The MAX17435/MAX17535 integrated multichemistry battery chargers IC simplify construction of accurate and efficient chargers. The MAX17435/MAX17535 provide SMBus™-programmable charge current, charge voltage, input current limit, relearn voltage, and digital readback of the IINP voltage. The MAX17435/MAX17535 utilize a charge pump to control the adapter selection n-channel MOSFETs when the adapter is present. When the adapter is absent, the charge pump is shut down and a p-channel MOSFET selects the battery.The MAX17435/MAX17535 provide up to 7A of charge current to 2, 3, or 4 lithium-ion (Li+) cells in series. The charge current, and input current-limit sense amplifiers have low offset errors and can use 10mΩ sense resistors. The MAX17435/MAX17535 fixed-inductor ripple architecture significantly reduces component size and circuit cost.The MAX17435/MAX17535 provide a digital output that indicates the presence of the adapter, an analog output that indicates the adapter or battery current, depending upon the presence or absence of the adapter, and a digital output that indicates when the adapter current exceeds a user-defined threshold.The MAX17435 switches at 850kHz, and the MAX17535 switches at 500kHz.The MAX17435/MAX17535 are available in a small, 4mm x 4mm x 0.75mm 24-pin, lead-free QFN package. An evaluation kit is available.Applications2- to 4-Li+ Cell Battery-Powered DevicesNotebook ComputersPDAs and Mobile Communicators

The MAX8903A–MAX8903E/MAX8903G/MAX8903H/MAX8903J/MAX8903N/MAX8903Y are integrated 1-cell Li+ chargers and Smart Power Selectors™ with dual (AC adapter and USB) power inputs. The switch mode charger uses a high switching frequency to eliminate heat and allow tiny external components. It can operate with either separate inputs for USB and AC adapter power, or from a single input that accepts both. All power switches for charging and switching the load between battery and external power are included on-chip. No external MOSFETs, blocking diodes, or current-sense resistors are required.The MAX8903_ feature optimized smart power control to make the best use of limited USB or adapter power. Battery charge current and SYS output current limit are independently set. Power not used by the system charges the battery. Charge current and SYS output current limit can be set up to 2A while USB input current can be set to 100mA or 500mA. Automatic input selection switches the system from battery to external power. The DC input operates from 4.15V to 16V with up to 20V protection, while the USB input has a range of 4.1V to 6.3V with up to 8V protection.The MAX8903_ internally block current from the battery and system back to the DC and USB inputs when no input supply is present. Other features include prequal charging and timer, fast charge timer, overvoltage protection, charge status and fault outputs, power-OK monitors, and a battery thermistor monitor. In addition, on-chip thermal limiting reduces battery charge rate and AC adapter current to prevent charger overheating. The MAX8903_ is available in a 4mm x 4mm, 28-pin thin QFN package.The various versions of the MAX8903_ allow for design flexibility to choose key parameters such as system regulation voltage, battery prequalification threshold, and battery regulation voltage. The MAX8903B/MAX8903E/MAX8903G also includes power-enable on battery detection. See the Selector Guide section in the full data sheet for complete details.ApplicationsMobile Internet DevicesPDA, Palmtop, and Wireless HandheldsPersonal Navigation DevicesPortable Multimedia PlayersSmart Cell PhonesUltra Mobile PCs

The DS2746 remains in production, however, for new projects, we recommend ModelGauge m5 MAX17055 fuel gauge.The DS2746 provides system-side battery capacity monitoring in cost-sensitive applications. Voltage, bidirectional current, and accumulated current measurement data is provided to the host processor over a 2-wire interface. Offset bias and offset blanking features greatly enhance the accuracy of the coulomb counter. In addition, the DS2746 has two auxiliary A/D inputs to sample the pack identification resistor, thermistor, or other voltage source. The results are reported as a ratiometric fraction of the supply voltage eliminating error related to the supply. The DS2746 reduces the total power consumption of the measurement circuit by enabling the resistor dividers, through the VOUT pin, only while measurements are made. When the system is inactive, a low power sleep mode reduces current consumption while maintaining the coulomb count. The tiny 3mm × 3mm TDFN package consumes only 9mm² of PCB spaceApplications2.5G/3G Wireless HandsetsDigital Still and Video CamerasHandheld Computers and TerminalsPDA/Smartphones

The DS2781 remains in production, however, for new projects, we recommend ModelGauge m5 MAX17215 fuel gauge.The DS2781 measures voltage, temperature, andcurrent, and estimates available capacity forrechargeable Lithium-Ion and Lithium-Ion Polymerbatteries. Cell stack characteristics and applicationparameters used in the calculations are stored in on-chipEEPROM. The available capacity registersreport a conservative estimate of the amount ofcharge that can be removed given the currenttemperature, discharge rate, stored charge andapplication parameters. Capacity estimation isreported in milliamp hours remaining and percentageof full.ApplicationsCommercial Two-Way RadiosDigital Video CamerasIndustrial PDAs and Handheld PC Data TerminalsPortable GPS Navigation Systems

The DS2788 measures voltage, temperature, and current, and estimates available capacity for rechargeable lithium-ion (Li+) and Li+ polymer batteries. Cell characteristics and application parameters used in the calculations are stored in on-chip EEPROM. The available capacity registers report a conservative estimate of the amount of charge that can be removed given the current temperature, discharge rate, stored charge, and application parameters. Capacity estimation is reported in mAh remaining and percentage of full.LED display drivers and a debounced input make display of the capacity information easy. The LED pins can directly sink current, requiring only a resistor for setting the current in the LED display, thus reducing space andcost.ApplicationsDigital CamerasElectric BicyclesElectric VehiclesPower ToolsUninterruptible Power Supply

The LTC1980 integrates PWM power control for charging a battery and converting the battery voltage to a regulated output or simultaneously charging the battery while powering a system load from an unregulated AC wall adapter. Combining these features into a single IC produces a smaller area and lower cost solution compared to presently available multi-IC solutions. The LTC1980 shares the discrete components for both the battery charger and the DC/DC converter thus minimizing size and cost relative to dual controller solutions. Both the battery charger and DC/DC converter use a current mode flyback topology for high efficiency and excellent transient response. Optional Burst Mode operation and power-down mode allow power density, efficiency and output ripple to be tailored to the application.The LTC1980 provides a complete Li-Ion battery charger with charge termination timer, preset Li-Ion battery voltages, overvoltage and undervoltage protection, and userprogrammable constant-current charging. Automatic battery recharging, shorted-cell detection, and open-drain C/10 and wall plug detect outputs are also provided. User programming allows NiMH and NiCd battery chemistries to be charged as well.Applications Digital Cameras Handheld Computers Personal Digital Assistants 1W to 10W Uninterruptable Power Supplies

The LTC4060 is a complete fast charging system for NiMH or NiCd batteries. Just a few external components are needed to design a standalone linear charging system.An external PNP transistor provides charge current that is user programmable with a resistor. A small external capacitor sets the maximum charge time. No external current sense resistor is needed, and no blocking diode is required.The IC automatically senses the DC input supply and battery insertion or removal. Heavily discharged batteries are initially charged at a C/5 rate before a fast charge is applied. Fast charge is terminated using the –∆V detection method. Backup termination consists of a programmable timer and battery overvoltage detector. An optional external NTC thermistor can be used for temperature-based qualification of charging. An optional programmable recharge feature automatically recharges batteries after discharge.Manual shutdown is accomplished with the SHDN pin, while removing input power automatically puts the LTC4060 into sleep mode. During shutdown or sleep mode, battery drain is <1µA.The LTC4060 is available in both low profile (0.75mm) 16- pin 5mm × 3mm DFN and 16-lead TSSOP packages. Both feature exposed metal die mount pads for optimum thermal performance.Applications Portable Computers, Cellular Phones and PDAs Medical Equipment Charging Docks and Cradles Portable Consumer Electronics

The MAX847 is a complete power-supply and monitoring system for two-way pagers or other low-power digital communications devices. It requires few external components. Included on-chip are: A 1-cell input, 80mA output, synchronous-rectified boost DC-DC regulator with a digitally controlled +1.8V to +4.9V output Three low-noise linear-regulator outputs Three DAC-controlled comparators for software-driven 3-channel A/D conversion SPI™-compatible serial interface Reset and low-battery (LBO) warning outputs Charger for NiCd, NiMH, lithium battery, or storage capacitor for RF PA power or system backup Two 1.8Ω (typical) serial-controlled open-drain MOSFET switchesAn evaluation kit for the MAX847 (MAX847EVKIT) is available to aid in design and prototyping.Applications1-Cell Powered Handheld EquipmentGPS ReceiversTwo-Way Paging

Not Recommended For New Designs. Contact Analog Devices for Potential Replacement.The LTC1559 is a backup battery controller that provides all the functions necessary to implement a backup 3.3V or 5V power supply using a single NiCd cell. It includes a 1.2V to 3.07V/4.63V boost converter, an intelligent 2-stage battery charger, automatic backup switching and a microprocessor reset generator. The boost converter uses a synchronous switching architecture to achieve a typical efficiency of 70%, ensuring maximum backup lifetime from a small NiCd cell. The on-chip NiCd charger uses an internal gas gauge to minimize fast recharge time and prevent overcharging of the backup cell, thereby improving system efficiency and extending the life of the backup cell. The LTC1559 also provides a user programmable trickle charge current to compensate for self-discharge losses in the backup cell. The LTC1559’s automatic backup switching scheme requires minimum intervention from the host system and provides feedback to the host to minimize system loading in the backup state. Its internal VCC fault detector and reset generator eliminate the need for a separate microprocessor supervisory chip in most applications. The LTC1559 is available in an SO-8, 16-pin GN or SO package.Applications Notebook Computers Palmtop Computers/PDAs Portable Instruments Battery-Powered Systems

The LTC4009 is a constant-current/constant-voltage battery charger controller. It uses a synchronous quasiconstant frequency PWM control architecture that will not generate audible noise with ceramic bulk capacitors. Charge current is set by the combination of external sense, input and programming resistors. With no built-in termination, the LTC4009 family charges a wide range of batteries under external control. The LTC4009 features a fully adjustable output voltage, while the LTC4009-1 and LTC4009-2 can be pin-programmed for lithium-ion/polymer battery packs of 1-, 2-, 3- or 4-series cells. The LTC4009-1 provides output voltage of 4.1V/cell, and the LTC4009-2 is a 4.2V/cell version. The device includes AC adapter input current limiting which maximizes the charge rate for a fixed input power level. An external sense resistor programs the input current limit, and the ICL status pin indicates when the battery charge current is being reduced as a result of AC adapter current limiting. The CHRG status pin is active during all charging modes, including special indication for low charge current.Applications Notebook Computers Portable Instruments Battery Backup Systems