Analog Devices

The LT1585-1.5/LT1585A-1.5 are low dropout, 3-terminal regulators with 4.6A and 5A output current capability respectively, and a fixed 1.5V output voltage. The designs are optimized for low voltage applications where transient response and minimum input voltage are critical. Similar to the LT1084, they have lower dropout and faster transient response. These improvements make them ideal for low voltage microprocessor applications, especially as the regulator in an Intel processor GTL+ supply.Current limit is trimmed to ensure specified output current and controlled short-circuit current. On-chip thermal limiting provides protection against any combination of overload that creates excessive junction temperatures.The LT1585-1.5/LT1585A-1.5 are available in the through-hole 3-pin TO-220 power package and 3-pin plastic DD.Output CurrentOutput Voltage OptionsLT1584, -3.3, -3.38, -3.45, -3.67AAdj, 3.3V, 3.38V, 3.45V, 3.6VLT1585, -3.3, -3.38, -3.45, -3.64.6AAdj, 3.3V, 3.38V, 3.45V, 3.6VLT1585A, LT1585A-3.35AAdj, 3.3VLT1585-1.5, LT1585A-1.54.6A/5AFixed 1.5VLT1587, -3.3, -3.45, -3.63AAdj. 3.3V, 3.45V, 3.6VLT1587-1.53AFixed 1.5VApplicationsGTL+ Power SupplyLow Voltage Logic SuppliesBattery-Powered Circuitry

The LT®1584/LT1585/LT1587 are low dropout three-terminal regulators with 7A, 4.6A and 3A output current capability, respectively. Design has been optimized for low voltage applications where transient response and minimum input voltage are critical. Similar to the LT1083/4/5 family, it has lower dropout voltage and faster transient response. These improvements make it ideal for low voltage microprocessor applications requiring a regulated 2.5V to 3.6V output with an input supply below 7V.Current limit is trimmed to ensure specified output current and controlled short-circuit current. On-chip thermal limiting provides protection against any combination of overload that would create excessive junction temperatures.The LT1585/LT1587 are available in both the through-hole and surface mount versions of the industry standard 3-pin TO-220 power package. The LT1584 is available in the through-hole 3-pin TO-220 power package.Output CurrentOutput Voltage OptionsLT1584, -3.3, -3.38, -3.45, -3.67AAdj, 3.3V, 3.38V, 3.45V, 3.6VLT1585, -3.3, -3.38, -3.45, -3.64.6AAdj, 3.3V, 3.38V, 3.45V, 3.6VLT1585A, LT1585A-3.35AAdj, 3.3VLT1585-1.5, LT1585A-1.54.6A / 5AFixed 1.5VLT1587, -3.3, -3.45, -3.63AAdj, 3.3V, 3.45V, 3.6VLT1587-1.53AFixed 1.5VApplicationsPentium™Processor SuppliesPowerPC™SuppliesOther 2.5V to 3.6V Microprocessor SuppliesLow Voltage Logic SuppliesBattery-Powered CircuitryPost Regulator for Switching Supply

The LT1584/LT1585/LT1587 are low dropout three-terminal regulators with 7A, 4.6A and 3A output current capability, respectively. Design has been optimized for low voltage applications where transient response and minimum input voltage are critical. Similar to the LT1083/4/5 family, it has lower dropout voltage and faster transient response. These improvements make it ideal for low voltage microprocessor applications requiring a regulated 2.5V to 3.6V output with an input supply below 7V.Current limit is trimmed to ensure specified output current and controlled short-circuit current. On-chip thermal limiting provides protection against any combination of overload that would create excessive junction temperatures.The LT1585/LT1587 are available in both the through-hole and surface mount versions of the industry standard 3-pin TO-220 power package. The LT1584 is available in the through-hole 3-pin TO-220 power package.Output CurrentOutput Voltage OptionsLT1584, -3.3, -3.38, -3.45, -3.67AAdj, 3.3V, 3.38V, 3.45V, 3.6VLT1585, -3.3, -3.38, -3.45, -3.64.6AAdj, 3.3V, 3.38V, 3.45V, 3.6VLT1585A, LT1585A-3.35AAdj, 3.3VLT1585-1.5, LT1585A-1.54.6A / 5AFixed 1.5VLT1587, -3.3, -3.45, -3.63AAdj, 3.3V, 3.45V, 3.6VLT1587-1.53AFixed 1.5VApplicationsPentium™Processor SuppliesPowerPC™SuppliesOther 2.5V to 3.6V Microprocessor SuppliesLow Voltage Logic SuppliesBattery-Powered CircuitryPost Regulator for Switching Supply

The LT1610 is a micropower fixed frequency DC/DC converter that operates from an input voltage as low as 1V. Intended for small, low power applications, it switches at 1.7MHz, allowing the use of tiny capacitors and inductors.The device can generate 3V at 30mA from a single cell (1V) supply. An internal compensation network can be connected to the LT1610’s VCpin, eliminating two external components. No-load quiescent current of the LT1610 is 30µA, and the internal NPN power switch handles a 300mA current with a voltage drop of 300mV.The LT1610 is available in 8-lead MSOP and SO packages.ApplicationsPagersCordless PhonesBattery BackupLCD BiasPortable Electronic Equipment

The LT1612 is an 800kHz, synchronous step-down DC/DC converter that operates from an input voltage as low as 2V. Internal 0.45Ohms switches deliver output currents up to 500mA, and the 800kHz switching frequency allows the use of small, low value ceramic input and output capacitors. Input voltage ranges from 5.5V down to 2V and output voltage can be set as low as the 620mV reference. The device features Burst Mode operation, keeping efficiency high at light loads. Burst Mode operation can be defeated by pulling the MODE pin high, enabling constant switching throughout the load range for low noise.No-load quiescent current is 160µA and shutdown current is less than 1µA. The device is available in 8-lead SO and MSOP packages.ApplicationsPortable DevicesLithium-Ion Step-Down Converters5V to 3.3V Conversion2-Cell Alkaline Step-Down Converters

The LT1613 is the industry’s first 5-lead SOT-23 current mode DC/DC converter. Intended for small, low power applications, it operates from an input voltage as low as 1.1V and switches at 1.4MHz, allowing the use of tiny, low cost capacitors and inductors 2mm or less in height. Its small size and high switching frequency enables the complete DC/DC converter function to take up less than 0.2 square inches of PC board area. Multiple output power supplies can now use a separate regulator for each output voltage, replacing cumbersome quasi-regulated approaches using a single regulator and a custom transformer.A constant frequency, internally compensated current mode PWM architecture results in low, predictable output noise that is easy to filter. The high voltage switch on the LT1613 is rated at 36V, making the device ideal for boost converters up to 34V as well as for Single-Ended Primary Inductance Converter (SEPIC) and flyback designs. The device can generate 5V at up to 200mA from a 3.3V supply or 5V at 175mA from four alkaline cells in a SEPIC design.The LT1613 is available in the 5-lead SOT-23 package.ApplicationsDigital CamerasPagersCordless PhonesBattery BackupLCD BiasMedical Diagnostic EquipmentLocal 5V or 12V SupplyExternal ModemsPC Cards

The LT1614 is a fixed frequency, inverting mode switching regulator that operates from an input voltage as low as 1V. Utilizing a low noise topology, the LT1614 can generate a negative output down to −24V from a 1V to 5V input. Fixed frequency switching ensures a clean output free from low frequency noise. The device contains a low-battery detector with a 200mV reference and shuts down to less than 10µA. No load quiescent current of the LT1614 is 1mA and the internal NPN power switch handles a 500mA current with a voltage drop of just 295mV.High frequency switching enables the use of small inductors and capacitors. Ceramic capacitors can be used in many applications, eliminating the need for bulky tantalum types.The LT1614 is available in 8-lead MSOP or SO packages.ApplicationsMR Head BiasLCD BiasGaAs FET BiasPositive-to-Negative Conversion

The LT1615/LT1615-1 are micropower step-up DC/DC converters in a 5-lead low profile (1mm) ThinSOT package. The LT1615 is designed for higher power systems with a 350mA current limit and an input voltage range of 1.2V to 15V, whereas the LT1615-1 is intended for lower power and single-cell applications with a 100mA current limit and an extended input voltage range of 1V to 15V. Otherwise, the two devices are functionally equivalent. Both devices feature a quiescent current of only 20µA at no load, which further reduces to 0.5µA in shutdown. A current limited, fixed off-time control scheme conserves operating current, resulting in high efficiency over a broad range of load current. The 36V switch allows high voltage outputs up to 34V to be easily generated in a simple boost topology without the use of costly transformers. The LT1615’s low off-time of 400ns permits the use of tiny, low profile inductors and capacitors to minimize footprint and cost in space-conscious portable applications.ApplicationsLCD BiasHandheld ComputersBattery BackupDigital Cameras

The LT1616 is a current mode PWM step-down DC/DC converter with internal 0.6A power switch, packaged in a tiny 6-lead SOT-23. The wide input range of 3.6V to 25V makes the LT1616 suitable for regulating a wide variety of power sources, from 4-cell batteries and 5V logic rails to unregulated wall transformers and lead-acid batteries. Its high operating frequency allows the use of tiny, low cost inductors and ceramic capacitors. With its internal compensation eliminating additional components, a complete 400mA step-down regulator fits onto 0.15 square inches of PC board area.The constant frequency current mode PWM architecture and stable operation with ceramic capacitors results in low, predictable output ripple. Current limiting provides protection against shorted outputs. The low current (<1µA) shutdown provides complete output disconnect, enabling easy power management in battery-powered systems.ApplicationsWall Transformer RegulationLocal Logic Supply Conversion:12V to 5V12V or 5V to 3.3V, 2.5V or 1.8VBattery-Powered EquipmentDistributed Supply RegulationDigital Cameras

The LT1617/LT1617-1 are micropower inverting DC/DC converters in a 5-lead SOT-23 package. The LT1617 is designed for higher power systems with a 350mA current limit and an input voltage range of 1.2V to 15V, whereas the LT1617-1 is intended for lower power and single-cell applications with a 100mA current limit and an extended input voltage range of 1V to 15V. Otherwise, the two devices are functionally equivalent. Both devices feature a quiescent current of only 20µA at no load, which further reduces to 0.5µA in shutdown. A current limited, fixed off-time control scheme conserves operating current, resulting in high efficiency over a broad range of load current. The 36V switch allows high voltage outputs up to –34V to be easily generated without the use of costly transformers. The LT1617’s low off-time of 400ns permits the use of tiny, low profile inductors and capacitors to minimize footprint and cost in space-conscious portable applications.ApplicationsLCD BiasHandheld ComputersBattery BackupDigital Cameras