PolyPhase Synchronous Boost Controller
Features and Benefits
- 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
The LTC3786 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.
- Industrial and Automotive Power Supplies
- Automotive Start-Stop Systems
- Medical Devices
- High Voltage Battery-Powered Systems
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Demonstration circuit DC1641 is DC/DC boost converter featuring the LTC3786 constant frequency current mode boost controller. The DC1641A operates over 5V to 24V input and provides over 5A at 6V input voltage and over 9A of output current at 10V input as shown in figure 3. The 350kHz constant frequency operation results in small and efficient circuit. The converter provides high output voltage accuracy (typically ±3%) over wide load range with no minimum load requirement. The demonstration circuit can be easily modified to generate different output voltages.
Tools & Simulations
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.
Models for the following parts are available in LTspice:
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.
To open the project file for this circuit:
Step 1: Download and install LTpowerCAD on your computer.
Step 2: Click on the link(s) in the section below to download part-specific project files.
Step 3: If the project file doesn't run, right-click the link and select "Save Target As." Then start the LTpowerCAD tool and open the project file by selecing "Open Project" from the "File" menu.
LTpowerCAD Project Files
Design tools for the following parts are available in LTpowerCAD:
LTC3786 Companion Parts
Recommended Related Parts
Technical Articles (1)
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
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 Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.