Diodes Incorporated SDT40A120CTFP

Overview

SDT40A120CTFP from Diodes Incorporated is a 40A dual-leg trench Schottky rectifier in ITO-220AB package, rated for 120V reverse voltage per leg, with max 0.88V forward drop at 20A/25°C and 120µA reverse leakage at 120V/25°C. It serves as a high-efficiency freewheel or output rectifier in DC-DC converters and AC-DC adapters operating under high-temperature conditions.

For engineers reviewing the SDT40A120CTFP datasheet, SDT40A120CTFP pinout, SDT40A120CTFP application, or SDT40A120CTFP equivalent, key selection criteria include thermal resistance (4°C/W junction-to-case), soft switching behavior, low VF stability up to +125°C, and AEC-Q101 readiness for automotive power systems.

Technical Context

This dual-common-cathode Schottky rectifier integrates two independent 20A legs sharing one cathode terminal, enabling synchronous rectification or dual-output DC-DC topologies. Its trench MOS structure delivers lower VF than planar Schottkys while maintaining tight IR control across temperature.

The device operates within –55°C to +150°C junction range and exhibits soft reverse recovery with minimal ringing-critical for EMI-sensitive switch-mode supplies. Thermal performance is validated with a 50mm × 50mm × 23mm aluminum heatsink, supporting continuous 20A per leg at TC ≤ 85°C.

Key Specifications

Pinout & Package

Package: ITO-220AB - Insulated through-hole plastic package with integral heatsink tab, UL 94V-0 rated, matte tin-plated copper leadframe, 1.90g mass. Designed for mechanical isolation and simplified thermal interface in high-reliability power stages.

Key Features

Applications

Equivalent & Alternatives

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

Compared with VS-40CPH12 and MBR40120CT, SDT40A120CTFP uniquely balances ITO-220AB's compact insulated form factor, AEC-Q101 compliance, and best-in-class 125°C leakage performance-making it optimal for space-limited automotive and industrial DC-DC modules requiring long-term reliability.

Availability

SDT40A120CTFP is available at Aetrix Electronics and suitable for DC-DC converters, AC-DC adapters, and automotive body control modules requiring stable component supply, consistent thermal performance, and automotive-grade qualification.

Supply support for SDT40A120CTFP 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-efficiency power management, signal integrity, and protection solutions for industrial, automotive, and computing markets.

The SDT40A120CTFP belongs to Diodes' Trench Schottky Rectifier product line, engineered specifically for high-frequency, high-temperature power conversion where low VF, soft switching, and AEC-Q101 reliability are mandatory.

FAQ

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

The SDT40A120CTFP has a rated junction temperature range of –55°C to +150°C. This is validated per AEC-Q101 stress tests including High Temperature Reverse Bias (HTRB) at 150°C for 1000 hours and Temperature Cycling (TCT) over –55°C to +150°C for 1000 cycles, with electrical parameters monitored pre- and post-test.

Is the ITO-220AB package electrically insulated, and what is its creepage/clearance rating?

Yes, the ITO-220AB package features reinforced insulation between the metal tab and all three leads, certified to UL 94V-0 flammability and tested for dielectric strength ≥2500V RMS. Creepage and clearance meet IPC-2221 Class B requirements for 120V working voltage, enabling use in reinforced insulation safety architectures.

Does SDT40A120CTFP support paralleling of legs for higher current, and what layout guidance applies?

While the dual-leg configuration shares a common cathode, paralleling legs is not recommended due to mismatched thermal paths and potential current imbalance. For >20A per path, use separate devices with matched layout: identical trace length/width, symmetric thermal vias to inner copper planes, and shared heatsink contact area.

How does the soft switching behavior impact EMI in high-frequency designs?

Soft switching eliminates reverse recovery charge (Qrr), preventing abrupt current collapse and associated voltage spikes. In 300kHz flyback converters, this reduces peak-to-peak noise on the primary switch node by ≥8dB and cuts common-mode EMI above 30MHz by 12dB, easing CISPR-22 Class B compliance.