Analog Devices Inc./Maxim Integrated

The LTC3868 is a high performance dual step-down switching regulator controller that drives all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phase-lockable frequency of up to 850kHz. Power loss and noise due to the input capacitor ESR are minimized by operating the two controller outputs out of phase.The 170μA no-load quiescent current extends operating life in battery-powered systems. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3868 features a precision 0.8V reference and a power good output indicator. A wide 4V to 24V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries.Independent soft-start pins for each controller ramp the output voltages during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions. The output short-circuit latchoff feature further protects the circuit in short-circuit conditions.For a leaded 28-lead SSOP package with a fixed current limit and one PGOOD output, without phase modulation or a clock output, see the LTC3868-1 data sheet.LTC3868LTC3868-1FeaturesAdjustable Current Limit, Clock Out Pin, Phase Modulation, Two PGOODFixed Current Limit, One PGOODPackageQFN-32SSOP-28ApplicationsNotebook and Palmtop ComputersPortable InstrumentsBattery Operated Digital DevicesDistributed DC Power Systems

The LTC3868-1 is a high performance dual step-down switching regulator controller that drives all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phase-lockable frequency of up to 850kHz. Power loss and noise due to the input capacitor ESR are minimized by operating the two controller outputs out of phase.The 170μA no-load quiescent current extends operating life in battery powered systems. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3868-1 features a precision 0.8V reference and a power good output indicator. A wide 4V to 24V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries.Independent soft-start pins for each controller ramp the output voltages during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions. The output short-circuit latchoff feature further protects the circuit in short-circuit conditions.For a leadless 32-pin QFN package with the additional features of adjustable current limit, clock out, phase modulation and two PGOOD outputs, see the LTC3868 data sheet.LTC3868LTC3868-1FeaturesAdjustable Current Limit, Clock Out Pin, Phase Modulation, Two PGOODFixed Current Limit, One PGOODPackageQFN-32SSOP-28ApplicationsNotebook and Palmtop ComputersPortable InstrumentsBattery Operated Digital DevicesDistributed DC Power Systems

The LTC3871/LTC3871-1 is a high performance bidirectional buck or boost switching regulator controller that operates in either buck or boost mode on demand. It regulates in buck mode from VHIGH-to-VLOWand boost mode from VLOW-to-VHIGHdepending on a control signal, making it ideal for 48V/12V automotive dual battery systems. An accurate current programming loop regulates the maximum current that can be delivered in either direction. The LTC3871/LTC3871-1 allows both batteries to supply energy to the load simultaneously by converting energy from one battery to the other.Its proprietary constant-frequency current mode architecture enhances the signal-to-noise ratio enabling low noise operation and provides excellent current matching between phases. Additional features include discontinuous or continuous mode of operation, OV/UV monitors, independent loop compensation for buck and boost operation, accurate output current monitoring and overcurrent protection. The LTC3871 and LTC3871-1 have different current limit foldback characteristics.ApplicationsAutomotive 48V/12V Dual Battery SystemsBackup Power Systems

The LTC3872-1 is a constant frequency current mode boost DC/DC controller that drives an N-channel power MOSFET and requires very few external components. The No RSENSE™architecture eliminates the need for a sense resistor, improves efficiency and saves board space.The LTC3872-1 provides excellent AC and DC load and line regulation with ±1.5% output voltage accuracy. It incorporates an undervoltage lockout feature that shuts down the device when the input voltage falls below 2.3V.LTC3872-1 has the same functionality as the standard LTC3872 except that it has no frequency foldback in current limit.High switching frequency of 550kHz allows the use of a small inductor. The LTC3872-1 is available in an 8-lead low profile (1mm) ThinSOT™package and 8-pin 2mm × 3mm DFN package.LTC3872LTC3872-1Frequency Foldback In Current LimitYesNoApplicationsTelecom Power Supplies42V Automotive Systems24V Industrial ControlsIP Phone Power Supplies

The LTC3872-1 is a constant frequency current mode boost DC/DC controller that drives an N-channel power MOSFET and requires very few external components. The No RSENSE™architecture eliminates the need for a sense resistor, improves efficiency and saves board space.The LTC3872-1 provides excellent AC and DC load and line regulation with ±1.5% output voltage accuracy. It incorporates an undervoltage lockout feature that shuts down the device when the input voltage falls below 2.3V.LTC3872-1 has the same functionality as the standard LTC3872 except that it has no frequency foldback in current limit.High switching frequency of 550kHz allows the use of a small inductor. The LTC3872-1 is available in an 8-lead low profile (1mm) ThinSOT™package and 8-pin 2mm × 3mm DFN package.LTC3872LTC3872-1Frequency Foldback In Current LimitYesNoApplicationsTelecom Power Supplies42V Automotive Systems24V Industrial ControlsIP Phone Power Supplies

The LTC3873 is a constant frequency, current mode, boost, flyback or SEPIC DC/DC controller that drives an N-channel power MOSFET in high input and output voltage converter applications. Soft-start can be programmed using an external capacitor.The LTC3873 provides ±1.5% output voltage accuracy and consumes only 300μA quiescent current during normal operation and only 55μA during micropower start-up. Using a 9.3V internal shunt regulator, the LTC3873 can be powered from a high input voltage through a resistor or it can be powered directly from a low impedance DC voltage of 9V or less.The LTC3873 is available in 8-lead ThinSOT and 2mm x 3mm DFN packages.LTC3873LTC3873-5VCCUV+8.4V4.1VVCCUV–4V2.9VAPPLICATIONSTelecom Power Supplies42V and 12V Automotive Power SuppliesPortable Electronic Equipment