Toshiba Semiconductor and Storage TK20A25D,S5Q(M

Overview

TK20A25D from Toshiba is a silicon N-channel power MOSFET in the π-MOSⅣ family, designed as a high-current switching device for DC-DC converters and motor drives. It delivers 20 A continuous drain current at 250 V V_DSS, with R_DS(ON) = 0.073 Ω (typ.) at V_GS = 10 V and operates up to 150 °C channel temperature.

For engineers reviewing the TK20A25D datasheet, TK20A25D pinout, TK20A25D application, or TK20A25D equivalent, key selection criteria include its TO-220SIS package thermal performance (R_th(ch-c) = 2.78 °C/W), avalanche energy rating (E_AS = 120 mJ), and gate threshold voltage range (1.5–3.5 V) for reliable drive compatibility with 3.3 V/5 V logic.

Technical Context

The TK20A25D employs a planar vertical DMOS structure optimized for low conduction loss and robust unclamped inductive switching (UIS). Its enhancement-mode operation ensures zero gate current in steady state, while the integrated body diode supports freewheeling in buck and half-bridge topologies.

Thermal design centers on channel-to-case conduction via the TO-220SIS metal tab (isolated mounting), with guaranteed safe operating area (SOA) up to 20 A at 100 V for 10 ms. Dynamic parameters-including C_iss = 2550 pF, Q_g = 55 nC, and t_on/t_off = 60/270 ns-support efficient hard-switching below 100 kHz.

Key Specifications

Pinout & Package

Package: TO-220SIS (JEITA SC-67, Toshiba 2-10U1S), isolated metal tab, 1.7 g weight, RoHS-compliant marking.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar N-channel power MOSFET applications.

Compared with STP20NM50FP and IRFZ44NPBF, the TK20A25D uniquely combines 250 V rating, 120 mJ avalanche energy, TO-220SIS isolation, and logic-level gate drive-making it optimal for space-constrained, safety-critical 200 V-class switching applications where thermal management and reliability under inductive stress are prioritized.

Availability

TK20A25D is available at Aetrix Electronics and suitable for switching voltage regulators, motor drive outputs, DC-DC converters, and uninterruptible power systems requiring stable component supply across industrial and embedded production cycles.

Supply support for TK20A25D 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

Toshiba Electronic Devices & Storage Corporation designs and manufactures discrete semiconductors, power devices, and logic ICs for industrial, automotive, and consumer applications.

The TK20A25D belongs to Toshiba's π-MOSⅣ power MOSFET product line, engineered for high-efficiency, high-reliability switching in medium-voltage power conversion systems up to 250 V.

FAQ

What is the maximum continuous drain current rating for the TK20A25D?

The TK20A25D has a maximum continuous drain current (I_D) of 20 A at case temperature T_c = 25 °C. This rating assumes proper heatsinking and derating per the R_th(ch-c) = 2.78 °C/W specification. At higher case temperatures, the current must be reduced linearly to maintain channel temperature ≤150 °C, as defined in the absolute maximum ratings table.

Does the TK20A25D have an isolated package, and what is its isolation voltage rating?

Yes, the TK20A25D uses the TO-220SIS package with electrically isolated metal tab. Its isolation voltage rating is 2000 V_RMS, verified per safety standards. This allows direct mounting to a grounded heatsink without additional insulation, simplifying thermal design in high-voltage systems where creepage and clearance are critical.

What is the typical gate threshold voltage range for the TK20A25D, and how does it affect drive requirements?

The TK20A25D has a gate threshold voltage (V_th) range of 1.5 to 3.5 V at V_DS = 10 V and I_D = 1 mA. This logic-level characteristic means the TK20A25D fully enhances with standard 3.3 V or 5 V microcontroller outputs or gate drivers, eliminating the need for external level shifters in most low-to-medium frequency switching applications.

How much avalanche energy can the TK20A25D withstand, and under what test conditions?

The TK20A25D is rated for 120 mJ single-pulse avalanche energy (E_AS) under test conditions of V_DD ≈ 50 V, T_ch = 25 °C (initial), L = 0.5 mH, R_G = 25 Ω, and I_AR = 20 A. This validated ruggedness enables reliable operation in inductive switching circuits-such as motor drives and SMPS-without requiring external avalanche clamps.

What is the thermal resistance from channel to case (R_th(ch-c)) for the TK20A25D, and why is it important?

The TK20A25D has a maximum channel-to-case thermal resistance (R_th(ch-c)) of 2.78 °C/W. This low value directly determines how much power can be safely dissipated through the metal tab into an external heatsink. For example, with a 40 °C heatsink temperature rise, the TK20A25D can dissipate over 14 W continuously-critical for maintaining reliability in compact, high-power-density designs.