Features and Benefits

  • Reduces Required Input Capacitance and Power Supply Induced Noise
  • True Remote Sensing Differential Amplifier
  • 0.6V, ±1% Voltage Reference Accuracy
  • PolyPhase Controller Operates from Two to Twelve Phases
  • Current Mode Control Ensures Current Sharing
  • Phase-Lockable Fixed Frequency: 250kHz to 550kHz
  • OPTI-LOOP® Compensation Reduces COUT
  • Power Good Output Voltage Monitor
  • Wide VIN Range: 4V to 30V Operation
  • Very Low Dropout Operation: 99% Duty Cycle
  • Adjustable Soft-Start Current Ramping
  • Internal Current Foldback Plus Shutdown Timer
  • Overvoltage Soft-Latch Eliminates Nuisance Trips
  • Micropower Shutdown
  • 32-Lead 5mm x 5mm Plastic QFN Package

Product Details

The LTC3729L-6 is a PolyPhase synchronous stepdown current mode switching regulator controller with a 0.6V reference that drives N-channel external power MOSFET stages in a phase-lockable fixed frequency architecture. The PolyPhase controller drives its two output stages out of phase at frequencies up to 550kHz to minimize the RMS ripple currents in both input and output capacitors. The output clock signal allows expansion for up to 12 evenly phased controllers for systems requiring 15A to 200A of output current. This PolyPhase technique effectively multiplies the fundamental frequency by the number of channels used, improving transient response while operating each channel at an optimum frequency for efficiency. Thermal design is also simplified.

An internal differential amplifier provides true remote sensing of the regulated supply’s positive and negative output terminals as required for high current applications.

A RUN/SS pin provides both soft-start and optional timed, short-circuit shutdown. Current foldback limits MOSFET dissipation during short-circuit conditions when the overcurrent latchoff is disabled. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3729L-6 includes a power good output pin that indicates when the output voltage is inside the ±10% tolerance window.

Vin Max Vref
LTC3729 36V 0.8
LTC3729L-6 30V 0.6


  • Desktop Computers
  • Internet Servers
  • Large Memory Arrays
  • DC Power Distribution Systems

Product Lifecycle icon-recommended Production

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.

Tools & Simulations


LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.


Models for the following parts are available in LTspice:


Product Recommendations

LTC3729L-6 Companion Parts

Recommended Related Parts

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.

Support & Discussions

LTC3729L-6 Discussions

RE: ADAR1000 Beam Switching Start Address
1 day(s) ago in RF and Microwave
RE: DATA_CLK is the output clk of RX FIR(RX_SAMPLE_CLK) ?
3 day(s) ago in Design Support AD9361/AD9363/AD9364
RE: AD9361 Filter Wizard 1Rx and 1Tx setup
4 day(s) ago in Design Support AD9361/AD9363/AD9364

Sample & Buy

Sample & Buy functionality exists in desktop site
Check Inventory

The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.

Price Table Help