ST1S31PUR

Voltage Regulators - DC DC Switching Regulators Overview

The ST1S31PUR is a synchronous step-down DC-DC converter from STMicroelectronics, housed in an 8-lead VFDFPN-EP package. It operates with an input voltage range of 2.8 V to 5.5 V and provides an adjustable output voltage starting from 0.8 V up to the input level. The device delivers a continuous DC output current of 3 A at a fixed switching frequency of 1.5 MHz. Key electrical specifications include a quiescent current of 630 uA and integrated power MOSFETs with on-resistances of 60 mΩ for the high-side switch and 45 mΩ for the synchronous rectifier. It supports operation across a temperature range of -40°C to +150°C.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Internally compensated peak current mode control minimizes external component count for compact designs.
• Integrated high-efficiency power switches enable stable performance with all-ceramic capacitor configurations.
• Built-in protection mechanisms include cycle-by-cycle current limiting and current foldback short-circuit protection.
• Features internal soft-start and Power Good (POR) signal generation for reliable system sequencing.

Voltage Regulators - DC DC Switching Regulators Applications

• Portable consumer electronics requiring efficient power management
• Industrial embedded systems utilizing single-output regulation
• Automotive infotainment and sensor nodes within specified voltage ranges
• Demonstration boards for validating buck converter topologies

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify that the specific suffix PUR corresponds to the VFDFPN-EP-8 package and tape-and-reel delivery format as listed in official distributor catalogs. Confirm RoHS compliance status through the manufacturer's latest documentation before integration. Ensure the ordering part number matches the exact thermal and electrical characteristics required for the target application environment.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this regulator when a 3 A output current is required from a low-voltage input source between 2.8 V and 5.5 V. The 1.5 MHz frequency allows for smaller passive components compared to lower-frequency alternatives. Consider the internal compensation feature if minimizing bill-of-materials complexity is a priority. Evaluate the thermal performance of the exposed pad package for high-duty-cycle applications.

Voltage Regulators - DC DC Switching Regulators Part Context

The ST1S31 belongs to STMicroelectronics' portfolio of monolithic buck converters designed for high reliability in automotive and industrial sectors. It complements other PMIC solutions by offering a balance of high current density and simplified design through internal compensation. The device is part of a broader family of synchronous step-down regulators optimized for efficiency and compact footprint requirements.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

Direct functional substitutes may include other 3 A synchronous buck regulators from STMicroelectronics or competitors with similar input/output voltage ranges and 1.5 MHz switching frequencies. Verify pin compatibility and thermal resistance values when considering alternative packages. Review datasheets for differences in quiescent current and protection features to ensure system stability.