STMicroelectronics STPST5H100UF

Overview

STPST5H100UF from STMicroelectronics is a 5 A, 100 V Schottky trench rectifier in SMB Flat package, optimized for high-frequency SMPS with low conduction and switching losses. It features 0.550 V typical forward voltage at 5 A/125 °C, 175 °C max junction temperature, and avalanche-tested ruggedness. Used in auxiliary power supplies for telecom and smart metering systems.

For engineers reviewing the STPST5H100UF datasheet, STPST5H100UF pinout, STPST5H100UF application, or STPST5H100UF equivalent, key selection criteria include VF/IR trade-off at high Tj, thermal resistance (Rth(j-l) = 7.7 °C/W), flat-package PCB space savings, and ECOPACK2 compliance for RoHS- and REACH-compliant designs.

Technical Context

This device employs ST's proprietary trench Schottky technology to achieve superior forward voltage versus reverse leakage performance across temperature - typ. VF = 0.550 V at 5 A/125 °C and IR = 1.0 mA at 70 V/125 °C. Its low Qrr and soft recovery reduce EMI and switching losses in flyback and DC/DC topologies.

The SMB Flat package enables direct thermal conduction via leads (Rth(j-l) = 7.7 °C/W), supporting high-power density designs without heatsinks up to 5 A average current at TL = 135 °C. Avalanche rating (IAS = 9 A, L = 300 µH) ensures robustness under unclamped inductive switching.

Key Specifications

Pinout & Package

SMB Flat package: surface-mount, 2-terminal, lead-free, UL94 V0 epoxy body (3.30–3.95 mm D, 5.10–5.60 mm E), optimized for automated assembly and thermal conduction through soldered leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SS5H10 and SB5100, STPST5H100UF delivers 24% lower conduction loss at 125 °C, 9 A avalanche immunity for fault tolerance, and 81% lower junction-to-lead thermal resistance - directly enabling smaller PCB area and higher power density in auxiliary SMPS.

Availability

STPST5H100UF is available at Aetrix Electronics and suitable for telecom auxiliary supplies, smart metering power stages, LED driver bias rails, and flyback DC/DC converters requiring stable component supply and long lifecycle support.

Supply support for STPST5H100UF 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 microcontrollers, power devices, sensors, and analog ICs for industrial, automotive, and consumer markets.

The STPST5H100UF belongs to ST's trench Schottky rectifier product line, engineered specifically for high-frequency, high-efficiency switched-mode power supplies where low VF, high Tj, and avalanche ruggedness are critical.

FAQ

What is the maximum allowable case temperature for continuous operation?

The SMB Flat variant (STPST5H100UF) is rated for IF(AV) = 5 A at TL = 135 °C - meaning the lead temperature must not exceed 135 °C under steady-state conditions. This corresponds to a typical case temperature of ≤125 °C depending on PCB copper area and airflow. Exceeding this limit risks thermal runaway due to the (dPtot/dTj) < (1/Rth(j-a)) condition.

Does STPST5H100UF require a heatsink in a 5 A application?

No heatsink is required if PCB layout provides ≥60 cm² of 70 µm copper per lead (per Figure 12), achieving Rth(j-a) ≈ 3.5 °C/W. With SMB Flat's Rth(j-l) = 7.7 °C/W and 5 A conduction (P ≈ 2.75 W), junction rise is ~21 °C above lead temperature - well within the 175 °C Tj limit when TL ≤ 135 °C.

How does its avalanche rating compare to standard Schottky diodes?

Unlike conventional Schottky diodes - which lack controlled avalanche capability - STPST5H100UF is fully tested to IAS = 9 A (L = 300 µH, VDD = 15 V). This enables safe clamping of inductive energy in freewheeling and OR-ing configurations where voltage overshoot would otherwise destroy unprotected devices.

Is STPST5H100UF compatible with lead-free reflow profiles?

Yes - the SMB Flat package is lead-free and qualified for standard JEDEC J-STD-020D reflow profiles, including peak temperatures up to 260 °C for 10 seconds. The UL94 V0 epoxy body remains dimensionally stable and mechanically sound under repeated thermal cycling.