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 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

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 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 DS2775–DS2778 report available capacity for rechargeable lithium-ion (Li+) and Li+ polymer (Li-Poly) batteries in mAh and as a percentage of full. Safe operation is ensured by the integrated Li+ protector. The DS2776/DS2778 support SHA-1-based challenge-response authentication in addition to all other DS2775/DS2777 features.Precision measurements of voltage, temperature, and current, along with a cell characteristics table and application parameters, are used for capacity estimation calculations. The 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.The DS2775–DS2778 operate from +4.0V to +9.2V for direct integration into battery packs with two Li+ or Li- Poly cells.In addition to nonvolatile storage for cell compensation and application parameters, the DS2775–DS2778 offer 16 bytes of EEPROM for use by the host system and/or pack manufacturer to store battery lot and date tracking information. The EEPROM can also be used for nonvolatile storage of system and/or battery usage statistics. A Maxim 1-Wire® (DS2775/DS2776) or 2-wire (DS2777/DS2778) interface provides serial communication to access measurement and capacity data registers, control registers, and user memory. The DS2776/DS2778 use the SHA-1 hash algorithm in a challenge-response pack authentication protocol for battery-pack verification.ApplicationsDigital Still, Video, and Action CamerasHandheld Computers and TerminalsHandheld RadiosHealth and Fitness MonitorsHome and Building Automation, SensorsMedical DevicesPower ToolsSmart Batteries

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 MAX16023/MAX16024 low-power battery-backup circuits with a regulated output are capable of delivering up to 100mA output current. The MAX16023/MAX16024 include a low-dropout regulator, a microprocessor (µP) reset circuit, and a battery switchover circuit. Additional available features include a manual reset, a power-fail comparator, and a battery-on indicator. These devices reduce the number of external components to minimize board space and improve reliability.The MAX16023/MAX16024 are ideally suited for providing power for backing up critical memory such as static random-access memory (SRAM) or real-time clocks (RTCs). The regulated output is powered by VCC when it is present and switches over to the backup power during brownout. The MAX16023/MAX16024 accept an input voltage from 1.53V to 5.5V and provide fixed standard output voltages of 1.2V, 1.8V, 2.5V, 3.0V, and 3.3V. The MAX16024 offers the ability to externally set the output voltage using a resistive divider. All outputs are available with push-pull or open-drain configurations.The MAX16023 offers a power-fail comparator for monitoring an additional voltage or for providing an early power-fail warning. Another feature includes a manual-reset input (MAX16023/MAX16024). The MAX16024 also features a battery-on indicator and chip-enable gating function.The MAX16023/MAX16024 are offered in 8- and 10-pin TDFN packages and are fully specified from -40°C to +85°C temperature range.ApplicationsGPS SystemsIndustrial ControlsMain/Backup Power for RTCs/SRAMPoint-of-Sale EquipmentPortable/Battery EquipmentSet-Top Boxes

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

The LTC6804 is a 3rd generation multicell battery stack monitor that measures up to 12 series connected battery cells with a total measurement error of less than 1.2mV. The cell measurement range of 0V to 5V makes the LTC6804 suitable for most battery chemistries. All 12 cell voltages can be captured in 290μs, and lower data acquisition rates can be selected for high noise reduction.Multiple LTC6804 devices can be connected in series, permitting simultaneous cell monitoring of long, high voltage battery strings. Each LTC6804 has an isoSPI interface for high speed, RF-immune, local area communications. Using the LTC6804-1, multiple devices are connected in a daisy-chain with one host processor connection for all devices. Using the LTC6804-2, multiple devices are connected in parallel to the host processor, with each device individually addressed.Additional features include passive balancing for each cell, an onboard 5V regulator, and 5 general purpose I/O lines. In sleep mode, current consumption is reduced to 4μA. The LTC6804 can be powered directly from the battery, or from an isolated supply.Applications Electric and Hybrid Electric Vehicles Backup Battery Systems Grid Energy Storage High Power Portable Equipment

The MAX77751 is a standalone, 3.15A charger with integrated USB Type-C® CC detection and reverse boost capability. The fast-charge current and top-off current thresholds are easily configured with resistors. The MAX77751 operates with an input voltage of 4.5V to 13.7V and has a maximum input current limit of 3A. The IC also implements the adaptive input current limit (AICL) function that regulates the input voltage by reducing input current, to prevent the voltage of a weak adapter from collapsing or folding back.The USB Type-C Configuration Channel (CC) detection pins on the MAX77751 enable automatic USB Type-C power source detection and input current limit configuration. To support a variety of legacy USB as well as proprietary adapters, the IC also integrates BC1.2 detection using the D+ and D- pins. The IC runs the CC detection and BC1.2 detection automatically without any software as soon as the USB plug is inserted.The IC also offers Reverse-Boost capability up to 5.1V, 1.5A, which can be enabled with the ENBST pin. The STAT pin indicates charging status, while the INOKB pin indicates valid input voltage. Charging can be stopped by pulling the ITOPOFF pin low.The MAX77751 is equipped with a Smart Power Selector™ and a battery true-disconnect FET to control the charging and discharging of the battery or isolate the battery in case of a fault. The MAX77751 is offered in several variants to support Li-ion batteries with various termination voltages from 4.1V to 4.5V. The IC comes in a 3mm x 3mm, 0.4mm pitch 24-lead FC2QFN package making it suitable for low-cost PCB assembly.ApplicationsMobile Point-of-Sale (mPOS) TerminalsPortable Medical DevicesWireless HeadphonesGPS TrackersCharging Cradles for Wearable DevicesPower BanksMobile Routers