Buck regulator has integrated MOSFET

Texas Instruments Inc. (TI) has expanded its high-voltage point-of-load product line by introducing what is claimed to be the industry's first 100V synchronous buck regulator with integrated MOSFETs. The 600mA LM5017 is the first in a new family of step-down switching regulators that reduce PCB area and system cost while improving high-voltage reliability in telecommunication, industrial, smart grid and automotive systems. Used in conjunction with WEBENCH online design tool, the LM5017 simplifies high-voltage DC/DC conversion and speeds the design process.

The 600mA LM5017, together with the 300mA LM5018 and 100mA LM5019 available in April, enables direct point-of-load voltage regulation from input voltages as high as 100V. This eliminates external transient voltage suppressors or clamps required to achieve reliable operation in high-voltage applications. Integrated MOSFETs eliminate freewheeling Schottky diodes and improve efficiency. Pin-compatible 4x4mm LLP packaging offers a scalable solution that covers a wide range of power requirements. Constant on-time (COT) control architecture provides load transient response with no loop compensation required, further reducing the PCB area and simplifying the power supply design process.

The new switching regulators can also be used as isolated bias supplies for systems requiring small, efficient isolated power supplies. Unlike alternative flyback solutions, the LM5017 operates at switching frequencies up to 1MHz, dramatically reducing the size and cost of the transformer.

For applications that require fixed frequency operation, TI's 100V UCC25230 isolated bias supply switching converter supports up to 200mA output current, and uses a voltage mode control topology with input feed forward.

The LM5017 is currently available in volume, while the LM5018 and LM5019 will be out in the market by April. Offered in a thermally-enhanced 8-pin LLP package, the suggested retail price of the LM5017 is $1.65, LM5018 $1.40, and the LM5019 $1.25 in 1,000-unit quantities. The LM5017 in an 8-pin PSOP package will be available in March.



Texas Instruments, Inc.