Features

• Synchronous Operation For Highest Efficiency and Reduced Heat Dissipation
• Wide V_IN 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
• R_SENSE 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 I_Q: <8μA
• Internal 5.4V LDO for Gate Drive Supply
• Thermally Enhanced 16-Pin 3mm × 3mm QFN and MSOP Packages

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.