Linear Technology LTC3786 step-up DC/DC controller

Click2Contact

Linear Technology has announced the LTC3786, a synchronous step-up DC/DC controller that replaces the boost diode with a high-efficiency N-channel MOSFET.

This 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 device can keep the synchronous MOSFET on continuously so that the output voltage follows the input voltage with minimal power loss.

The low 55 µA quiescent current extends the run time in battery-powered applications when in standby mode. This controller can produce a 24 V at 5 A output from a 12 V input with up to 98% efficiency, making it suitable for motor vehicle, industrial and medical applications.

The controller operates from an input voltage from 4.5 to 38 V during start-up, maintaining operation down to 2.5 V after start-up, and can regulate an output voltage of 60 V. The 1.2 Ω onboard N-channel MOSFET gate drivers can slew large MOSFET gates quickly, minimising transition losses and allowing for up to a 10 A output current.

It has adjustable cycle-by-cycle current limit protection and uses either a sense resistor or monitors the voltage drop across the inductor for current sensing. It has a phase-lockable switching frequency range of 75 to 850 kHz and a fixed frequency operating range from 50 to 900 kHz. It has adjustable soft-start and maintains ±1% reference voltage accuracy over an operating temperature range of -40 to 125°C.