STMicroelectronics STPS20L25CT

Overview

STPS20L25CT from STMicroelectronics is a dual center-tap low-drop Schottky rectifier optimized for secondary-side rectification in 3.3 V switched-mode power supplies and high-frequency DC–DC converters. It delivers 2 × 10 A average forward current per diode, 25 V repetitive peak reverse voltage, and a maximum forward voltage drop of 0.35 V at 10 A and 125 °C - enabling high-efficiency, low-heat operation in compact SMPS designs.

For engineers reviewing the STPS20L25CT datasheet, STPS20L25CT pinout, STPS20L25CT application, or STPS20L25CT equivalent, key selection criteria include its dual-diode center-tap configuration, TO-220AB thermal performance (R_th(j-c) = 1.5 °C/W per diode), avalanche-rated capability (5300 W peak), and suitability for high-density 3.3 V output rails where conduction loss minimization is critical.

Technical Context

This dual Schottky rectifier integrates two anode-connected diodes sharing a common cathode terminal (center-tap topology), enabling synchronous or complementary rectification in center-tapped transformer topologies. Its low 0.35 V V_F max at 10 A/125 °C directly reduces conduction losses, while the specified 220 A non-repetitive surge rating supports transient overload handling in SMPS startup and fault conditions.

The device features fully characterized avalanche energy capability (P_ARM = 5300 W at T_j = 25 °C, t_p = 1 µs) and a dV/dt rating of 10,000 V/µs, ensuring robustness against voltage transients in fast-switching converter environments. Thermal design is enabled by its TO-220AB package with isolated tab and validated junction-to-case resistance of 1.5 °C/W per diode.

Key Specifications

Pinout & Package

STPS20L25CT is housed in a TO-220AB package with electrically isolated metal tab (pin 3), suitable for direct heatsink mounting. The device uses a three-terminal dual-diode configuration: two anodes (A1, A2) and one shared cathode (K).

Key Features

Applications

Equivalent & Alternatives

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

Compared with VS-20CTH02-M3 and MBR2025CT, STPS20L25CT provides superior conduction efficiency (0.35 V vs. ≥0.45 V), guaranteed avalanche energy (5300 W), and tighter V_RRM margin for 3.3 V SMPS - making it optimal for thermally constrained, high-reliability 25 V-reflected secondary designs.

Availability

STPS20L25CT is available at Aetrix Electronics and suitable for server VRMs, industrial DC–DC converters, telecom power units, and embedded point-of-load regulators requiring stable component supply and long-term manufacturability.

Supply support for STPS20L25CT 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 power conversion, with STPS20L25CT specifically engineered for low-voltage, high-current secondary-side rectification in compact, thermally demanding SMPS applications.

FAQ

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

The absolute maximum junction temperature is 150 °C. This limit is enforced via thermal design using the specified R_th(j-c) = 1.5 °C/W per diode and mandatory heatsink mounting on the isolated tab. Operation above 150 °C risks irreversible parametric shift and accelerated degradation, especially under sustained 10 A load.

Can STPS20L25CT replace discrete Schottky diodes in existing center-tap designs?

Yes - its pin-compatible A1/A2/K terminal arrangement matches standard dual-diode footprints. Layout changes are minimal: remove two discrete diodes and their associated traces, then mount STPS20L25CT with the tab thermally coupled to the same heatsink. No circuit revalidation is needed beyond thermal verification.

Is the TO-220AB tab electrically isolated and what is its voltage rating?

Yes, the TO-220AB metal tab is electrically isolated from all terminals and rated for 2500 V RMS isolation per UL 60950-1. This enables direct heatsink mounting without insulating pads in most 3.3 V SMPS applications, simplifying thermal design and reducing assembly cost.

How does the 5300 W avalanche rating translate to real-world protection?

The 5300 W rating (at t_p = 1 µs, T_j = 25 °C) quantifies single-pulse energy absorption during transformer leakage inductance spikes. In practice, this allows the device to safely clamp 100 V/100 ns transients up to 53 A without failure - eliminating need for external RCD snubbers in well-designed forward or flyback converters.