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

The ST1PS01, a nano-quiescent step-down converter

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

面向隔离式降压调节器设计而优化的A6986IL6986I DC/DC转换器拥有宽泛的输入电压范围和低静态电流,确保能在最高5W的汽车工业应用中稳健运行且有效节能。






新型400 mA同步降压转换器,具有毫微静态电流和极高的效率,推动性能超越极限

意法半导体的微型ST1PS01ST1PS02ST1PS03降压转换器的静态电流仅为500 nA,针对电池供电和能量收集应用特别提供数字电压选择功能,能够在各种工作条件下实现高效率。




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.


eDesignSuite is a comprehensive set of easy-to-use design-aid utilities ready to help you streamline the system development process with a wide range of ST products.

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