TO-263 Component Package

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1. Overview


Transistor Outline 263 (JEDEC)


  • D2PAK (Double Decawatt package)

  • DDPAK (Double Decawatt package)

  • SMD-220 (named so because the TO-263 is the SMD equivalent of the TO-220).

  • TO-263 (Transistor Outline 263, JEDEC)

  • TO-263AB (TO-263-3S only)

  • TO-279 (TO-263 THIN only, by Texas Instruments)

Similar To



  • TO-263-X1X2 (where X1 is the lead count and X2 is the length of the centre pin).

  • TO-263 THIN (a thinner variant of the standard TO-263 package by Texas Instruments).



Pin Count

Depends on variant.

3, 5, 7, or 9 (this is X1). All packages also have a thermal pad.


Depends on variant.

  • TO-263-3, TO-263-3S: 2.54mm

  • TO-263-7, TO-263-7S: 1.7mm


Easy to solder by hand, as long as you have a decent powered soldering iron for the central thermal pad. Easy to solder with infrared and reflow techniques.

Thermal Resistance

Package LxWxH


  • All except TO-263 THIN: 4.57mm

  • TO-263 THIN: 2.00mm

Typical PCB Land Area

3D Models

See the variant information below.

Common Uses

  • High power MOSFETs

  • High power LDOs

  • High power SMPS (usually with integrated switching element)

2. The Standard Package (TO-263)

The TO-263 package can be considered the SMD version of the TO-220AB package. It is a 3, 5 or 7 leaded heavy-duty SMD package that allows for good heat-sinking due to a large pad on it’s underside. It is used frequently for high power MOSFETs, LDOs and SMPS. Comes with either a normal middle lead (X2 = nothing) or a short, cut-off middle lead (X2 = S).

d2pak to 263 component package 3d render
Figure 1. A 3D render of the TO-263 (D2PAK) component package.

3. TO-263-3

The TO-263-3 is the 3-pin variant of the TO-263.

The junction-to-ambient thermal resistance for the TO-263-3 component package on both standard JEDEC 2-layer and 4-layer boards is shown below:

d2pak to 263 component package thermal resistance 2 vs 4 layer comparison
Figure 2. Junction-to-ambient thermal resistance data of the TO-263 component package on both standard JEDEC 2-layer and 4-layer PCBs. Image from
  • \(T_{JA} = 18.0^{\circ}{\rm C}/W\) (1 square inch of copper surrounding pads, connected to ground)

  • \(T_{JA} = 33.6^{\circ}{\rm C}/W\) (copper filling package land-area)

  • \(T_{JA} = 36.7^{\circ}{\rm C}/W\) (pads only, no copper fill)

3D models:

4. TO-263-5

The TO-263-5 is the 5-pin variant of the TO-263.

Thermal resistance of the TO-263-5L THIN:

\(T_{JA} = 22.0^{\circ}{\rm C}/W\) (no air flow, on JEDEC 4-layer test board)

3D models:

5. TO-263-7

The TO-263-7 is the 7-pin variant of the TO-263.

3D models:

6. TO-263 THIN

TO-263 THIN is a variant of the TO-263 component package by Texas Instruments. It shares a similar PCB footprint, but is significantly smaller in height (i.e. thinner).

to 263 normal vs thin component package comparison.pdf
Figure 3. A comparison in dimensions of the standard TO-263 component package vs. the TO-263 THIN component package. Image from

It still has a similar exposed pad on it’s underside (making it footprint compatible with the standard TO-263 package).

The exact dimensions of the TO-263 THIN package are shown in Figure 4.

to 263 thin component package dimensions
Figure 4. The dimensions for the TO-263 THIN component package. Image built from elements taken from


Geoffrey Hunter

Dude making stuff.

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This work is licensed under a Creative Commons Attribution 4.0 International License .

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