LTC4058X-4.2

Features:

Programmable Charge Current Up to 950mA
Complete Linear Charger in DFN Package
No MOSFET, Sense Resistor or Blocking DiodeRequired
Thermal Regulation Maximizes Charge RateWithout Risk of Overheating*
Battery Kelvin Sensing Improves Charging Accuracy
Charges Directly from a USB Port
C/10 Charge Termination
 Preset 4.2V Charge Voltage with ±1% Accuracy
Charge Current Monitor Output for Gas Gauging*
Automatic Recharge
Charge Status Output
"AC Present" Output
2.9V Trickle Charge Threshold (LTC4058)
Available Without Trickle Charge (LTC4058X)
Soft-Start Limits Inrush Current
Low Profile (3mm * 3mm * 0.75mm) DFN Package


Pinout




Specifications

(Note 1)
Input Supply Voltage (V_CC) ......................0.3V to 10V
PROG............................................. 0.3V to V_CC + 0.3V
BAT, BSENSE.............................................. 0.3V to 7V
CHRG, ACPR, EN  ......................................0.3V to 10V
BAT Short-Circuit Duration .......................... Continuous
BAT Pin Current ........................................................ 1A
PROG Pin Current ................................................... 1mA
Maximum Junction Temperature ......................... 125°C
Operating Temperature Range (Note 2) .. 40°C to 85°C
Storage Temperature Range ................. 65°C to 125°C


Description

The LTC®4058 is a complete constant-current/constant-voltage linear charger for single cell lithium-ion batteries.Its DFN package and low external component count makethe LTC4058 ideally suited for portable
applications.Furthermore, the LTC4058 is designed to work within USBpower specifications.

The LTC4058 can Kelvin sense the battery terminal formore accurate float voltage charging. No external senseresistor or external blocking diode are required due to theinternal MOSFET architecture. Thermal feedback regulatesthecharge current to limit the die temperature duringhigh power operation or high ambient temperature condi-tions. The charge voltage is fixed at 4.2V and the chargecurrent is programmed with a resistor. TheLTC4058terminates the charge cycle when the charge currentdrops to 10% of the programmed value after the final floatvoltage is reached.

When the input supply (wall adapter or USB supply) isremoved, the LTC4058 enters a low current state droppingthe battery drain current to less than 2µA. Other featuresinclude charge current monitor, undervoltage lockout,automatic recharge and status pins to indicate chargetermination and the presence of an input voltage.