Features: `Complete Linear Charger in 2mm * 2mm DFN Package
` C/10 Charge Current Detection Output
` Timer Termination
` Charge Current Programmable up to 750mA with 5% Accuracy
` No External MOSFET, Sense Resistor or Blocking Diode Required
` Preset 4.2V Float Voltage with 0.6% Accuracy
` Constant-Current/Constant-Voltage Operation with Thermal Feedback to Maximize Charging Rate Without Risk of Overheating
` ACPR Pin Indicates Presence of Input Supply (LTC4065A Only)
` Charge Current Monitor Output for Gas Gauging
` Automatic Recharge
` Charges Single Cell Li-Ion Batteries Directly from USB Port
` 20A Supply Current in Shutdown Mode
` Soft-Start Limits Inrush Current
` Tiny 6-Lead (2mm * 2mm) DFN PackageApplication·Wireless PDAs
·Cellular Phones
·Portable ElectronicsPinout
SpecificationsVCCt < 1ms and Duty Cycle < 1% .................. 0.3V to 7V
Steady State .................................................. 0.3V to 6V
BAT, CHRG ....................................................... 0.3V to 6V
EN (LTC4065), ACPR (LTC4065A)........ 0.3V to VCC + 0.3V
PROG.................................................. 0.3V to VCC + 0.3V
BAT Short-Circuit Duration ................................Continuous
BAT Pin Current ....................................................... 800mA
PROG Pin Current ..................................................... 800A
Junction Temperature (Note 6) ............................... 125°C
Operating Temperature Range (Note 2) .. 40°C to 85°C
Storage Temperature Range .................. 65°C to 125°CDescriptionThe LTC®4065 is a complete constant-current/constantvoltage linear charger for single-cell lithium-ion batteries. Its 2mm * 2mm DFN package and low external component count make the LTC4065 especially well-suited for portable applications. Furthermore, LTC4065 is specifically designed to work within USB power specifications.
The CHRG pin of LTC4065A 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.
No external sense resistor or blocking diode is required due to the internal MOSFET architecture. Thermal feedback regulates charge current to limit the die temperature during high power operation or high ambient temperature conditions.
When the input supply (wall adapter or USB supply) is removed, the LTC4065 automatically enters a low current state, dropping battery drain current to less than 1A. With power applied, LTC4065 can be put into shutdown mode, reducing the supply current to less than 20A.
The full-featured LTC4065 also includes automatic recharge, low-battery charge conditioning (trickle charging), soft-start (to limit inrush current) and an open-drain status pin to indicate the presence of an adequate input voltage (LTC4065A only).
The LTC4065 is available in a tiny 6-lead, low profile (0.75mm) 2mm * 2mm DFN package.
LTC4065A Data Sheet
