LTC3785-1 - 10V, High Efficiency, Buck-Boost Controller with Power Good


  • Single Inductor Architecture Allows VIN Above, Below or Equal to VOUT
  • Power Good Output Indicator
  • 2.7V to 10V Input and Output Range
  • Up to 96% Efficiency
  • Up to 10A of Output Current
  • All N-Channel MOSFETs, No RSENSE
  • True Output Disconnect During Shutdown
  • Programmable Current Limit and Soft-Start
  • Optional Short-Circuit Shutdown Timer
  • Output Overvoltage and Undervoltage Protection
  • Programmable Frequency: 100kHz to 1MHz
  • Selectable Burst Mode® Operation
  • Available in 24-Lead (4mm × 4mm) Exposed Pad QFN Package

Typical Application

LTC3785-1 Typical Application
LTC3785-1 Typical Application


The LTC3785-1 is a high power synchronous buck-boost controller that drives all N-channel power MOSFETs from input voltages above, below and equal to the output voltage. With an input range of 2.7V to 10V, the LTC3785-1 is well suited for a wide variety of single or dual cell Li-Ion or multi-cell alkaline/NiMH applications.

The operating frequency can be programmed from 100kHz to 1MHz. The soft-start time and current limit are also programmable. The soft-start capacitor doubles as the fault timer which can program the IC to latch off or recycle after a determined off time. Burst Mode operation is user controlled and can be enabled by driving the MODE pin high. The LTC3785-1 includes a Power Good output that indicates when the output voltage is within 7.5% of its designed setpoint.

Protection features include foldback current limit, short-circuit and overvoltage protection.

  Power Good
LTC3785 No
LTC3785-1 Yes


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
LTC3785EUF-1#PBF 4x4 QFN-24 UF E 05-08-1697 Yes
LTC3785EUF-1#TRPBF 4x4 QFN-24 UF E 05-08-1697 Yes

LTC3785-1 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
LTC3785EUF-1#PBF 4x4 QFN-24 E $5.36 $3.75 Yes
LTC3785EUF-1#TRPBF 4x4 QFN-24 E $3.81 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.

Click here to view our complete list of demo boards


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Design Tools


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