STMicroelectronics

ST1S31D-R

ST1S31D-R Description

The ST1S31D-R from STMicroelectronics is a high-efficiency, 3A adjustable synchronous buck regulator designed for compact, power-sensitive applications. Operating within an input voltage range of 2.8V to 5.5V, it delivers an adjustable output voltage from 0.8V to 5.5V, making it versatile for low-voltage systems. With a 1.5MHz switching frequency, it minimizes external component size while maintaining high efficiency. The device integrates a synchronous rectifier, reducing power dissipation and improving thermal performance. Packaged in an 8-pin SOIC, it is ideal for space-constrained designs. Although marked as obsolete, it remains a reliable choice for legacy systems requiring stable, high-current power conversion.

ST1S31D-R Features

• Adjustable Output (0.8V–5.5V): Flexible voltage regulation for diverse applications.
• High Efficiency: Synchronous rectification minimizes losses, enhancing thermal management.
• Compact Design: 1.5MHz switching frequency allows for smaller inductors and capacitors.
• Wide Input Range (2.8V–5.5V): Suitable for battery-powered and regulated DC supply systems.
• 3A Output Current: Robust current delivery for demanding loads.
• Surface-Mount (SOIC-8): Space-saving footprint for PCB integration.
• RoHS3 & REACH Compliant: Meets environmental and regulatory standards.

ST1S31D-R Applications

• Portable Electronics: Power management in handheld devices, IoT sensors, and wearables.
• Embedded Systems: Voltage regulation for microcontrollers, FPGAs, and low-power processors.
• Industrial Automation: Reliable power supply for control modules and sensors.
• Consumer Electronics: Efficient DC-DC conversion in compact gadgets.
• Legacy Systems: Maintenance and repair of older designs requiring obsolete components.

Conclusion of ST1S31D-R

The ST1S31D-R excels in high-efficiency, compact power conversion, offering a balance of performance and integration. Its synchronous buck topology and wide adjustability make it suitable for both battery-operated and line-powered systems. While obsolete, its 3A output, small footprint, and compliance with environmental standards ensure it remains a viable option for specific use cases. Engineers seeking a proven, space-efficient regulator for low-voltage applications will find this IC a dependable solution.