76V, 1A step-down converter has 12 µA Iq, suits automotive applications

March 26, 2014 // By Graham Prophet
LTC3637 is a 76V input-capable high efficiency buck converter that delivers up to 1A of continuous output current. It operates from an input voltage range of 4V to 76V, making it suitable for telecom, industrial, avionic and automotive applications.

The device uses a programmable peak current-mode design to optimise efficiency over a broad range of output currents. It delivers efficiencies as high as 90% and requires only 12 µA of quiescent current. A user-programmable output current limit can set output current from 100 mA to 1A. The LTC3637 can be programmed with fixed output voltages of 1.8V, 3.3V or 5V or a resistor divider can be used to program outputs from V IN to 0.8V. Its thermally enhanced MSOP or 3 x 5mm DFN packages offer additional pin spacing required for high voltage inputs. The combination of its MSOP or DFN package and only four tiny externals provide a compact solution footprint for a wide array of applications.

The LTC3637 has an internal 350-mΩ power MOSFET that draws only 12 µA at no load while maintaining output voltage regulation, suiting it tor always-on battery-powered applications. Due to the inherent stability of the converter, no external compensation is required, thereby simplifying design and minimising the solution footprint. Additional features include a precise 0.8V ±1% feedback voltage reference and internal or external soft-start.

In various package options and temperature ranges, pricing ranges from $3.20 to $3.77 (1000), with a hi-rel version at $9.50 (1000).

Linear Technology; www.linear.com/product/LTC3637