IRF3205 — 55V 110A Ultra-Low Rds(on) (8.0mΩ) N-Channel Power MOSFET (TO-220)

Overview

The IRF3205 (IRF3205PBF) is an iconic high-current, low on-resistance N-channel power HEXFET MOSFET manufactured by Infineon Technologies (originally International Rectifier). Housed in a through-hole TO-220AB package, it is one of the most widely used power MOSFETs in the world for high-power switching applications.

Rated for a drain-to-source voltage of $55\text{V}$ , a massive continuous drain current up to $110\text{A}$ (silicon die limit; $75\text{A}$ package lead bond wire limit), and an ultra-low on-resistance of just $8.0\text{ m}\Omega$ ( $0.008\ \Omega$ ) at $V_{GS} = 10\text{V}$ , the IRF3205 delivers phenomenal thermal efficiency. Operating with a maximum junction temperature of $175^\circ\text{C}$ , it is the industry standard for 12V-to-220V/110V DC-AC power inverters, high-power H-bridge DC motor speed controllers, electric scooter/e-bike ESCs, solar battery charge controllers, and automotive high-side/low-side switches.

Quick reference


Transistor Type	High-Current N-Channel HEXFET Power MOSFET
Package	TO-220AB (3-pin through-hole) / D2PAK (SMD)
Drain-Source Voltage ( $V_{DSS}$ )	$55\text{ V}$ max
Continuous Drain Current ( $I_D$ )	$110\text{ A}$ ( $T_C = 25^\circ\text{C}$ , Silicon limit; $75\text{ A}$ Package Lead limit)
Pulsed Drain Current ( $I_{DM}$ )	$390\text{ A}$
On-Resistance ( $R_{DS(on)}$ at 10V)	$8.0\text{ m}\Omega$ ( $0.008\ \Omega$ ) max
Gate Threshold Voltage ( $V_{GS(th)}$ )	$2.0\text{ V}$ to $4.0\text{ V}$ (Requires $10\text{V} \dots 12\text{V}$ gate drive)
Gate-to-Source Voltage ( $V_{GS}$ )	$\pm 20\text{ V}$ max
Total Gate Charge ( $Q_g$ )	$97\text{ nC}$ typ ( $146\text{ nC}$ max)
Total Power Dissipation ( $P_D$ )	$200\text{ Watts}$ ( $T_C = 25^\circ\text{C}$ )
Operating Junction Temp	$-55^\circ\text{C}$ to $+175^\circ\text{C}$

Pinout (TO-220AB Package)

Looking at the front labeled face with leads pointing downward:

text

        ┌──────────────┐
        │  O  [Metal]  │ ── Tab is internally connected to Pin 2 (Drain)
        ├──────────────┤
        │   IRF3205    │
        └─┬────┬────┬──┘
          1    2    3
          G    D    S

Pin	Name	Type	Description
1	`GATE`	Gate Input	Gate control terminal (Drive with $10\text{V} \dots 15\text{V}$ for full $8\text{m}\Omega$ saturation)
2 (Tab)	`DRAIN`	Power Drain	Drain switching terminal (Internally connected to metal mounting tab)
3	`SOURCE`	Power Source	Source terminal (Connect to ground or negative return path)

Specifications

Parameter	Symbol	Min	Typ	Max	Unit	Conditions
Drain-Source Breakdown	$V_{(BR)DSS}$	55	—	—	V	$V_{GS} = 0\text{V}, I_D = 250\ \mu\text{A}$
Static Drain-Source $R_{DS(on)}$	$R_{DS(on)}$	—	6.5	8.0	mΩ	$V_{GS} = 10\text{V}, I_D = 62\text{A}$
Gate Threshold Voltage	$V_{GS(th)}$	2.0	—	4.0	V	$V_{DS} = V_{GS}, I_D = 250\ \mu\text{A}$
Drain-Source Leakage	$I_{DSS}$	—	—	25	µA	$V_{DS} = 55\text{V}, V_{GS} = 0\text{V}$
Gate-Body Leakage Current	$I_{GSS}$	—	—	$\pm 100$	nA	$V_{GS} = \pm 20\text{V}$
Diode Forward Voltage	$V_{SD}$	—	—	1.3	V	$I_S = 62\text{A}, V_{GS} = 0\text{V}$
Thermal Resistance	$R_{\theta JC}$	—	—	0.75	°C/W	Junction-to-Case

Typical Push-Pull Power Inverter / Motor Driver Stage

text

                      +12V to +24V High-Current Battery Rail
                                   │
                               [ + Load / Motor - ]
                                   │
                                   ├───[ Flyback Catch Diode (e.g. MBR20100) ]──┐
                                   │   (Anode to Drain, Cathode to Supply)     │
                             [Pin 2: DRAIN]                                    │
                                IRF3205                                        │
  Gate Driver (10V - 12V)    [Pin 1: GATE]                                     │
  (e.g. TC4420 / IR2104)           │                                           │
          │                        ├───[ 10kΩ Gate Pull-Down Resistor ]────────┤
          ├───[ 10Ω Gate Resistor ]┤                                           │
         GND                       │                                           │
                             [Pin 3: SOURCE]                                   │
                                   │                                           │
                                  GND ─────────────────────────────────────────┴─── Heavy System GND

Comparison: IRF3205 vs IRFZ44N vs IRLB8721

Parameter	IRF3205	IRFZ44N	IRLB8721
$V_{DSS}$ Rating	$55\text{ V}$	$55\text{ V}$	$30\text{ V}$
Max Current ( $I_D$ )	$110\text{ A}$	$49\text{ A}$	$62\text{ A}$
$R_{DS(on)}$ at 10V	$8.0\text{ m}\Omega$	$17.5\text{ m}\Omega$	$8.7\text{ m}\Omega$
Logic-Level 5V Drive	No ( $10\text{V}$ Required)	No ( $10\text{V}$ Required)	Yes ( $4.5\text{V}$ Logic Level)

Common mistakes

Attempting to drive directly from a 3.3V or 5V microcontroller pin: The IRF3205 is a standard-gate MOSFET, NOT a logic-level device. Driving its gate with $3.3\text{V}$ or $5\text{V}$ will leave the transistor operating in the linear resistive region, causing severe overheating and destructive thermal runaway under load. Use a dedicated gate driver IC (such as TC4420, IR2104, or a discrete BJT totem-pole driver) with a $10\text{V} \dots 12\text{V}$ supply. (For direct 5V logic drive, use the IRLZ44N or IRLB8721 instead).
Forgetting that the metal tab is live Drain: In TO-220 packages, the metal mounting tab is internally bonded to Pin 2 (Drain). When mounting multiple IRF3205s to a shared aluminum heatsink, isolate each tab using silicone thermal pads and plastic insulating bushings.

Notes

Package Rating: The silicon die handles 110A; standard TO-220 copper lead wires are rated for continuous currents up to 75A.

Interface	3-Terminal TO-220 (Gate, Drain, Source)
Package	TO-220AB (3-pin through-hole) / D2PAK / TO-262