Analog Devices Inc. LTC3638 & LTC3639 Step-Down Regulators

Analog Devices Inc. LTC3638 and LTC3639 High-Efficiency Step-Down Regulators maintain a regulated output voltage at no load with an internal power switch at only 12μA typical DC supply current. The LTC3638 and LTC3639 incorporate low quiescent current, integrated power switch, Burst Mode® operation, and programmable peak current limit creating high efficiency over a broad range of load currents. A programmable peak current limit creates a simple method for optimizing efficiency and for reducing output ripple and component size. 

The Analog Devices LTC3638 and LTC3639 regulate from a wide variety of power sources with its wide input range and programmable overvoltage lockout. The power system start-up is well-controlled in any environment guaranteed through a precise run threshold and soft-start feature. The step-down regulators are high-voltage capable, thermally enhanced 16-lead MSE package with four missing pins.


  • Wide operating input voltage range
  • No compensation required
  • Adjustable maximum output current
  • 100% duty cycle low dropout operation
  • 12μA low quiescent current 
  • 0.8V to VIN wide output range
  • 0.8V ±1% feedback voltage reference
  • Precise RUN pin threshold
  • Internal or external soft-start
  • Programmable 1.8V, 3.3V, 5V, or adjustable output
  • Few external components required
  • Programmable input overvoltage lockout
  • Thermally enhanced high voltage MSOP package


  • Industrial control supplies
  • Medical devices
  • Distributed power systems
  • Portable instruments
  • Battery-operated devices
  • Avionics
  • Automotive

Typical Application Circuits

Publicado: 2017-05-11 | Actualizado: 2022-03-29