Analog Devices Inc./Maxim Integrated

The LTC4069-4.4 is a complete constant-current/constant-voltage linear charger for high capacity single-cell lithium-ion batteries with a 4.4V float voltage. The 2mm × 2mm DFN package and low external component count make the LTC4069-4.4 especially well-suited for portable applications. Furthermore, LTC4069-4.4 is specifically designed to work within USB power specifications.TheCHRGpin 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 LTC4069-4.4 automatically enters a low current state, dropping battery drain current to less than 1µA. With power applied, LTC4069-4.4 can be put into shutdown mode, reducing the supply current to less than 20µA.The LTC4069-4.4 also includes automatic recharge, lowbattery charge conditioning (trickle charging), soft-start (to limit inrush current) and an NTC thermistor input used to monitor battery temperature.The LTC4069-4.4 is available in a tiny 6-lead, low profile (0.75mm) 2mm × 2mm DFN package.Float VoltageLTC40694.2VLTC4069-4.44.4VApplicationsWireless PDAsCellular PhonesPortable Electronics

The LTC4075HVX is a standalone linear charger that is capable of charging a single-cell Li-Ion/Polymer battery from both wall adapter and USB inputs. The charger can detect power at the inputs and automatically select the appropriate power source for charging.No external sense resistor or blocking diode is required for charging due to the internal MOSFET architecture. The LTC4075HVX features a maximum 22V rating for both wall adapter and USB inputs although charging stops if the selected power source exceeds the overvoltage limit. Internal thermal feedback regulates the battery charge current to maintain a constant die temperature during high power operation or high ambient temperature conditions. The float voltage is fixed at 4.2V and the charge current is programmed with an external resistor. The LTC4075HVX terminates the charge cycle when the charge current drops below the programmed termination threshold after the final float voltage is reached.Other features include automatic recharge, undervoltage lockout, charge status outputs, and "power present" status outputs to indicate the presence of wall adapter or USB power. No trickle charge allows full current from the charger when a load is connected directly to the battery.Trickle ChargeVin Abs MaxLTC4075Yes10VLTC4075XNo10VLTC4075HVXNo22VApplicationsCellular TelephonesHandheld ComputersPortable MP3 PlayersDigital Cameras

The LTC4076 is a standalone linear charger that is capable of charging a single-cell Li-Ion battery from both wall adapter and USB inputs. The charger can detect power at the inputs and automatically select the appropriate power source for charging.No external sense resistor or blocking diode is required for charging due to the internal MOSFET architecture. Internal thermal feedback regulates the battery charge current to maintain a constant die temperature during high power operation or high ambient temperature conditions. The float voltage is fixed at 4.2V and the charge current is programmed with an external resistor. The LTC4076 terminates the charge cycle when the charge current drops below the user programmed termination threshold after the final float voltage is reached. The LTC4076 can be put into shutdown mode reducing the DCIN supply current to 20µA, the USBIN supply current to 10µA, and the battery drain current to less than 2µA even with power applied to both inputs.Other features include automatic recharge, undervoltage lockout, charge status output, power present status output to indicate the presence of wall adapter or USB power and high power/low power mode (C/5) for USB compatible applications.ApplicationsCellular TelephonesHandheld ComputersPortable MP3 PlayersDigital Cameras

The LTC4077 is a standalone linear charger that is capable of charging a single-cell Li-Ion battery from both wall adapter and USB inputs. The charger can detect power at the inputs and automatically select the appropriate power source for charging.No external sense resistor or blocking diode is required for charging due to the internal MOSFET architecture. Internal thermal feedback regulates the battery charge current to maintain a constant die temperature during high power operation or high ambient temperature conditions. The float voltage is fixed at 4.2V and the charge current is programmed with an external resistor. The LTC4077 terminates the charge cycle when the charge current drops below the termination threshold after the final float voltage is reached. The LTC4077 can be put into shutdown mode reducing the DCIN supply current to 20µA, the USBIN supply current to 10µA, and the battery drain current to less than 2µA even with power applied to both inputs.Other features include automatic recharge, undervoltage lockout, charge status output, power present status output to indicate the presence of wall adapter or USB power and high power/low power adjustable mode for USB compatible applications.ApplicationsCellular TelephonesHandheld ComputersPortable MP3 PlayersDigital Cameras

The LTC4078/LTC4078X are standalone linear chargers that are capable of charging a single-cell Li-Ion/Polymer battery from both wall adapter and USB inputs. The chargers can detect power at the inputs and automatically select the appropriate power source for charging.No external sense resistor or blocking diode is required for charging due to the internal MOSFET architecture. The LTC4078/LTC4078X feature a maximum 22V rating for both wall adapter and USB inputs, although charging stops if the selected power source exceeds the overvoltage limit. Internal thermal feedback regulates the battery charge current to maintain a constant die temperature during high power operation or high ambient temperature conditions. The float voltage is fixed at 4.2V and the charge current is programmed with an external resistor. The LTC4078/LTC4078X terminate the charge cycle when the charge current drops below the programmed termination threshold after the final float voltage is reached.Other features include battery present detection, automatic recharge, undervoltage lockout, charge status outputs, and "power present" status outputs to indicate the presence of wall adapter or USB power. The device is offered in a low profile (0.75mm) 3mm × 3mm 10-lead DFN package.ApplicationsCellular TelephonesHandheld ComputersPortable MP3 PlayersDigital Cameras

The LTC4079 is a low quiescent current, high voltage linear charger for most battery chemistry types including Li-Ion/Polymer, LiFePO4, Lead-Acid or NiMH battery stacks up to 60V. The maximum charge current is adjustable from 10mA to 250mA with an external resistor. The battery charge voltage is set using an external resistor divider.With an integrated power device, current sensing and reverse current protection, a complete charging solution using the LTC4079 requires very few external components. Thermal regulation ensures maximum charge current up to the specified limit without the risk of overheating. Charging can be terminated by either C/10 or adjustable timer.Input voltage regulation reduces charge current when the input voltage falls to an adjustable level or the battery voltage, making it well suited for energy harvesting applications. Other features include temperature qualified charging, bad battery detection, automatic recharge with sampled feedback in standby for negligible battery drain, and an open-drainCHRGstatus output. The device is offered in a compact, thermally enhanced 10-lead (3mm × 3mm) DFN package.APPLICATIONSEmbedded Automotive and IndustrialBackup Battery Charging from Another BatteryEnergy Harvesting ChargerThin Film Battery Products