Analog Devices Inc./Maxim Integrated

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 LT1587-1.5 is a low dropout 3-terminal regulator with a fixed 1.5V output voltage and 3A output current capability. The design is optimized for low voltage applications where transient response and minimum input voltage are critical. Similar to the LT1085, it has lower dropout and faster transient response. These improvements make it ideal for low voltage microprocessor applications, especially as the regulator in an Intel Pentium Pro 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 LT1587-1.5 is available in both the through-hole and surface mount versions of the industry standard 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 1.5VApplicationsIntel Pentium®Pro Processor GTL+ SupplyLow Voltage Logic SuppliesBattery-Powered Circuitry

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 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 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