Analog Devices Inc. LTC3126 Synchronous Buck Converters

Analog Devices Inc. LTC3126 Synchronous Buck Converters are high efficiency with internal no loss PowerPath™. This supports the converters having uninterrupted operation from two separate input power sources. The internal PowerPath™ has fast, automatic switchover that eliminates the need for hold-up capacitors and decreases disturbances on the output rail. Complete feedback of the power system status is provided by independent input and output power good signals, and an active input channel indicator.

Analog Devices Inc. LTC3126 has a wide input voltage range of 2.4V to 42V and 2.5A output current capability. The converters use a wide variety of power sources including supercapacitors, automotive batteries, unregulated wall adapters, and single to multi-cell stacks of most battery chemistries.


  • Seamless, automatic transition between two input power sources
  • 2.4V to 42V input voltage range
  • 0.818V to VIN output voltage range
  • Up to 2.5A continuous output current
  • Pin selectable priority and ideal diode-OR modes
  • Burst Mode operation, IQ = 2μA
  • 95% efficiency at 1A, VIN = 12V, VOUT = 5V
  • 1μA current in shutdown
  • Programmable input UVLO thresholds
  • Input valid, priority channel, and PGOOD indicators
  • 200kHz to 2.2MHz fixed frequency PWM
  • Synchronizable to an external clock
  • Current mode control with 60ns minimum on-time
  • Minimal external components
  • Thermally enhanced 28-lead 4mm x 5mm QFN and 28-lead TSSOP packages


  • Portable industrial/communications test equipment
  • Battery and supercapacitor backup power
  • Automotive power with battery backup
  • Uninterruptible power supplies

Typical Application Circuit

Application Circuit Diagram - Analog Devices Inc. LTC3126 Synchronous Buck Converters
Published: 2017-04-25 | Updated: 2022-03-11