Analog Devices

The LTC4091 is a 36V Li-Ion battery charger and power backup manager. The integrated step-down switching regulator charges a battery from a primary power source while providing power to the load. If primary power is lost, the load is seamlessly transitioned to the backup Li-ion/polymer battery. To protect sensitive downstream loads, the maximum output voltage is 4.45V.The LTC4091 provides an adaptive output that tracks the battery voltage for high efficiency charging. The charge current is programmable and an end-of-charge status output (CHRG) indicates full charge. Also featured is a termination timer and an NTC thermistor input used to monitor battery temperature while charging.During backup, an internal 75mΩ ideal diode connects the battery to the load. An optional external ideal diode FET driver is available to reduce the voltage drop even further. 4.1V or 4.2V battery charge voltages can be selected.ApplicationsFleet and Asset TrackingAutomotive GPS Data LoggersAutomotive Telematics SystemsBattery Backup Systems

The LTC4095 is a complete constant-current/constant-voltage linear charger for single-cell lithium-ion/polymer batteries. Its small 2mm × 2mm DFN package and low external component count make the LTC4095 especially well-suited for portable USB power applications.Up to 950mA of charge current may be programmed via a single resistor from the PROG pin to ground. The HPWR pin allows the charge current to be set at 20% or 100% of its full-scale programmed value. An internal safety timer terminates charge current. The final float voltage is preset to 4.2V and held to a tight 0.5% tolerance. Also featured is an NTC thermistor input to monitor battery temperature while charging, a C/10 current detection output, automatic recharge, bad-battery detection and low-battery trickle charge. A thermal feedback loop regulates the charge current to limit the die temperature during high power operation or high ambient thermal conditions.The LTC4095 is available in a tiny, low profile (0.75mm) 8-lead 2mm × 2mm DFN package.ApplicationsPDAsMedia PlayersCellular PhonesOther Portable Electronics

The LTC4097 is a standalone linear battery charger that is capable of charging a single-cell Li-Ion or Li-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. 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 LTC4097 terminates the charge cycle when the charge current drops below the user programmed termination threshold after the final float voltage is reached. The LTC4097 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 trickle charge, automatic recharge, undervoltage lockout, charge status output, an NTC thermistor input used to monitor battery temperature and VNTC power present output with 120mA drive capability.ApplicationsCellular TelephonesMP3 PlayersPortable Handheld Devices

The LTC4098-3.6 is a high efficiency USB PowerPath controller and full-featured LiFePO4battery charger. It seamlessly manages power distribution from multiple sources including USB, wall adapter, automotive, Firewire or other high voltage DC/DC converters, and a LiFePO4battery.The LTC4098-3.6 charge algorithm is optimized for LiFePO4by implementing a 1-hour float voltage termination timer and a 0°C to 60°C NTC-based charge qualification range. Furthermore, completely discharged batteries are charged at the full programmed charge current.The LTC4098-3.6’s switching regulator can automatically limit its input current for USB compatibility. For automotive and other high voltage applications, the LTC4098‑3.6 interfaces with an external switching regulator. Both the USB input and the auxiliary input controller feature Bat-Track optimized charging to provide maximum power to the application and reduced heat in high power density applications with input supplies from 5V to as high as 38V.An overvoltage protection circuit guards the LTC4098-3.6 from high voltage damage on the VBUS pin with just two external components.The LTC4098-3.6 is available in a 20-lead 3mm × 4mm × 0.75mm QFN surface mount package.Float VoltageLTC40984.2V (1-cell Li-Ion/Li-Polymer)LTC4098-14.1V (1-cell Li-Ion/Li-Polymer)LTC4098-3.63.6V (1-cell LiFePO4)ApplicationsHigh Peak Power Battery-Powered EquipmentBackup ApplicationsHigh Reliability Handhelds

The LTC4099 is an I2C controlled high efficiency USB PowerPath™controller and full-featured Li-Ion/Polymer battery charger. It seamlessly manages power distribution from multiple sources including USB, a wall adapter and a Li-Ion/Polymer battery.The LTC4099 automatically limits its input current for USB compatibility. For automotive and other high voltage applications, the LTC4099 interfaces with an external switching regulator. Both the USB input and the auxiliary input controller feature Bat-Track optimized charging to provide maximum power to the application and reduced heat in high power density applications.The I2C port allows digital control of important application parameters including input current limit, charge current and float voltage. Several status bits can also be read back via I2C.An overvoltage protection circuit guards the LTC4099from high voltage damage on the low voltage VBUSpin.TheLTC4099 is available in a 20-Lead 3mm × 4mm × 0.75mmQFN Package.ApplicationsMedia PlayersPortable Navigation DevicesSmart PhonesIndustrial HandheldsPortable Medical Instruments

The LTC4100 Smart Battery Charger is a single chip charging solution that dramatically simplifies construction of an SBS compliant system. The LTC4100 implements a Level 2 charger function whereby the charger can be programmed by the battery or by the host. A SafetySignal on the battery being charged is monitored for temperature, connectivity and battery type information. The SMBus interface remains alive when the AC power adapter is removed and responds to all SMBus activity directed to it, including SafetySignal status (via the ChargerStatus command). The charger also provides an interrupt to the host whenever a status change is detected (e.g., battery removal, AC adapter connection).Charging current and voltage are restricted to chemistry specific limits for improved system safety and reliability. Limits are programmable by two external resistors. Additionally, the maximum average current from the AC adapter is programmable to avoid overloading the adapter when simultaneously supplying load current and charging current. When supplying system load current, charging current is automatically reduced to prevent adapter overload.ApplicationsPortable Instruments and ComputersData Storage Systems and Battery Backup Servers

The LTC4110 is a complete single chip, high efficiency, flyback battery charge and discharge manager with automatic switchover between the input supply and the backup battery or super capacitor. The IC provides four modes of operation: battery backup, battery charge, battery calibration and shutdown. Battery backup and battery charge are automatic standalone modes, while the optional calibration mode requires a CPU host to communicate over an SMBus. During calibration the flyback charger is used in reverse to discharge the battery with a programmable constant current into the system load eliminating heat generation. Three status outputs can be individually reconfigured over the SMBus to become GPIOs. User programmable over-discharge protection is provided. The SHDN pin isolates the battery to support shipping the product with a charged battery installed.Multiple LTC4110s can be combined to form a redundant battery backup system or increase the number of battery packs to achieve longer backup run times.The LTC4110 is available in a low profile (0.75mm), 38-pin 5mm × 7mm QFN package. The QFN features an exposed metal die mount pad for optimum thermal performance.ApplicationsBackup Battery SystemsServer Memory BackupMedical EquipmentHigh Reliability Systems

The LTC4120 is a constant-current/constant-voltage wireless receiver and battery charger. An external programming resistor sets the charge current up to 400mA. The LTC4120-4.2 is suitable for charging Li-Ion/Polymer batteries, while the programmable float voltage of the LTC4120 accommodates several battery chemistries. The LTC4120 uses a Dynamic Harmonization Control (DHC) technique that allows high efficiency contactless charging across an air gap.The LTC4120 regulates its input voltage via the DHC pin. This technique modulates the resonant frequency of a receiver tank to automatically adjust the power received as well as the power transmitted to provide an efficient solution for wirelessly charging battery-powered devices.Wireless charging with the LTC4120 provides a method to power devices in harsh environments without requiring expensive failure-prone connectors. This allows products to be charged while locked within sealed enclosures, or in moving or rotating equipment, or where cleanliness or sanitation is critical.This full featured battery charger includes accurate RUN pin threshold, low voltage battery preconditioning and bad battery fault detection, timer termination, auto-recharge, and NTC temperature qualified charging. TheFAULTpin provides an indication of bad battery or temperature faults.Once charging is terminated, the LTC4120 signals end-of-charge via theCHRGpin, and enters a low current sleep mode. An auto-restart feature starts a new charging cycle if the battery voltage drops by 2.2%.ApplicationsHandheld InstrumentsIndustrial/Military Sensors and DevicesHarsh EnvironmentsPortable Medical DevicesPhysically Small DevicesElectrically Isolated Devices

The LTC4121 is a 400mA constant-current/constantvoltage (CC/CV) synchronous step-down battery charger. In addition to CC/CV operation, the LTC4121 regulates its input voltage to a programmable percentage of the input open-circuit voltage. This technique maintains maximum power transfer with high impedance input sources such as solar panels.An external resistor programs the charge current up to 400mA. The LTC4121-4.2 is suitable for charging Li-Ion/ Polymer batteries, while the programmable float voltage of the LTC4121 is suitable for several battery chemistries.The LTC4121 and LTC4121-4.2 include an accurate RUN pin threshold, low voltage battery preconditioning and bad battery fault detection, timer termination, auto-recharge, and NTC temperature qualified charging. TheFAULTpin provides an indication of bad battery or temperature faults.Once charging is terminated, the LTC4121 signals end-ofcharge via theCHRGpin, and enters a low current SLEEP mode. An auto-restart feature starts a new charging cycle if the battery voltage drops by 2.2%.ApplicationsHandheld InstrumentsSolar Powered DevicesIndustrial/Military Sensors and Devices