LTC3785 - 10V, High Efficiency, Synchronous, No RSENSE Buck-Boost Controller

The LTC3785 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 is well suited for a wide variety of single or dual cell Li-Ion or multicell 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.

Protection features include foldback current limit, shortcircuit and overvoltage protection.

Features
  • Single Inductor Architecture Allows VIN Above, Below or Equal to VOUT
  • 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

Applications
  • Palmtop Computers
  • Handheld Instruments
  • Wireless Modems
  • Cellular Telephones
Packaging
Order Information
Part NumberPackageTempPrice(1-99)Price (1k)*
LTC3785EUF#PBF4x4 QFN-24E$5.09$3.56
LTC3785EUF#TRPBF4x4 QFN-24E$3.62
LTC3785IUF#PBF4x4 QFN-24I$5.54$3.88
LTC3785IUF#TRPBF4x4 QFN-24I$3.94
Demo Boards
Part NumberDescriptionPrice
DC957ALTC3785EUF Demo Board | No Rsense, 2.7V ≤ VIN ≤ 10V, Vout = 3.3V @ 3A$150.00
Datasheet
Design Note
Reliability Data
LT Journal
Press Release
LTspice
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