Analog Devices

The LTC3408 is a high efficiency monolithic synchronous buck regulator optimized for WCDMA power amplifier applications. The output voltage can be dynamically programmed from 0.3V to 3.5V. At VOUT> 3.6V an internal 0.08Ω bypass P-channel MOSFET connects VOUTdirectly to VIN, eliminating power loss through the inductor.The input voltage range is 2.5V to 5V making the LTC3408 ideally suited for single Li-Ion battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems.Switching frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors and capacitors. The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode.The LTC3408 is available in a low profile (0.75mm) 8-lead 3mm × 3mm DFN package.ApplicationsWCDMA Cell Phone Power AmplifiersWireless Modems

The LTC3409A is a high efficiency, monolithic synchronous buck regulator using a constant frequency, current mode architecture. The LTC3409A improves upon the LTC3409’s light load regulation in Burst Mode operation. The output voltage is adjusted via an external resistor divider.Fixed switching frequencies of 1.7MHz and 2.6MHz are supported. Alternatively, an internal PLL will synchronize to an external clock in the frequency range of 1MHz to 3MHz. This range of switching frequencies allows the use of small surface mount inductors and capacitors, including ceramics.Supply current during Burst Mode operation is only 65μA dropping to <1μA in shutdown. The 1.6V to 5.5V input voltage range makes the LTC3409A ideally suited for single cell Li-Ion, Li-Metal and 2-cell alkaline, NiCd or NiMH battery-powered applications. 100% duty cycle capability provides low dropout operation, extending battery life in portable systems. Burst Mode operation can be user-enabled, increasing efficiency at light loads, further extending battery life.The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. Internal soft-start offers controlled output voltage rise time at startup without the need for external components.VREFToleranceLTC3409VREFToleranceLTC3409A±3%ApplicationsCellular PhonesDigital CamerasMP3 Players

The LTC3410B is a high efficiency monolithic synchronous buck regulator using a constant frequency, current mode architecture. The device is available in adjustable and fixed output voltage versions. Supply current during operation is only 200µA, dropping to <1µA in shutdown. The 2.5V to 5.5V input voltage range makes the LTC3410B ideally suited for single Li-Ion battery-powered applications.100% duty cycle provides low dropout operation, extending battery life in portable systems. PWM pulse skipping mode operation provides very low output ripple voltage for noise sensitive applications.Switching frequency is internally set at 2.25MHz, allowing the use of small surface mount inductors and capacitors. The LTC3410B is specifically designed to work well with ceramic output capacitors, achieving very low output voltage ripple and a small PCB footprint.The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. Low output voltages are easily supported with the 0.8V feedback reference voltage. The LTC3410B is available in a tiny, low profile SC70 package.VoutBurst ModeLTC3410Adj. Down To 0.8VYesLTC3410BAdj. Down To 0.8VNoLTC3410-1.875Fixed 1.875VYesApplicationsCellular TelephonesPersonal Information AppliancesWireless and DSL ModemsDigital Still CamerasMP3 PlayersPortable Instruments

The LTC3411A is a constant frequency, synchronous step-down DC/DC converter. Intended for medium power applications, it operates from a 2.5V to 5.5V input voltage range and has a user configurable operating frequency up to 4MHz, allowing the use of tiny, low cost capacitors and inductors 1mm or less in height. The output voltage is adjustable from 0.8V to 5.5V. Internal synchronous power switches provide high efficiency. The LTC3411A’s current mode architecture and external compensation allow the transient response to be optimized over a wide range of loads and output capacitors.The LTC3411A can be configured for automatic power saving Burst Mode operation (IQ= 40µA) to reduce gate charge losses when the load current drops below the level required for continuous operation. For reduced noise and RF interference, the SYNC/MODE pin can be configured to skip pulses or provide forced continuous operation.To further maximize battery life, the P-channel MOSFET is turned on continuously in dropout (100% duty cycle). In shutdown, the device draws <1µA.ApplicationsNotebook ComputersDigital CamerasCellular PhonesHandheld InstrumentsBoard Mounted Power Supplies

The LTC3412A is a high efficiency monolithic synchronous, step-down DC/DC converter utilizing a constant frequency, current mode architecture. It operates from an input voltage range of 2.25V to 5.5V and provides a regulated output voltage from 0.8V to 5V while delivering up to 3A of output current. The internal synchronous power switch with 77mΩ on-resistance increases efficiency and eliminates the need for an external Schottky diode. Switching frequency is set by an external resistor or can be synchronized to an external clock. 100% duty cycle provides low dropout operation extending battery life in portable systems. OPTI-LOOP®compensation allows the transient response to be optimized over a wide range of loads and output capacitors.The LTC3412A can be configured for either Burst Mode operation or forced continuous operation. Forced continuous operation reduces noise and RF interference while Burst Mode operation provides high efficiency by reducing gate charge losses at light loads. In Burst Mode operation, external control of the burst clamp level allows the output voltage ripple to be adjusted according to the application requirements.APPLICATIONSPoint-of-Load RegulationNotebook ComputersPortable InstrumentsDistributed Power Systems

The LTC3413 is a high efficiency monolithic synchronous step-down DC/DC converter utilizing a constant frequency, current mode architecture. It operates from an input voltage range of 2.25V to 5.5V and provides a regulated output voltage equal to (0.5)VREFwhile sourcing or sinking up to 3A of output current. An internal voltage divider reduces component count and eliminates the need for external resistors by dividing the reference voltage in half. The internal synchronous power switch with 85mΩ on-resistance increases efficiency and eliminates the need for an external Schottky diode. Switching frequencies up to 2MHz are set by an external resistor.Forced-continuous operation in the LTC3413 reduces noise and RF interference. Fault protection is provided by an overcurrent comparator that limits output current during both sourcing and sinking operations. Adjustable compensation allows the transient response to be optimized over a wide range of loads and output capacitors.ApplicationsBus Termination: DDR and QDR™Memory, SSTL, HSTL, ...Notebook ComputersDistributed Power Systems

The LTC3414 is a high efficiency monolithic synchronous, step-down DC/DC converter utilizing a constant frequency, current mode architecture. It operates from an input voltage range of 2.25V to 5.5V and provides a regulated output voltage from 0.8V to 5V while delivering up to 4A of output current. The internal synchronous power switch with 67mΩ on-resistance increases efficiency and eliminates the need for an external Schottky diode. Switching frequency is set by an external resistor or can be synchronized to an external clock. 100% duty cycle provides low dropout operation extending battery life in portable systems. OPTI-LOOP®compensation allows the transient response to be optimized over a wide range of loads and output capacitors.The LTC3414 can be configured for either Burst Mode operation or forced continuous operation. Forced continuous operation reduces noise and RF interference while Burst Mode operation provides high efficiency by reducing gate charge losses at light loads. In Burst Mode operation, external control of the burst clamp level allows the output voltage ripple to be adjusted according to the requirements of the application.ApplicationsPoint-of-Load RegulationNotebook ComputersPortable InstrumentsDistributed Power Systems

The LTC3415 is a high efficiency, monolithic synchronous buck regulator using a phase lockable constant frequency, current mode architecture. PolyPhase®operation allows multiple LTC3415s to run out of phase while using minimal input and output capacitance. The operating supply range is from 5.5V down to 2.5V, making it suitable for single Lithium-Ion battery as well as point of load power supply applications. Burst Mode operation provides high efficiency at low load currents. 100% duty cycle provides low dropout operation that extends operating time in battery-operated systems.The operating frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors. For switching-noise sensitive applications, it can be externally synchronized from 0.75MHz to 2.25MHz. The PHMODE pin allows user control of the phase of the outgoing clock signal. The current sense comparator is factory trimmed for accurate output current sharing. Burst Mode operation is inhibited during synchronization or when the MODE pin is pulled low to reduce noise and RF interference.ApplicationsPoint of Load Power SupplyPortable InstrumentsDistributed Power SystemsBattery-Powered Equipment

The LTC3417A-1 is a dual constant frequency, synchronous step-down DC/DC converter. Intended for medium power applications, it operates from a 2.25V to 5.5V input voltage range and has a constant programmable switching frequency, allowing the use of tiny, low cost capacitors and inductors 2mm or less in height. Each output voltage is adjustable from 0.8V to 5V. Internal synchronous, low RDS(ON)power switches provide high efficiency without the need for external Schottky diodes.The open drainPORpin goes low when either output voltage falls 6% below regulation. The output will remain low 150ms longer than the duration of the out of regulation condition.A user selectable mode input allows the user to trade off ripple voltage for light load efficiency. Burst Mode operation provides high efficiency at light loads, while pulse skip mode provides low ripple noise at light loads. A phase mode pin allows the second channel to operate in-phase or 180° out-of-phase with respect to channel 1. Out-of-phase operation produces lower RMS current on VINand thus lower stress on the input capacitor.To further maximize battery life, the P-channel MOSFETs are turned on continuously in dropout (100% duty cycle) and both channels draw a total quiescent current of only 100μA. In shutdown, the device draws <1μA.FeaturesNotesLTC3417--LTC3417AImproved Channel Matching-LTC3417A-1Power On ResetRecommended For New DesignsLTC3417A-2Power GoodRecommended For New DesignsApplicationsGPS/Navigation SystemsAutomotive InstrumentationPC CardsIndustrial Power SuppliesGeneral Purpose Point of Load DC/DC

The LTC3418 is a high efficiency, monolithic synchronous step-down DC/DC converter utilizing a constant frequency, current mode architecture. It operates from an input voltage range of 2.25V to 5.5V and provides a regulated output voltage from 0.8V to 5V while delivering up to 8A of output current. The internal synchronous power switch increases efficiency and eliminates the need for an external Schottky diode. Switching frequency is set by an external resistor or can be synchronized to an external clock. OPTI-LOOP®compensation allows the transient response to be optimized over a wide range of loads and output capacitors.The LTC3418 can be configured for either Burst Mode operation or forced continuous operation. Forced continuous operation reduces noise and RF interference while Burst Mode operation provides high efficiency by reducing gate charge losses at light loads. In Burst Mode operation, external control of the burst clamp level allows the output voltage ripple to be adjusted according to the requirements of the application. A tracking input in the LTC3418 allows for proper sequencing with respect to another power supply.ApplicationsMicroprocessor, DSP and Memory SuppliesDistributed 2.5V, 3.3V and 5V Power SystemsAutomotive ApplicationsPoint of Load RegulationNotebook Computers