pin (PPR) allows simple interface to a microprocessor or LED. When there is no adapter attached to the charger or when the charger is disabled, the ISL9222A draws less than 1?A leakage current from the battery.

The ISL9222A is available now in 8-lead TDFN packages, priced at $1.40 each in 1,000-unit quantities.