STMicroelectronics STPS3L25S

Overview

STPS3L25S from STMicroelectronics is a single low-drop Schottky rectifier optimized for synchronous rectification in 3.3 V switched-mode power supplies and high-frequency DC/DC converters, with IF(AV) = 3 A, VRRM = 25 V, VF(max) = 0.44 V at Tj = 125°C, and avalanche-rated PARM = 1500 W (tp = 1 µs), used as antiparallel diode across secondary-side freewheel MOSFETs.

For engineers reviewing the STPS3L25S datasheet, STPS3L25S pinout, STPS3L25S application, or STPS3L25S equivalent, key selection criteria include forward voltage drop at 3 A/125°C, thermal resistance Rth(j-l) = 20 °C/W, SMC package compatibility, avalanche energy handling, and reverse leakage <30 mA at 125°C under VRRM.

Technical Context

This Schottky rectifier employs a planar silicon junction with metal–semiconductor contact to achieve ultra-low conduction loss and fast recovery without minority-carrier storage. Its 25 V blocking rating and 75 A non-repetitive surge capability support robust operation in compact, high-efficiency 3.3 V output stages.

The device is characterized for δ = 0.5 duty cycle and TL = 115°C, with thermal runaway avoided only when dPtot/dTj < −1 on heatsink. Junction-to-lead thermal resistance of 20 °C/W enables direct PCB copper pad cooling without external heatsink in many SMPS layouts.

Key Specifications

Pinout & Package

STPS3L25S is housed in an SMC (DO-214AB) surface-mount package: cathode-indicated by black band, lead material is matte tin-plated copper, and body dimensions are 8.15 × 6.25 × 2.45 mm (L × D × A2 max). Thermal path relies on soldered leads to PCB copper.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Schottky rectifier applications.

Compared with SB325 and VS-3EJH02-M3, STPS3L25S delivers the lowest VF at high temperature and best lead-based thermal coupling, making it optimal for high-density, thermally constrained 3.3 V SMPS where conduction loss and junction temperature control are primary design drivers.

Availability

STPS3L25S is available at Aetrix Electronics and suitable for server VRMs, industrial DC/DC converters, telecom PoE PD modules, and automotive infotainment power supplies requiring stable component supply and long-term manufacturability.

Supply support for STPS3L25S includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

STPS3L25S belongs to ST's low-voltage Schottky rectifier product line, engineered specifically for high-efficiency, high-frequency synchronous rectification in sub-5 V DC/DC conversion stages.

FAQ

What is the maximum junction temperature and how is it enforced?

The absolute maximum junction temperature is 150°C, verified per JEDEC JESD22-A103. Operation beyond this limit risks irreversible degradation of the Schottky barrier. Designers must use Rth(j-l) = 20 °C/W and measured lead temperature to infer Tj - not ambient - and ensure thermal design maintains Tj ≤ 150°C under worst-case load and ambient conditions.

Can STPS3L25S replace a standard PN diode in an existing 3.3 V SMPS design?

Yes, but only if the original design accommodates lower VF and higher dV/dt. The STPS3L25S has no reverse recovery charge (Qrr ≈ 0), eliminating switching losses present in PN diodes. However, its higher capacitance (≈100 pF at 0 V) may require gate drive strength verification to avoid ringing in synchronous MOSFETs.

Is the SMC package lead-free and RoHS compliant?

Yes. STPS3L25S is manufactured with matte tin-plated leads and complies with RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006. The epoxy molding compound meets UL94 V-0 flammability rating, and the full device is qualified per AEC-Q101 for stress testing, though not automotive-grade qualified.

How is avalanche capability tested and what does PARM = 1500 W mean in practice?

PARM is measured per JEDEC JESD22-A110 using a 1 µs unclamped inductive switch-off test at Tj = 25°C. A 1500 W rating means the device can absorb up to 1.5 mJ (1500 W × 1 µs) of transient energy without failure - sufficient to clamp typical 30–50 V overshoot spikes during MOSFET turn-off in 3.3 V output stages.