High power step up dc/dc controller
1 min read
Linear Technology has unveiled a high power two phase single output synchronous step up dc/dc controller, in which the boost diodes are replaced with high efficiency n-channel mosfets. This is said to eliminate the heat sink normally required in medium to high power boost converters.
The LTC3787 can produce a 24V at 10A output from a 12V input at up to 97% efficiency. Its 135µA standby quiescent current makes it suitable for high power automotive audio amplifiers, as well as for industrial and medical applications where a step-up dc/dc converter must deliver high power in a small solution size.
Operating from an input ranging from 4.5 to 38V during start-up, the part maintains operation down to 2.5V after start up and can regulate an output voltage as high as 60V. The 1.2? onboard n-channel mosfet gate drivers can slew large mosfet gates quickly. The device's current mode architecture, clock output and phase modulation enables easy paralleling of multiple devices for up to 12 phase operation.
The LTC3787 has a phase lockable frequency from 75kHz to 850kHz or a selectable fixed frequency from 50kHz to 900kHz. In applications where the input voltage exceeds the regulated output voltage, the LTC3787 keeps the synchronous mosfet on continuously so that the output voltage follows the input voltage with minimal power loss.
