LTC3829 - 3-Phase, Single Output Synchronous Step-Down DC/DC Controller with Diffamp


  • Optional Nonlinear Control for Fast Response
  • ±0.75%, 0.6V Reference Accuracy
  • PWM, Stage Shedding™ or Burst Mode® Operation
  • High Efficiency: Up to 95%
  • RSENSE or DCR Current Sensing
  • Programmable DCR Temperature Compensation
  • Phase-Lockable Fixed Frequency: 250kHz to 770kHz
  • True Remote Sense Differential Amplifier
  • Programmable Active Voltage Positioning (AVP)
  • Triple N-Channel MOSFET Synchronous Drive
  • Wide VIN Range: 4.5V to 38V Operation
  • VOUT Range: 0.6V to 5V without Diffamp
  • VOUT Range: 0.6V to 3.3V with Diffamp
  • Clock Input and Output for 6-Phase Operation
  • Adjustable Soft-Start or VOUT Tracking
  • 38-Pin (5mm × 7mm) QFN and FE Packages
  • Applications

Typical Application

LTC3829 Typical Application
LTC3829 Typical Application


The LTC3829 is a high performance 3-phase single output synchronous step-down DC/DC switching controller that drives all N‑channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phase-lockable frequency of up to 770kHz. Power loss and noise due to ESR of the input capacitors are minimized by operating the three controller output stages out of phase.

The LTC3829 can be configured for 6-phase operation, has DCR temperature compensation, and output foldback current limiting. This device features a precision 0.6V reference and a power good indicator.

Light load efficiency is optimized by using a choice of output Stage Shedding or Burst Mode operation. A differential amplifier provides true remote sensing of the output voltage at the point of load.

The LTC3829 is available in both low profile 38-pin 5mm x 7mm QFN and Exposed Pad FE packages.


For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
LTC3829EFE#PBF TSSOP-38 FE E 05-08-1772 RoHS
LTC3829EFE#TRPBF TSSOP-38 FE E 05-08-1772 RoHS
LTC3829EUHF#PBF 5x7 QFN-38 UHF E 05-08-1701 RoHS
LTC3829EUHF#TRPBF 5x7 QFN-38 UHF E 05-08-1701 RoHS
LTC3829IFE#PBF TSSOP-38 FE I 05-08-1772 RoHS
LTC3829IFE#TRPBF TSSOP-38 FE I 05-08-1772 RoHS
LTC3829IUHF#PBF 5x7 QFN-38 UHF I 05-08-1701 RoHS
LTC3829IUHF#TRPBF 5x7 QFN-38 UHF I 05-08-1701 RoHS

LTC3829 Package Drawing
LTC3829 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
LTC3829EFE#PBF TSSOP-38 E $5.80 $4.06 Yes
LTC3829EFE#TRPBF TSSOP-38 E $4.12 Yes
LTC3829EUHF#PBF 5x7 QFN-38 E $5.30 $3.71 Yes
LTC3829EUHF#TRPBF 5x7 QFN-38 E $3.77 Yes
LTC3829IFE#PBF TSSOP-38 I $6.56 $4.59 Yes
LTC3829IFE#TRPBF TSSOP-38 I $4.65 Yes
LTC3829IUHF#PBF 5x7 QFN-38 I $6.13 $4.29 Yes
LTC3829IUHF#TRPBF 5x7 QFN-38 I $4.35 Yes
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* 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 Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC1530A LTC3829EUHF Demo Board | 3-Phase Buck, 7V ≤ VIN ≤ 14V, Vout = 1.5V @ 60A $150.00
DC1675A LTC3829EUH Demo Board | LTC3829(x2) 3-Phase Buck, 7V ≤ VIN ≤ 14V, VOUT= 1.5V @ 120A $150.00
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Click here to view our complete list of demo boards


  • Applications
  • Notebook and Palmtop Computers
  • Telecom Systems
  • Portable Instruments
  • DC Power Distribution Systems

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Design Tools


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LTC3829 Parallel


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