STMicroelectronics STPS3L45AF

Overview

STPS3L45AF from STMicroelectronics is a 3 A average forward current, 45 V repetitive peak reverse voltage power Schottky rectifier in SMAflat (non-exposed pad) package, featuring 0.462 V typical forward voltage at 3 A and 25 °C, low thermal resistance (15 °C/W junction-to-lead), and specified avalanche capability - optimized for compact AC/DC chargers and high-frequency DC-DC converters.

For engineers reviewing the STPS3L45AF datasheet, STPS3L45AF pinout, STPS3L45AF application, or STPS3L45AF equivalent, key selection criteria include forward voltage drop at operating temperature, reverse leakage at 125 °C, avalanche energy rating (70 W, tp = 10 µs), thermal resistance, and SMAflat footprint compatibility with space-constrained PCB layouts.

Technical Context

This Schottky rectifier employs a planar metal-silicon junction structure to achieve negligible switching losses and low forward conduction loss - critical for >100 kHz SMPS topologies. Its 150 °C maximum junction temperature and 15 °C/W R_th(j-l) enable direct lead-mount thermal management without heatsinks in low-power adapters.

The device supports repetitive avalanche operation up to 50 V peak (V_ARM) and 70 W pulse power, validated per ST Application Notes AN1768 and AN2025. Reverse leakage remains below 135 mA at 125 °C and full 45 V reverse bias - enabling stable performance in thermally demanding secondary-side rectification.

Key Specifications

Pinout & Package

Package: SMAflat (non-exposed pad), surface-mount, UL94 V0 epoxy, lead-free, 0.035 g unit weight. Dimensions: 5.60 × 3.44 × 1.10 mm (E × E1 × A max).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MBR345F-E3/45 and SS34H, STPS3L45AF uniquely combines 45 V blocking, 0.462 V low V_F, 70 W avalanche power, and ultra-compact SMAflat footprint - making it optimal for space- and efficiency-critical 20–30 W adapter designs where thermal and transient robustness are co-prioritized.

Availability

STPS3L45AF is available at Aetrix Electronics and suitable for USB-C wall adapters, industrial IoT power modules, medical portable chargers, and automotive accessory DC-DC converters requiring stable component supply across multi-year production cycles.

Supply support for STPS3L45AF 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, Switzerland, designing and manufacturing analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

The STPS series targets high-efficiency, high-reliability power conversion - specifically engineered for compact, thermally constrained AC/DC and DC-DC applications where Schottky performance and avalanche ruggedness are mandatory.

FAQ

Is STPS3L45AF suitable for synchronous rectification circuits?

No - STPS3L45AF is a passive Schottky rectifier, not a synchronous rectifier IC. It replaces MOSFET-based synchronous rectifiers in simpler designs but requires no gate drive. Its zero reverse recovery enables clean operation alongside controllers like STSR3 or UCC24612, but it does not integrate control logic or drivers.

What is the maximum allowable PCB copper area for thermal performance?

Per Figure 10, thermal resistance junction-to-ambient drops to ~45 °C/W with 5 cm² total copper (2.5 cm² per lead). For optimal thermal performance without forced air, use ≥3 cm² of 35 µm copper per lead, connected via multiple thermal vias to inner layers if board stack-up permits.

Does STPS3L45AF meet automotive AEC-Q101 requirements?

No - STPS3L45AF is not AEC-Q101 qualified. ST's automotive-grade equivalents include STPS3H45S (AEC-Q101 qualified, same V_RRM/I_F, but in SMA package with exposed pad and extended temperature screening).

How is avalanche energy measured for STPS3L45AF?

Avalanche energy is measured per ST Application Note AN1768: applying controlled 10 µs pulses at 125 °C junction temperature while monitoring V_ARM and I_AR; the 70 W rating corresponds to (V_ARM × I_AR) under defined test conditions, validated across production lots using standardized waveform generators and calorimetric verification.