LT3080 Low Dropout Regulator

By Analog Devices Inc 58

LT3080 Low Dropout Regulator

Linear Technology's LT3080 is a 1.1 A low dropout linear regulator that can be paralleled to increase output current or spread heat in surface mounted boards. Architected as a precision current source and voltage follower allows this new regulator to be used in many applications requiring high current, adjustability to zero, and no heat sink. Also the device brings out the collector of the pass transistor to allow low dropout operation - down to 300 milivolts - when used with multiple supplies.

A key feature of the LT3080 is the capability to supply a wide output voltage range. By using a reference current through a single resistor, the output voltage is programmed to any level between zero and 36 V. The LT3080 is stable with 2.2 µF of capacitance on the output, and the IC uses small ceramic capacitors that do not require additional ESR as is common with other regulators.

Internal protection circuitry includes current limiting and thermal limiting. The LT3080 regulator is offered in the 8-lead MSOP (with an exposed pad for better thermal characteristics), a 3 mm x 3 mm DFN, 5-lead TO-220 and a simple-to-use 3-lead SOT-223 version.

  • Outputs may be paralleled for higher output current or spreading PCB heat
  • Low dropout voltage: 300 mV (2 supply operation)
  • Low noise: 40 µVRMS wideband (10 kHz to 100 kHz)
  • Stable 10 µA current source reference
  • Single-resistor programs VOUT
  • Adjustable VOUT range: 0 V to 36 V
  • 1% initial accuracy of set pin current
  • Output current: 1.1 A
  • Minimum load current: 0.5 mA
  • Stable with ceramic, aluminum, or tantalum capacitors
  • Current limiting
  • Thermal limiting
  • High current all surface-mount supply
  • High efficiency linear regulator
  • Post regulator for switching supplies
  • Low parts count variable voltage supply
  • Low output voltage power supplies