The ISL9214A is a fully integrated low-cost single-cell Li-ion

or Li-polymer battery charger. The charger accepts two

power inputs, normally one from a USB (Universal Serial

Bus) port and the other from a desktop cradle. The

ISL9214A is an ideal charger for smart handheld devices

that need to communicate with a personal computer via

USB.

The ISL9214A features 28V maximum voltages for both the

cradle and the USB inputs. Due to the 28V rated inputs,

low-cost, large output tolerance adapters can be used safely.

When both inputs are powered, the cradle input is used to

charge the battery. The charge current is programmable for

the cradle input with a small resistor. The end-of-charge

current is also programmable by another external resistor.

The charger incorporates Thermaguard™ which protects the

IC against over-temperature. If the die temperature rises

above a typical value of +125°C, a thermal foldback function

reduces the charge current automatically to prevent further

temperature rise. The charger has two indication pins. The

PPR (power present) pin outputs an open-drain logic LOW

when either the cradle or the USB input power is attached.

The CHG (charge) pin is also an open-drain output that

indicates a logic LOW when the charge current is above a

minimum current level. When the charge current is below the

preset minimum current, the CHG pin will indicate a logic

HIGH signal. This status is latched and will be reset under

one of the following events:

Features

• Complete Charger for Single-Cell Li-ion/Polymer Batteries

• Dual Input Power Sources for Cradle and USB

• Low Component Count

• Integrated Pass Elements

• Fixed 380mA USB Charge Current

• Programmable Cradle Charge Current

• Charge Current Thermaguard™ for Thermal

Protection

• 28V Maximum Voltages for Cradle and USB Inputs

• Adapter Presence and Charge Indications

• Less than 0.5µA Leakage Current Off the Battery When

No Input Power Attached

• Programmable End-of-Charge Current

• Ambient Temperature Range: -40°C to +85°C

• No External Blocking Diode Required

Applications

• Smart Handheld Devices

• Cell Phones, PDAs, MP3 Players

• Digital Still Cameras

• Handheld Test Equipment