Buck Regulators

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A buck converter also called buck regulator or DC-DC step-down switching regulator, is a type of DC-DC converter which provides an output regulated voltage that is lower than its input voltage.

ST's monolithic step-down (buck) converter ICs offer input-voltage capability up to 61 V, deliver output currents up to 4 A, with high switching frequency. This broad portfolio of ICs is composed of highly-specialized products to meet every market requirement:

  • High-voltage technology together with high reliability, robustness and compactness for industrial and automotive applications
  • High efficiency at any load and a high level of performance for consumer and computer products

These buck regulators embed a full set of protection functions (overcurrent, overvoltage, over-temperature) to increase the MTBF and reduce the number of external components.

buck converter regulator ic Monolithic buck converter ICs (buck regulator) for any application requirement

There are multiple package options, all offering compactness and high thermal performances.

Featured buck converters

buck converter l6981

L6981 38 V 1.5 A buck converter with low quiescent current

buck converter l6982

L6982 38 V 2 A buck converter with low quiescent current

Wide range of step-down (buck) switching regulators

Learn about ST broad selection of buck converters, designed to meet a wide range of application requirements.

Low quiescent current buck converter ICs

ST's low IQ buck converters are ideal for any power-budgeted applications, such as battery-powered devices or green-compliant equipment with long stand-by operation. Extend the battery life and reduce the overall power consumption of your industrial and automotive application designs.

Isolated buck converters

Reduce Bill-Of-Materials costs in Automotive and Industrial applications.

Synchronous buck converter ICs

For high efficiency and small size solutions.

Buck converters for Industrial applications

industrial buck converters
Energy saving DC-DC buck converters for industrial

High reliability and excellent robustness buck converters, for industrial and any application requiring a wide range of input output voltages.

See all Industrial buck converters

Buck converters for Automotive applications

automotive buck converters
High-performance automotive DC-DC buck converters

ST offers high performance and high flexibility AEC-Q100 compliant buck converters for automotive applications.

See all Automotive buck converters

Start your design

buck converter design tool

How to choose the right DC-DC switching regulator?

buck converter pdf reference guide

L6983 /2 /1 Integrated synchronous regulator
DC/DC converters
L7983 - Compact 60 V 300 mA
DC/DC converter
The ST1PS01, a nano-quiescent step-down converter

New Isolated Buck Converters Reduce Bill-of-Materials Costs in Automotive and Industrial Applications

Optimized for isolated buck regulator designs, the new A6986I and L6986I DC/DC converters boast a wide input-voltage range and low quiescent current to ensure robust and energy-efficient operation in automotive and industrial applications up to 5W.

The isolated buck topology drastically lowers the bill of materials in systems that require a regulated non-isolated primary voltage and one or more isolated secondary voltages.


Evaluation boards are also available to help developers build and verify their designs.



New 400 mA synchronous buck converters, with nano-quiescent current and very high efficiency, push performance beyond limits

Boasting a quiescent current of only 500 nA, ST’s miniaturized ST1PS01ST1PS02 and ST1PS03 step-down converters with digital voltage selection specifically address battery-powered and energy-harvesting applications, thanks also to their high efficiency over a wide range of operating conditions.

The integrated power switch and compensation network allow this new generation of step-down converters to work with only just a few external components.

Evaluation boards are available for the three products, to support developers in their designs.


New 61 V, 3 A step-down switching regulator for automotive application

Housed in a HTSSOP16-package, the A7987 is a 3 A step-down switching regulator with a wide input-voltage range, making it suitable for 24 V battery-powered applications.

Specifically recommended to design flexible and robust solutions, the A7987 also offers a set of additional functionalities including adjustable current limit, synchronization with a 180° phase shift, and power sequencing.

These key features ensure flexible and stable performance when several voltage rails are powered up in automotive applications such as body infotainment and telematics.

Large selection of step-down DC-DC regulators with synchronous rectification

In the quest for higher efficiency and compact form factor in their DC-DC supply designs, engineers now have a few more allies: the L6985FL6986F and L6986 step-down DC-DC regulators with synchronous rectification and an output current of 0.5 A, 1,5 A and 2 A respectively.
Based on a peak current mode architecture with a p-channel power MOSFET, they feature a selectable low-consumption-mode (LCM burst mode) to increase efficiency at light load, and a low-noise-mode (LNM with fixed PWM switching frequency) for noise-sensitive designs.

An easy-to-use evaluation board (STEVAL-ISA156V1) based on the L6986 regulator is available to help you configure and evaluate application parameters so you can reach higher efficiency, higher power density and lower standby power designs.


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