Analog Devices

The LTC3642 is a high efficiency, high voltage step-down DC/DC converter with internal high side and synchronous power switches that draws only 12μA typical DC supply current at no load while maintaining output voltage regulation.The LTC3642 can supply up to 50mA load current and features a programmable peak current limit that provides a simple method for optimizing efficiency in lower current applications. The LTC3642’s combination of Burst Mode®operation, integrated power switches, low quiescent current, and programmable peak current limit provides high efficiency over a broad range of load currents.With its wide 4.5V to 45V input range and internal overvoltage monitor capable of protecting the part through 60V surges, the LTC3642 is a robust converter suited for regulating a wide variety of power sources. Additionally, the LTC3642 includes a precise run threshold and soft-start feature to guarantee that the power system start-up is well-controlled in any environment.The LTC3642 is available in the thermally enhanced 3mm × 3mm DFN and MS8E packages.Applications4mA to 20mA Current LoopsIndustrial Control SuppliesDistributed Power SystemsPortable InstrumentsBattery-Operated DevicesAutomotive Power Systems

The LTC3643 is a bidirectional synchronous step-up charger and step-down converter which efficiently charges a capacitor array up to 40V from an input supply between 3V to 17V. When the input supply falls below the programmable power-fail threshold, the step-up charger operates in reverse as a synchronous step-down regulator to power the system rail from the backup capacitor during this power interuption/failure condition.When charging the backup capacitor, an external low-value sense resistor may be used to maintain an accurate current limit from the input supply or implement PowerPath™functionality.The step-down converter operates at a 1MHz switching frequency, allowing small external components to be used. Low quiescent current during regulation maximizes the energy usage from the backup capacitor.ApplicationsBackup Capacitor SystemsPower Failure Backup SystemsSolid-State Drives

The LTC3644/LTC3644-2 is a quad 1.25A output, high efficiency synchronous monolithic step-down regulator capable of operating from input supplies up to 17V. The switching frequency is internally fixed to 1MHz or 2.25MHz with a ±50% synchronization range. The regulator features ultralow quiescent current and high efficiency over a wide VINand VOUTrange.The step-down regulator operates from an input voltage range of 2.7V to 17V and provides an adjustable output range from 0.6V to VINwhile delivering up to 1.25A of output current per channel. LTC3644/LTC3644-2 can be configured for quad 1.25A outputs, triple 2.5A/1.25A/1.25A outputs, dual 2.5A outputs, or dual 3.75A/1.25A outputs. A user selectable mode input is provided to allow the user to trade off ripple noise for light load efficiency; Burst Mode®operation provides the highest efficiency at light loads, while forced-continuous mode provides the lowest ripple noise. The regulators can be synchronized to an external clock.ApplicationsBattery Powered SystemsPoint-of-Load SuppliesPortable – Handheld Scanners and Cameras

The LTC3646 is a high efficiency, step-down DC/DC converter with internal high side and synchronous power FETs. It draws only 140μA typical DC supply current in Burst Mode operation at no load while maintaining output voltage regulation.The LTC3646 can supply up to a 1A load, and its combination of Burst Mode operation, integrated power switches and low quiescent current provides high efficiency over a broad range of load currents. Alternatively, it can be used in forced continuous mode for ripple sensitive applications.The LTC3646 has a wide 4.0V to 40V input range and its patented controlled on-time architecture and 0.6V reference voltage allow for large step-down ratios without the risk of output overvoltage. The frequency may be set between 200kHz and 3.0MHz with a program resistor or synchronized to an external clock.The internal soft-start, short-circuit protection and voltage rating make the LTC3646 a robust part ideal for high voltage applications.ApplicationsPoint of Load Power SupplyIntermediate Bus PowerAutomotive Applications

The LTC3670 is a triple power supply composed of a 400mA synchronous buck regulator and two 150mA low dropout linear regulators (LDOs). The input supply range of 2.5V to 5.5V is especially well-suited for single-cell Lithium-Ion and Lithium-Ion/Polymer applications, and for powering low voltage ASICs and SoCs from 3V, 3.3V or 5V rails. Regulated output voltages are programmed via external resistors. Each output has its own enable pin for maximum flexibility.The 400mA buck regulator features constant-frequency 2.25MHz operation, allowing small surface mount inductors and capacitors to be used. Burst Mode operation maintains high efficiency in light-load and no-load conditions. Internal control-loop compensation simplifies application design.The LTC3670 is available in a 0.75mm profile, 3mm × 2mm 12-lead DFN package.APPLICATIONSHandheld ProductsPortable InstrumentsSingle-Cell Li-Ion/Li-Polymer Powered DevicesDMB/DVB-H Multimedia Cell PhonesMultivoltage Power for Digital Logic, I/O, FPGAs, CPLDs, ASICs, SoCs, CPUs and RF Chipsets

The LTC3672B-1 is a triple power supply composed of a 400mA synchronous buck regulator and two 150mA low dropout linear regulators (LDOs), where one of the LDOs can be powered from the buck output to improve efficiency. Constant-frequency 2.25MHz operation is maintained down to very light loads. The input supply range of 2.9V to 5.5V is especially well-suited for single-cell Lithium-Ion and Lithium-Polymer applications, and for powering low voltage ASICs from 3.3V or 5V rails.The LTC3672B-1 regulates 1.8V at the buck output, 1.2V at the LDO1 output, and 2.8V at the LDO2 output. External component count is minimal—all that is needed is a single inductor, an input capacitor, and output capacitors for each of the three outputs. Control loop compensation is internal to the LTC3672B-1.The LTC3672B-1 is available in a 2mm x 2mm x 0.75mm 8-Lead DFN package.Buck VoutLDO 1LDO 2LTC3672B-11.8V1.2V2.8VLTC3672B-21.2V2.8V1.8VApplicationsDMB CellphonesHandheld Products (PDA, PMP, GPS)Multivoltage Power for Digital Logic, I/O, FPGAs, CPLDs, ASICs, CPUs, and RF Chipsets

The LTC3675/LTC3675-1 are a digitally programmable high efficiency multioutput power supplies plus dual string LED driver ICs optimized for high power single cell Li-Ion/Polymer applications. The DC/DCs consist of four synchronous buck converters (1A/1A/500mA/500mA), one synchronous boost DC/DC (1A), and one buck-boost DC/DC (1A) all powered from a 2.7V to 5.5V input. The 40V LED driver can regulate up to 25mA of current through two LED strings with up to 10 LEDs each. The LED driver may also be configured as a general purpose high voltage boost converter.DC/DC enables, output voltages, switch slew rates and operating modes may all be independently programmed over I2C or used in standalone mode via simple I/O and power-up defaults. The buck DC/DCs may be used independently or paralleled to achieve higher output currents with a shared inductor. LED enable, 60dB brightness control and up/down gradation are programmed using I2C. Alarm levels for low VINand high die temperature may also be programmed via I2C with a maskable interrupt output to monitor DC/DC and system faults.Pushbutton ON/OFF/RESET control and a power-on reset output provide flexible and reliable power-up sequencing. The LTC3675/LTC3675-1 are available in a low profile (0.75mm), thermally enhanced 44-lead 4mm × 7mm QFN package.ApplicationsHigh Power (5W to 10W) Single Cell Li-Ion/Polymer ApplicationsPortable Industrial Applications, Handy Terminals, Portable InstrumentsMultioutput Low Voltage Power Supplies

The LTC3676 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. The LTC3676-1 has a ±1.5A buck regulator configured to support DDR termination plus a VTTR reference output. An I2C serial port is used to control regulator enables, power-down sequencing, output voltage levels, dynamic voltage scaling, operating modes and status reporting.Regulator start-up is sequenced by connecting outputs to enable pins in the desired order or via the I2C port. System power-on, power-off and reset functions are controlled by pushbutton interface, pin inputs, or I2C.The LTC3676 supports i.MX, PXA and OMAP processors with eight independent rails at appropriate power levels. Other features include interface signals such as the VSTB pin that toggles between programmed run and standby output voltages on up to four rails simultaneously. The device is available in a 40-lead 6mm × 6mm QFN and 48-lead exposed pad LQFP packages.APPLICATIONSSupports Freescale i.MX6, ARM Cortex, and Other Application ProcessorsHandheld Instruments and ScannersPortable Industrial and Medical DevicesAutomotive InfotainmentHigh End Consumer DevicesMulti-Rail Systems

The LTC3677-3 is a highly integrated power management IC for single-cell Li-Ion/Polymer battery applications. It includes a PowerPath manager with automatic load prioritization, a battery charger, an ideal diode, input overvoltage protection and numerous other internal protection features. The LTC3677-3 is designed to accurately charge from current limited supplies such as USB by automatically reducing charge current such that the sum of the load current and the charge current does not exceed the programmed input current limit (100mA or 500mA modes). The LTC3677-3 reduces the battery voltage at elevated temperatures to improve safety and reliability. The three step-down switching regulators and two LDOs provide a wide range of available supplies. The LTC3677-3 also includes a pushbutton input to control power sequencing and system reset. The LTC3677-3 has pushbutton timing and sequencing designed to support the SiRF Atlas IV processor. The LTC3677-3 is available in a low profile 4mm × 7mm × 0.75mm 44-pin QFN package.ApplicationsPNDs, DMB/DVB-H, Digital/Satellite Radio, Media PlayersPortable Industrial/Medical ProductsOther USB-Based Handheld Products