LTC3786 - Low IQ Synchronous Boost Controller

Features

  • Synchronous Operation For Highest Efficiency and Reduced Heat Dissipation
  • Wide VIN Range: 4.5V to 38V (40V Abs Max) and Operates Down to 2.5V After Start-Up
  • Output Voltages Up to 60V
  • ±1% 1.2V Reference Voltage
  • RSENSE or Inductor DCR Current Sensing
  • 100% Duty Cycle Capability for Synchronous MOSFET
  • Low Quiescent Current: 55μA
  • Phase-Lockable Frequency (75kHz to 850kHz)
  • Programmable Fixed Frequency (50kHz to 900kHz)
  • Adjustable Output Voltage Soft-Start
  • Power Good Output Voltage Monitor
  • Low Shutdown Current IQ: <8μA
  • Internal 5.4V LDO for Gate Drive Supply
  • Thermally Enhanced 16-Pin 3mm × 3mm QFN and MSOP Packages
Designed for Automotive and Transportation Applications
AEC-Q100 data available for specific packages


Typical Application

LTC3786 Typical Application
LTC3786 Typical Application

Description

The LTC®3786 is a high performance synchronous boost converter controller that drives all N-channel power MOSFETs. Synchronous rectification increases efficiency, reduces power losses and eases thermal requirements, allowing the LTC3786 to be used in high power boost applications.

A 4.5V to 38V input supply range encompasses a wide range of system architectures and battery chemistries. When biased from the output of the boost converter or another auxiliary supply, the LTC3786 can operate from an input supply as low as 2.5V after start-up. The 55μA no-load quiescent current extends operating run time in battery-powered systems.

The operating frequency can be set for a 50kHz to 900kHz range or synchronized to an external clock using the internal PLL. The LTC3786 also features a precision 1.2V reference and a power good output indicator. The SS pin ramps the output voltage during start-up. The PLLIN/MODE pin selects among Burst Mode® operation, pulse-skipping mode or continuous inductor current mode at light loads.

Packaging

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
Drawing
RoHS
LTC3786EMSE#PBF MS-16E MSE E 05-08-1667 Yes
LTC3786EMSE#TRPBF MS-16E MSE E 05-08-1667 Yes
LTC3786EUD#PBF 3x3 QFN-16 UD E 05-08-1691 Yes
LTC3786EUD#TRPBF 3x3 QFN-16 UD E 05-08-1691 Yes
LTC3786IMSE#PBF MS-16E MSE I 05-08-1667 Yes
LTC3786IMSE#TRPBF MS-16E MSE I 05-08-1667 Yes
LTC3786IUD#PBF 3x3 QFN-16 UD I 05-08-1691 Yes
LTC3786IUD#TRPBF 3x3 QFN-16 UD I 05-08-1691 Yes


LTC3786 Package Drawing
LTC3786 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
(1-99)
Price
(1k)*
RoHS
LTC3786EMSE#PBF MS-16E E $3.62 $2.53 Yes
LTC3786EMSE#TRPBF MS-16E E $2.59 Yes
LTC3786EUD#PBF 3x3 QFN-16 E $3.62 $2.53 Yes
LTC3786EUD#TRPBF 3x3 QFN-16 E $2.59 Yes
LTC3786IMSE#PBF MS-16E I $4.37 $3.06 Yes
LTC3786IMSE#TRPBF MS-16E I $3.12 Yes
LTC3786IUD#PBF 3x3 QFN-16 I $4.37 $3.06 Yes
LTC3786IUD#TRPBF 3x3 QFN-16 I $3.12 Yes
Buy NowRequest Samples
* 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
DC1641A LTC3786 MS16E Demo Board 5V VIN 24V; VOUT = 24V @ Up to 10A $125.00
Buy Now
Click here to view our complete list of demo boards

Designed for Automotive and Transportation Applications

AEC-Q100 data is available for these specific part numbers. Please contact your local sales representative for more information regarding reliability reports or to inquire about parts that are not included. For more information, view our Automotive and Transportation page

Part Number Package Temp Price
(1-99)
Price
(1k)*
RoHS
LTC3786IMSE#PBF MS-16E I $4.37 $3.06 Yes
LTC3786IMSE#TRPBF MS-16E I $3.12 Yes
LTC3786IUD#PBF 3x3 QFN-16 I $4.37 $3.06 Yes
LTC3786IUD#TRPBF 3x3 QFN-16 I $3.12 Yes
Buy NowRequest Samples
* 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.

Applications

  • Industrial and Automotive Power Supplies
  • Automotive Start-Stop Systems
  • Medical Devices
  • High Voltage Battery-Powered Systems

Product Notifications

Please login to your MyLinear account for notifications of datasheet updates, new document releases and LTspice model announcements for your favorite products. If you do not have a MyLinear account you may Sign Up Now.

Forgot your password? Click here.
Need help? Email mylinear@linear.com with questions and comments.

Design Tools

LTspice

LTspice® software is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. Click here to download LTspice

To launch a ready to run LTspice demonstration circuit for this part:

To explore other ready to run LTspice demonstration circuits, please visit our Demo Circuits Collection.

Models for the following parts are available in LTspice:
LTC3786

LTpowerCAD

The LTpowerCAD design tool is a complete power supply design tool program that can significantly ease the tasks of power supply design. It guides users to a solution, selects power stage components, provides detailed power efficiency, shows quick loop bode plot stability and load transient analysis, and can export a final design to LTspice for simulation. Click here to download LTpowerCAD

To open the project file for this circuit:

  • Step 1: If you have not installed LTpowerCAD on this computer, download and install LTpowerCAD
  • Step 2: Once LTpowerCAD is installed, click on the link(s) below to open the project file
  • Step 3: If LTpowerCAD does not automatically open after clicking the link above, you can open the project file by right clicking on the link and selecting "Save Target As." After saving the file to your computer, start LTpowerCAD and open the project file by selecting 'Open Project' from the 'File' menu

Design tools for the following parts are available in LTpowerCAD:
LTC3786
LTC3786 Parallel

Technical Support