Analog Devices

The LT3645 is a dual output regulator combining a 500mA buck regulator and a 200mA low dropout linear regulator (LDO). The wide input voltage range of 3.6V to 36V makes the LT3645 suitable for regulating power from a wide variety of sources, including 24V industrial supplies and automotive batteries. Its high operating frequency allows the use of tiny, low cost inductors and capacitors, resulting in a very small solution.Cycle-by-cycle current limit and frequency foldback provide protection against shorted outputs. Soft-start and frequency foldback eliminate input current surge during start-up.The linear regulator operates from the VCC2pin at voltages down to 1.2V. It supplies 200mA of output current with a typical dropout voltage of 310mV.Other features of the LT3645 include a <2μA shutdown, short circuit protection, soft-start and thermal shutdown. The LT3645 is available in the thermally enhanced 16-lead (3mm × 3mm) QFN package, or a 12-lead MSE package.ApplicationsAutomotive CMOS Image SensorsIndustrial/Automotive Micro-Controller Supply

The LT3650 is a complete monolithic single-cell Li-Ion/Polymer battery charger that operates over a 4.75V to 32V input voltage range (7.5V minimum start-up voltage). The LT3650 provides a constant-current/constant-voltage charge characteristic, with maximum charge current externally programmable up to 2A, set using an external current sense resistor. A precondition feature trickle charges a low voltage battery, and bad-battery detection provides a signal and suspends charging if a battery does not respond to preconditioning.The LT3650 can be configured to terminate charging when charge current falls to C/10, or one-tenth the programmed maximum current. Once charging is terminated, the LT3650 enters a low current (85μA) standby mode. An auto-restart feature starts a new charging cycle if the battery voltage drops 2.5% from the fl oat voltage, or if a new battery is inserted into a charging system.The LT3650 contains a user-programmable internal safety timer (typically set to a three hour full cycle time). The IC can be configured to use this internal timer if a time-based termination scheme is desired in which charging can continue below C/10 until a desired time is reached.The LT3650 is available in a low profile (0.75mm) 3mm × 3mm 12-pin DFN and 12-pin MSOP packages.Float VoltageLT3650-4.14.1VLT3650-4.24.2VLT3650-8.28.2VLT3650-8.48.4VApplicationsIndustrial Handheld Instruments12V to 24V Automotive and Heavy EquipmentDesktop Cradle ChargersNotebook Computers

The LT3650 is a complete monolithic single-cell Li-Ion/Polymer battery charger that operates over a 4.75V to 32V input voltage range (7.5V minimum start-up voltage). The LT3650 provides a constant-current/constant-voltage charge characteristic, with maximum charge current externally programmable up to 2A, set using an external current sense resistor. A precondition feature trickle charges a low voltage battery, and bad-battery detection provides a signal and suspends charging if a battery does not respond to preconditioning.The LT3650 can be configured to terminate charging when charge current falls to C/10, or one-tenth the programmed maximum current. Once charging is terminated, the LT3650 enters a low current (85μA) standby mode. An auto-restart feature starts a new charging cycle if the battery voltage drops 2.5% from the fl oat voltage, or if a new battery is inserted into a charging system.The LT3650 contains a user-programmable internal safety timer (typically set to a three hour full cycle time). The IC can be configured to use this internal timer if a time-based termination scheme is desired in which charging can continue below C/10 until a desired time is reached.The LT3650 is available in a low profile (0.75mm) 3mm × 3mm 12-pin DFN and 12-pin MSOP packages.Float VoltageLT3650-4.14.1VLT3650-4.24.2VLT3650-8.28.2VLT3650-8.48.4VApplicationsIndustrial Handheld Instruments12V to 24V Automotive and Heavy EquipmentDesktop Cradle ChargersNotebook Computers

The LT3651-8.2/LT3651-8.4 are 2-cell, 4A Li-Ion/Polymer battery chargers that operate over a 9V to 32V input voltage range. An efficient monolithic average current mode synchronous switching regulator provides constant current, constant voltage charging with programmable maximum charge current. A charging cycle starts with battery insertion or when the battery voltage drops 2.5% below the float voltage. Charger termination is selectable as either charge current or internal safety timer timeout. Charge current termination occurs when the charge current falls to one-tenth the programmed maximum current (C/10). Timer based termination is typically set to three hours and is user programmable (charging continues below C/10 until timeout). Once charging is terminated, the LT3651-8.2/LT3651-8.4 supply current drops to 85μA into a standby mode.The LT3651-8.2/LT3651-8.4 offer several safety features. A discharged battery is preconditioned with a small trickle charge and generates a signal if unresponsive. A thermistor monitors battery temperature, halting charging if out of range. Excessive die temperature reduces charge current. Charge current is also reduced to maintain constant input current to prevent excessive input loading. The LT3651-8.2/LT3651-8.4 are available in a 5mm × 6mm 36-lead QFN package.Float VoltageLT3651-4.14.1VLT3651-4.24.2VLT3651-8.28.2VLT3651-8.48.4VApplicationsIndustrial Handheld Instruments12V to 24V Automotive and Heavy EquipmentDesktop Cradle ChargersNotebook Computers

The LT3652HV is a complete monolithic step-down battery charger that operates over a 4.95V to 34V input range. The LT3652HV provides a constant-current/constant-voltage charge characteristic, with maximum charge current externally programmable up to 2A. The charger employs a 3.3V float voltage feedback reference, so any desired battery float voltage up to 18V can be programmed with a resistor divider.The LT3652HV employs an input voltage regulation loop, which reduces charge current if the input voltage falls below a programmed level, set with a resistor divider. When the LT3652HV is powered by a solar panel, the input regulation loop is used to maintain the panel at peak output power.The LT3652HV can be configured to terminate charging when charge current falls below 1/10 of the programmed maximum (C/10). Once charging is terminated, the LT3652HV enters a low-current (85μA) standby mode. An auto-recharge feature starts a new charging cycle if the battery voltage falls 2.5% below the programmed fl oat voltage. The LT3652HV also contains a programmable safety timer, used to terminate charging after a desired time is reached. This allows top-off charging at currents less than C/10.Vin MaxVfloat MaxFeaturesLT365232V14.4Vinternal reverse blockingVbat<4.2VLT3652HV34V18VApplicationsSolar Powered ApplicationsRemote Monitoring StationsPortable Handheld Instruments12V to 24V Automotive SystemsBattery Charging from Current Limited Adapter

The LT3653 is a monolithic current mode PWM step-down regulator with programmable output current limit. Typically, it is used with battery charger power path controllers to pre-regulate the output and optimize the battery charger efficiency. Output current limit provides accurate control over system power dissipation.The wide operating input voltage range of 7.5V to 30V suits the LT3653 to a variety of input sources, including unregulated 12V wall adapters, 24V industrial supplies, Firewire and automotive power. Input overvoltage protection allows the LT3653 to handle 60V input transients.The LT3653 control pin, VC, is available for external battery tracking control, Bat-Track. The LT3653 will block output discharge during an open or shorted input.The HVOK pin indicates that the internal bias supplies are present and no faults have occurred (i.e., overtemperature and input overvoltage and undervoltage). The LT3653 includes a 1.5MHz frequency oscillator, internal compensation, and an internal boost diode to minimize the number of external components. The LT3653 is available in an 8-lead (2mm × 3mm) package with exposed pads for low thermal resistance.ApplicationsBattery Powered EquipmentPortable USB Devices – Cameras, MP3 Players, PDAsAutomotive Battery RegulationMultiple-Source Battery Chargers

The LT3667 is a monolithic triple power supply composed of a 400mA buck switching regulator and two 200mA low dropout linear regulators (LDOs).The buck regulator includes a high efficiency switch, a boost diode, and the necessary oscillator, control and logic circuitry. Current mode topology is used for fast transient response and good loop stability. Low ripple Burst Mode operation maintains high efficiency at low output currents while keeping output ripple below 15mV in a typical application.Each LDO supplies 200mA of output current with a typical dropout voltage of 340mV, and each LDO has an accurate resistor programmable current limit.Internal protection circuitry includes reverse-battery protection, current limiting, thermal limiting and reverse current protection.The LT3667 is available in a thermally-enhanced 16-Lead MSOP and a 24-Pin 3mm x 5mm QFN package with exposed pad for low thermal resistance.ApplicationsAutomotive Battery RegulationPower for Portable InstrumentationIndustrial SuppliesFault-Protected Sensor Supply

The LT3668 is a monolithic triple power supply composed of a 400mA buck switching regulator and two 200mA low dropout linear tracking regulators (LDOs).This provides a complete and robust power solution for applications that require the power supply of a sensor to tightly track the power supply of a measurement ASIC.Each tracking LDO supplies 200mA of output current with a typical dropout voltage of 340mV, and each LDO has an accurate resistor programmable current limit.Internal protection circuitry includes reverse-battery protection, current limiting, thermal limiting and reverse current protection.The buck regulator includes a high efficiency switch, a boost diode, and the necessary oscillator, control and logic circuitry. Current mode topology is used for fast transient response and good loop stability. Low ripple Burst Mode operation maintains high efficiency at low output currents while keeping output ripple below 15mV in a typical application.The LT3668 is available in a thermally-enhanced 16-lead MSOP package with exposed pad for low thermal resistance.ApplicationsFault-Protected Sensor SupplyAutomotive and Industrial SuppliesPower for Portable Instrumentation

The LT3669 is an industrial transceiver that includes a step-down switching regulator and a low dropout linear regulator. Wake-up detect functionality, as well as a programmable power-on reset timer are also included. The current limit and slew rate of the transmitters are externally adjustable for optimum EMC performance.The line drivers can source/sink up to 250mA of current each or 500mA when connected together, with a minimal residual voltage of less than 2.1V. An internal adaptive pulsing scheme allows the drivers to safely switch heavy capacitive loads and incandescent bulbs. Thermal shutdown provides additional protection. Line protection of ±60V in the line interface pins allows the use of standard TVS diodes with L+ operating voltages up to 40V.The switching regulator integrates the catch diode in LT3669 (up to 100mA load current) and requires an external catch diode in LT3669-2 (up to 300mA load current).The LT3669 implements an IO-Link device PHY. For IO-Link master designs, see the LTC2874.ApplicationsIndustrial Sensors and Actuators