Analog Devices

The LT3383 is a complete power management solution for advanced portable application processor-based systems. The device contains four synchronous step-down DC/DC converters for core, memory, I/O, and system on-chip (SoC) rails and three 300mA LDO regulators for low noise analog supplies.Regulator start-up is sequenced by connecting outputs to enable pins in the desired order. A master power-on pin is provided to initiate pin-strapped power-on sequences.A status pin is available to indicate regulator undervoltages. If an overtemperature or low supply fault is detected all regulators are disabled during the fault condition.The device is available in a 40-lead 6mm × 6mm QFN with wettable flanks for optical inspection.APPLICATIONSAutomotiveIndustrialCommunicationsGeneral Purpose Multichannel Power Supplies

The LT3420/LT3420-1 charge high voltage photoflash capacitors quickly and efficiently. Designed for use in both digital and film cameras, these devices use a flyback topology to achieve efficiencies up to four times better than competing flash modules. A unique adaptive off-time control algorithm* maintains current-limited continuous mode transformer operation throughout the entire charge cycle, eliminating the high inrush current often found in modules.The LT3420/LT3420-1 output voltage sensing scheme* monitors the flyback voltage to indirectly regulate the output voltage, eliminating an output resistor divider or discrete zener diode. This feature allows the capacitor to be held at a fully charged state without excessive power consumption. Automatic refresh (which can be defeated) allows the capacitor to remain charged while consuming an average input current of about 2mA, at a user-defined refresh rate. A logic high on the CHARGE pin initiates charging, while the DONE pin signals that the capacitor is fully charged.The LT3420/LT3420-1 are available in 10-Lead MSOP and (3mm × 3mm) DFN packages.*Protected by U.S. Patents including 6518733.ApplicationsDigital Camera Flash UnitFilm Camera Flash UnitHigh Voltage Power Supplies

The LT3430/LT3430-1 are monolithic buck switching regulators that accept input voltages up to 60V. A high efficiency 3A, 0.1Ω switch is included on the die along with all the necessary oscillator, control and logic circuitry. A current mode architecture provides fast transient response and excellent loop stability.Special design techniques and a new high voltage process achieve high efficiency over a wide input range. Efficiency is maintained over a wide output current range by using the output to bias the circuitry and by utilizing a supply boost capacitor to saturate the power switch. Patented circuitry* maintains peak switch current over the full duty cycle range. A shutdown pin reduces supply current to 30µA and a SYNC pin can be externally synchronized with a logic level input from 228kHz to 700kHz for the LT3430 or from 125kHz to 250kHz for the LT3430-1.The LT3430/LT3430-1 are available in a thermally enhanced 16-pin TSSOP package.ApplicationsIndustrial and Automotive Power SuppliesPortable ComputersBattery ChargersDistributed Power Systems

The LT3433 is a 200kHz fixed-frequency current mode switching regulator that provides both step-up and stepdown regulation using a single inductor. The IC operates over a 4V to 60V input voltage range making it suitable for use in various wide input voltage range applications such as automotive electronics that must withstand both load dump and cold crank conditions.Internal control circuitry monitors system conditions and converts from single switch buck operation to dual switch bridged operation when required, seamlessly changing between step-down and step-up voltage conversion.Optional Burst Mode®operation reduces no-load quiescent current to 100µA and maintains high efficiencies with light loads.Current limit foldback and frequency foldback help prevent inductor current runaway during start-up. Programmable soft-start helps prevent output overshoot at start-up.The LT3433 is available in a 16-lead thermally enhanced TSSOP package.Applications12V Automotive SystemsWall Adapter Powered SystemsBattery Power Voltage Buffering

The LT3435 is a 500kHz monolithic buck switching regulator that accepts input voltages up to 60V. A high efficiency 3A, 0.1Ω switch is included on the die along with all the necessary oscillator, control and logic circuitry. Current mode topology is used for fast transient response and good loop stability.Innovative design techniques along with a new high voltage process achieve high efficiency over a wide input range. Efficiency is maintained over a wide output current range by employing Burst Mode operation at low currents, utilizing the output to bias the internal circuitry, and by using a supply boost capacitor to fully saturate the power switch. Patented circuitry maintains peak switch current over the full duty cycle range.* Shutdown reduces input supply current to less than 1µA. External synchronization can be implemented by driving the SYNC pin with logic-level inputs. A single capacitor from the CSS pin to the output provides a controlled output voltage ramp (soft-start). The device also has a power good flag with a programmable threshold and time-out and thermal shutdown protection.The LT3435 is available in a 16-pin TSSOP package with an exposed pad leadframe for low thermal resistance.ApplicationsHigh Voltage Power Conversion14V and 42V Automotive SystemsIndustrial Power SystemsDistributed Power SystemsBattery-Powered SystemsUSB Powered Systems

The LT3436 is an 800kHz monolithic boost switching regulator. A high efficiency 3A, 0.1Ω switch is included on the die together with all the control circuitry required to complete a high frequency, current-mode switching regulator. Current-mode control provides fast transient response and excellent loop stability.New design techniques achieve high efficiency at high switching frequencies over a wide operating range. A low dropout internal regulator maintains consistent performance over a wide range of inputs from 24V systems to Li- Ion batteries. An operating supply current of 1mA maintains high efficiency, especially at lower output currents. Shutdown reduces quiescent current to 11µA. Maximum switch current remains constant at all duty cycles. Synchronization capability allows an external logic level signal to increase the internal oscillator from 1MHz to 1.4MHz.Full cycle-by-cycle switch current limit protection and thermal shutdown are provided. High frequency operation allows the reduction of input and output filtering components and permits the use of tiny chip inductors. The LT3436 is available in an exposed pad, 16-pin TSSOP package.*Patent numbers 6,535,042; 6,611,131; 6,498,466ApplicationsDSL ModemsPortable ComputersBattery-Powered SystemsDistributed Power

The LT3437 is a 200kHz monolithic buck switching regulator that accepts input voltages up to 80V. A high efficiency 500mA, 0.8Ω switch is included on the die along with all the necessary oscillator, control and logic circuitry. Current mode topology is used for fast transient response and good loop stability.Innovative design techniques along with a new high voltage process achieve high efficiency over a wide input range. Efficiency is maintained over a wide output current range by employing Burst Mode operation at low currents, utilizing the output to bias the internal circuitry, and by using a supply boost capacitor to fully saturate the power switch. Burst Mode operation can be defeated by a logic high signal on the SYNC pin which results in lower light load ripple at the expense of light load efficiency. Patented circuitry maintains peak switch current over the full duty cycle range*. Shutdown reduces input supply current to less than 1µA. External synchronization can be implemented by driving the SYNC pin with logic-level inputs. A single capacitor from the CSSpin to the output provides a controlled output voltage ramp (soft-start).The LT3437 is available in a low profile (0.75mm) 3mm × 3mm 10-pin DFN package or a 16-Pin TSSOP Package both with exposed pad leadframes for low thermal resistance.*Protected by U.S. Patents including 6498466.ApplicationsHigh Voltage Power Conversion14V and 42V Automotive SystemsIndustrial Power SystemsDistributed Power SystemsBattery-Powered SystemsPowered Ethernet

The LT3439 is a push-pull DC/DC transformer driver that reduces conducted and radiated electromagnetic interference (EMI). Ultralow noise and EMI are achieved by controlling the output switch voltage and current slew rates. Slew rates are user adjustable to optimize output noise versus efficiency. The LT3439 can reduce high frequency harmonic content by as much as 40dB with only a minor decrease in efficiency.The LT3439 includes two 1A current limited power switches to ensure start-up under heavy loads. It also includes an oscillator that can be synchronized to an external clock for more accurate placement of switcher harmonics. Protection features include current limiting, undervoltage lockout, thermal shutdown and cross conduction prevention circuitry.The LT3439 is available in a thermally enhanced 16-pin TSSOP with an exposed backside.ApplicationsLow Noise Isolated SuppliesRadio and Telecom SuppliesDistributed SuppliesMedical InstrumentsPrecision InstrumentsLow Noise Filament Supplies

The LT3460/LT3460-1 are general purpose step-up DC/DC converters. The LT3460/LT3460-1 switch at 1.3MHz/ 650KHz, allowing the use of tiny, low cost and low height capacitors and inductors. The constant frequency results in low, predictable output noise that is easy to filter.The high voltage switches in the LT3460/LT3460-1 are rated at 38V, making the device ideal for boost converters up to 36V. The LT3460 can generate 12V at up to 70mA from a 5V supply.The low 1mA quiescent current and 650kHz switching frequency of LT3460-1 make it ideal for lower current applications.The LT3460 is available in SC70 and SOT-23 packages. The LT3460-1 is available in SC70 and 2mm × 2mm DFN packages.ApplicationsDigital CamerasCCD Bias SupplyXDSL Power SupplyTFT-LCD Bias SupplyLocal 5V or 12V SupplyMedical Diagnostic EquipmentBattery Backup

The LT3461/LT3461A are general purpose fixed frequency current mode step-up DC/DC converters. Both devices feature an integrated Schottky and a low VCESATswitch allowing a small converter footprint and lower parts cost. The LT3461 switches at 1.3MHz while the LT3461A switches at 3MHz. These high switching frequencies enable the use of tiny, low cost and low height capacitors and inductors. The constant switching frequency results in predictable output noise that is easy to filter, and the inductor based topology ensures an input free from switching noise typically present with charge pump solutions. The high voltage switch in the LT3461/LT3461A is rated at 40V making the device ideal for boost converters up to 38V.The LT3461/LT3461A are available in a low profile (1mm) SOT-23 package.Switching FrequencyLT34611.3MHzLT3461A3MHzApplicationsDigital CamerasCCD Bias SupplyXDSL Power SupplyTFT-LCD Bias SupplyLocal 5V or 12V SupplyMedical Diagnostic EquipmentBattery Backup