FM LTH7R..

LTH7R.. is a constant-current/constant-voltage cradle charger management IC designed primarily for single-cell lithium battery charging. Its application circuit requires no external sense resistor, and the internal MOSFET structure eliminates the need for an external reverse-blocking diode. Under high power dissipation or elevated ambient temperature conditions, the IC automatically reduces charging current to limit junction temperature. The charge voltage is fixed, while the charge current is programmable via an external resistor. When the battery voltage reaches the float voltage and the charge current drops to 1/10 of the programmed value, the IC automatically terminates the charging process. Upon removal of the input voltage, the IC enters a low-current mode, drawing less than 5uA from the battery. In standby mode, the supply current is only 70uA. Additionally, the IC features charge current monitoring, voltage detection, automatic recharge, and provides a status pin for indicating charging state and battery full condition.

• Programmable charge current up to 500 mA
• No external MOSFET, sense resistor, or blocking diode required
• Constant-current/constant-voltage operation
• Thermal protection
• Li-ion battery charging via USB port
• 1% preset charge voltage accuracy
• Low supply current in standby mode
• Trickle charge threshold voltage: 2.9V
• Soft-start to limit inrush current
• SOT23-5 package

• Mobile phones
• PDAs
• MP3 players
• Bluetooth headsets