STMicroelectronics STPS20L40CFP

Overview

STPS20L40CFP from STMicroelectronics is a dual-center-tap low-drop Schottky rectifier in TO-220FPAB insulated package, rated for 40 V repetitive peak reverse voltage, 2 × 10 A average forward current per diode, and maximum junction temperature of 150 °C. It delivers VF(max) = 0.5 V at 10 A/25 °C and supports high-frequency SMPS, DC-DC converters, and polarity protection circuits.

For engineers reviewing the STPS20L40CFP datasheet, STPS20L40CFP pinout, STPS20L40CFP application, or STPS20L40CFP equivalent, key selection criteria include its dual-diode configuration with isolated case (200 V insulation), low conduction loss (VF ≤ 0.73 V @ 20 A/25 °C), avalanche-rated capability (4000 W @ 1 µs), and thermal resistance Rth(j-c) = 4.5 °C/W per diode.

Technical Context

This device integrates two independent Schottky diodes sharing a common cathode terminal (K) and separate anode terminals (A1, A2), enabling center-tapped transformer secondary rectification or dual-channel freewheeling. Its low barrier height yields minimal forward voltage drop and negligible minority-carrier storage, eliminating reverse recovery time.

The TO-220FPAB package provides electrical isolation between the metal tab and internal die, supporting safe mounting on heatsinks without insulating washers. Thermal coupling between diodes is characterized by Rth(c) = 3.5 °C/W (total) and Rth(j-c) = 4.5 °C/W per diode under specified test conditions.

Key Specifications

Pinout & Package

TO-220FPAB is an insulated variant of TO-220 with electrically isolated metal tab (200 V DC isolation, 12 pF capacitance). Mounting torque: 0.55 Nm recommended (max 0.70 Nm).

Key Features

Applications

Equivalent & Alternatives

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

Compared with STPS20L40CFP, STPS20L45CGY offers higher reverse voltage with minor VF trade-off, while VS-20CPH04 lacks dual-anode integration and insulation-making it unsuitable for compact, isolated center-tap designs without layout changes.

Availability

STPS20L40CFP is available at Aetrix Electronics and suitable for server VRM output stages, industrial DC-DC converters, and automotive body control modules requiring stable component supply and long-term lifecycle support.

Supply support for STPS20L40CFP 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-frequency power conversion with Schottky technology optimized for low-voltage, high-current rectification in SMPS and DC-DC applications.

FAQ

Is STPS20L40CFP still in active production?

No-STMicroelectronics marked STPS20L40CFP as obsolete in March 2007 per revision history. However, Aetrix Electronics maintains legacy inventory with full traceability and supports design continuity through controlled allocation and cross-reference guidance for qualified replacements.

Can STPS20L40CFP be used in surface-mount designs?

No-it uses the through-hole TO-220FPAB package with three leads and a metal tab requiring mechanical screw mounting. It is incompatible with SMT reflow or wave soldering processes and must be installed using manual or selective soldering with torque-controlled fastening.

What is the maximum allowable case temperature during continuous operation?

The datasheet specifies IF(AV) = 10 A per diode at Tc = 115 °C with duty cycle δ = 0.5. Exceeding 115 °C case temperature reduces current rating nonlinearly; sustained operation above 125 °C case requires derating per Figure 2 and thermal modeling using Rth(j-c) = 4.5 °C/W.

Does the insulated tab eliminate all need for thermal interface material?

The TO-220FPAB tab provides 200 V DC isolation but does not replace thermal interface material. A thermally conductive paste or pad is still required between tab and heatsink to minimize Rth(c-hs); omission increases total thermal resistance and risks junction overheating at rated current.