LTC3609 Monolithic Synchronous Step-Down DC/DC Converter

32V, 6A Monolithic Synchronous Step-Down DC/DC Converter

Image of Linear Technology's LTC3609The LTC3609 is a high efficiency, monolithic synchronous step-down DC/DC converter that can deliver up to 6A output current from a 4V to 32V (36V maximum) input supply. It uses a valley current control architecture to deliver very low duty cycle operation at high frequency with excellent transient response. The operating frequency is selected by an external resistor and is compensated for variations in VIN and VOUT.

The LTC3609 can be configured for discontinuous or forced continuous operation at light load. Forced continuous operation reduces noise and RF interference while discontinuous mode provides high efficiency by reducing switching losses at light loads.

Fault protection is provided by internal foldback current limiting, an output overvoltage comparator and an optional short-circuit shutdown timer. Soft-start capability for supply sequencing is accomplished using an external timing capacitor. The regulator current limit is user programmable. A power good output voltage monitor indicates when the output is in regulation. The LTC3609 is available in a compact 7mm × 8mm QFN package. DiagramDatasheet


  • 6A Output Current
  • Wide VIN Range = 4V to 32V (36V Maximum)
  • Internal N-Channel MOSFETs
  • True Current Mode Control
  • Optimized for High Step-Down Ratios
  • tON(MIN) ≤ 100ns
  • Extremely Fast Transient Response
  • Stable with Ceramic COUT
  • ±1% 0.6V Voltage Reference
  • Power Good Output Voltage Monitor
  • Adjustable On-Time/Switching Frequency
  • Adjustable Current Limit
  • Programmable Soft-Start
  • Output Overvoltage Protection
  • Optional Short-Circuit Shutdown Timer
  • Low Shutdown IQ: 15µA
  • Available in a 7mm × 8mm 52-Pin QFN Package


ImageManufacturer Part NumberDescriptionFunctionOutput ConfigurationAvailable Quantity
IC REG BUCK ADJ 6A 52QFNLTC3609EWKG#PBFIC REG BUCK ADJ 6A 52QFNStep-DownPositive1385 - Immediate
LTC3609EWKG#PBF product page link
Published: 2013-10-11