Date: 26/10/2010

Synchronous boost controller from Linear with up to 98% efficiency

Linear Technology Corporation has unveiled the LTC3786, a synchronous step-up DC/DC controller. This boost controller replaces the boost diode with a high efficiency N-channel MOSFET and eliminates the heat sink normally required in medium to high power boost converters.

In applications where the input voltage may exceed the regulated output voltage, the LTC3786 can keep the synchronous MOSFET on continuously so that the output voltage follows the input voltage with minimal power loss. The LTC3786 has a 55µA quiescent current and is reported to produce 24V at 5A output from a 12V input with up to 98% efficiency. This controller is suggested for automotive, industrial, and medical applications.

The LTC3786 operates from an input voltage ranging from 4.5V to 38V during start-up, maintaining operation down to 2.5V after start-up and can regulate an output voltage to 60V. The1.2 Ohm onboard N-channel MOSFET gate drivers are capable of slewing large MOSFET gates and therefore minimizing transition losses and allowing for up to a 10A output current.

The LTC3786 has adjustable cycle-by-cycle current limit protection and uses either a sense resistor or monitors the voltage drop across the inductor (DCR) for current sensing. The LTC3786 has a phase-lockable switching frequency range of 75kHz to 850kHz and a fixed frequency operating range from 50kHz to 900kHz. The controller also has an adjustable soft-start and maintains ±1% reference voltage accuracy.

Operating temperature range: -40°C to 125°C.

Package: Thermally enhanced MSOP-16 and a 3mm x 3mm QFN.

Price: Each US$2.80 for 1K pieces

Availablity: Now