LTC3427 - 500mA, 1.25MHz Synchronous Step-Up DC/DC Converter in 2mm x 2mm DFN Package


  • High Efficiency: Up to 94%
  • 3.3V at 200mA from Two Alkaline Cells
  • 5V at 200mA from a Single Li-Ion Cell
  • Inrush Current Limiting and Soft-Start
  • Output Disconnect in Shutdown
  • 1.8V to 5V VIN Range
  • 1.8V to 5.25V VOUT Range
  • 1.25MHz Fixed Frequency, Low Noise PWM
  • Internal Synchronous Rectifier
  • Logic Controlled Shutdown (<1μA)
  • Anti-Ringing Control Minimizes EMI
  • Tiny External Components
  • Short-Circuit Protection
  • Low Profile (0.75mm × 2mm × 2mm) DFN Package

Typical Application

LTC3427 Typical Application
LTC3427 Typical Application


The LTC3427 is the industry’s first high efficiency, fixed frequency, step-up DC/DC converter with true output disconnect in a 6-lead 2mm × 2mm DFN package. Requiring minimal external components, the LTC3427 operates from an input voltage as low as 1.8V. The LTC3427 contains an internal 0.525Ω N-channel MOSFET switch and a 0.575Ω P-channel MOSFET synchronous rectifier, which enables it to supply 200mA at 3.3V from a 2-cell alkaline battery input.

The LTC3427 limits inrush current during start-up and provides a soft-start of VOUT. A switching frequency of 1.25MHz minimizes solution footprint by allowing the use of tiny, low profile inductors and ceramic capacitors and produces very low VOUT ripple. The current mode PWM design is internally compensated, reducing external parts count. Anti-ringing control reduces EMI in discontinuous mode operation. The LTC3427 also features low shutdown current of under 1μA and thermal shutdown.


CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

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

Part Number Package Code Temp Package
LTC3427EDC#PBF 2x2 DFN-6 DC6 E 05-08-1703 Yes
LTC3427EDC#TRMPBF 2x2 DFN-6 DC6 E 05-08-1703 Yes
LTC3427EDC#TRPBF 2x2 DFN-6 DC6 E 05-08-1703 Yes

LTC3427 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
LTC3427EDC#PBF 2x2 DFN-6 E $2.59 Yes
LTC3427EDC#TRMPBF 2x2 DFN-6 E $2.59 $1.83 Yes
LTC3427EDC#TRPBF 2x2 DFN-6 E $2.59 $1.81 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
DC856A LTC3427EDC Demo Board | 1.8V ≤ VIN ≤ 3.6V, Vout = 3.3V @ 180mA Contact Factory
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Click here to view our complete list of demo boards


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