Diodes Incorporated DMTH4008LFDFW-7

Overview

DMTH4008LFDFW from Diodes Incorporated is a 40V, N-channel enhancement-mode MOSFET in U-DFN2020-6 package, rated for continuous drain current of 11.6A at 25°C and 8.2A at 100°C, with R_DS(ON) of 11.5mΩ @ V_GS=10V and 18mΩ @ V_GS=4.5V, designed for high-efficiency DC-DC converters and automotive-grade power management.

For engineers reviewing the DMTH4008LFDFW datasheet, DMTH4008LFDFW pinout, DMTH4008LFDFW application, or DMTH4008LFDFW equivalent, this device supports +175°C operation, 100% unclamped inductive switching qualification, and low-profile (0.6mm) mounting-critical for space-constrained, thermally demanding power stages in automotive and industrial systems.

Technical Context

This MOSFET employs trench-gate silicon technology optimized for simultaneous low conduction loss and fast switching, with gate charge values of 6.8nC (V_GS=4.5V) and 14.2nC (V_GS=10V), enabling efficient operation in synchronous buck topologies up to several hundred kHz.

Its thermal design supports junction-to-case resistance of 14.8°C/W and junction-to-ambient resistance as low as 64.5°C/W on enhanced PCB layout, while the integrated body diode exhibits V_SD = 0.8–1.0V at 10A and t_RR = 19.6ns-suitable for freewheeling in hard-switched converters.

Key Specifications

Pinout & Package

Package: U-DFN2020-6/SWP (Type F), 2.0mm × 2.0mm × 0.6mm, with exposed drain pad for thermal and electrical connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DMTH4008LSDQ-7 and NTMFS4C023NT1G, the DMTH4008LFDFW uniquely combines ultra-compact U-DFN2020-6 packaging, +175°C qualification, and production-tested UIS robustness-making it the only option among the three for space- and temperature-critical automotive power switches.

Availability

DMTH4008LFDFW is available at Aetrix Electronics and suitable for automotive body control modules, industrial DC-DC converters, and LED backlight drivers requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for DMTH4008LFDFW 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-reliability power management, signal integrity, and protection solutions.

This MOSFET belongs to Diodes' Automotive-Grade PowerFET family, engineered specifically for robust operation in harsh environments including engine compartments, industrial motor drives, and outdoor power equipment.

FAQ

What is the maximum allowable gate-source voltage for DMTH4008LFDFW?

The absolute maximum gate-source voltage is ±20V per the datasheet's Maximum Ratings table. Exceeding this risks permanent gate oxide damage. For reliable operation, gate drive circuits should limit V_GS to ≤15V during transients and maintain tight control over overshoot using RC snubbers or active clamping.

Does DMTH4008LFDFW require a gate resistor, and if so, what value is recommended?

Yes-a gate resistor is essential to dampen ringing and control dV/dt. Based on its 1.82Ω intrinsic gate resistance and typical gate charge, a 5–10Ω series resistor is recommended for 10V gate drive in 300kHz DC-DC applications. Lower values increase switching speed but raise EMI risk; higher values reduce losses but increase switching time.

Can DMTH4008LFDFW be used in high-side configuration with bootstrap gate driving?

Yes, but only with appropriate level-shifting and bootstrap capacitor sizing. Its V_GS threshold (1.0–3.0V) and 10V-rated gate allow standard bootstrap drivers. However, due to its U-DFN2020-6 package lacking an isolated source pin, PCB layout must ensure low-impedance return paths and minimize parasitic inductance in the high-side loop.

How does the 0.6mm profile impact thermal performance compared to larger packages?

The 0.6mm height reduces vertical thermal resistance but increases reliance on PCB copper area for heat spreading. With proper 1-inch² copper pour, R_θJA drops to 64.5°C/W-comparable to SO-8. Without adequate copper, junction temperature rises sharply; therefore, the exposed drain pad must be soldered to ≥2oz copper with ≥4 thermal vias to achieve rated current.