STMicroelectronics STPS20120CT

Overview

STPS20120CT from STMicroelectronics is a dual common-cathode Schottky rectifier in TO-220AB package, rated for 120 V reverse voltage and 2 × 10 A average forward current per diode at Tc = 150 °C, with typical forward voltage of 0.70 V at 2.5 A and 25 °C. It delivers low conduction loss and avalanche-rated ruggedness for high-frequency SMPS in notebook/LCD adapters and desktop power supplies.

For engineers reviewing the STPS20120CT datasheet, STPS20120CT pinout, STPS20120CT application, or STPS20120CT equivalent, key selection criteria include junction-to-case thermal resistance (3 °C/W per diode), peak surge current (150 A), leakage current (≤5 mA at 125 °C), and ECOPACK®2 compliance - all critical for thermal management and reliability in compact AC/DC converters.

Technical Context

This dual Schottky rectifier integrates two independent anodes sharing a common cathode terminal, enabling synchronous or interleaved operation in center-tapped or full-wave bridge configurations. Its low VF–IR trade-off targets efficiency-sensitive 100–200 kHz SMPS topologies where thermal derating and reverse recovery are non-factors.

The device features specified avalanche capability (330 W, tp = 10 µs) and maximum junction temperature of 175 °C, allowing operation under transient overvoltage stress without external snubbers. Thermal coupling between diodes is quantified (Rth(c) = 0.6 °C/W), supporting accurate multi-diode junction temperature modeling in shared heatsink layouts.

Key Specifications

Pinout & Package

STPS20120CT uses the TO-220AB package (3-pin, straight leads), with metal tab electrically connected to the common cathode. The package provides low thermal resistance and mechanical robustness for bolt-down heatsinking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with VS-20CPH12 and MUR20120CT, STPS20120CT offers the best balance of VF, IR, and thermal resistance in TO-220AB - making it optimal for cost-sensitive, volume desktop and adapter designs requiring proven field reliability and ECOPACK®2 compliance.

Availability

STPS20120CT is available at Aetrix Electronics and suitable for notebook AC adapters, LCD monitor power supplies, and desktop PC SMPS requiring stable component supply and long-term production continuity.

Supply support for STPS20120CT 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 microcontrollers, power devices, sensors, and analog ICs for automotive, industrial, and consumer markets.

The STPS series targets high-efficiency, high-reliability power conversion - specifically engineered for Schottky rectification in switched-mode power supplies where low VF, controlled IR, and rugged avalanche behavior are mandatory.

FAQ

Is STPS20120CT pin-compatible with other TO-220AB dual Schottky rectifiers?

Yes - STPS20120CT follows standard TO-220AB pinout: Pin 1 = Anode 1, Pin 2 = Anode 2, Pin 3 = Common Cathode/Tab. This matches industry-standard dual common-cathode rectifiers including MUR20120CT and SB20120CT, enabling direct PCB replacement where thermal and electrical specs align.

What is the maximum recommended heatsink thermal resistance for continuous 20 A total output?

At 20 A total (10 A per diode), power dissipation is ~7 W per diode (using P = 0.62×IF + 0.012×IF²). With Rth(j-c) = 3 °C/W and max Tj = 175 °C, ambient must stay ≤65 °C when using a heatsink with Rth(c-a) ≤ 12 °C/W - verified via thermal simulation using coupled Rth(c) = 0.6 °C/W between diodes.

Does STPS20120CT require a thermal pad or insulator when mounted to a heatsink?

Yes - the metal tab is electrically connected to the common cathode. If the heatsink is grounded, an electrically isolating but thermally conductive pad (e.g., mica or polymer-based) must be used. Mounting torque must not exceed 0.7 N·m to avoid die cracking or solder joint fatigue.

Can STPS20120CT be used in place of a single 20 A Schottky like STPS20L120CG?

No - STPS20L120CG is a single-anode 20 A device in D²PAK; STPS20120CT is dual-anode 10 A per diode. They differ in circuit function: the former serves single-rail rectification, the latter enables dual-rail or center-tapped topologies. Substitution would require redesigning the transformer secondary and PCB layout.