SMD package types describe the physical characteristics of devices that use surface mount technology (SMT) for attaching electronic components directly to the surfaces of printed circuit boards (PCB). In other words, an SMD is an electronic component that attaches to a PCB with SMT. This attachment method is faster than through hole technology (THT), which requires inserting component leads into drilled holes.
SMT supports the use of automated equipment and is a good choice for miniaturized components. Today, it is used widely with resistors, capacitors, transistors, diodes, and integrated circuits (ICs). Typically, SMD packages are named after their physical dimensions or have alphanumeric or lettered codes. The JEDEC Solid State Technology Association defines standards and some packages conform to EIA specifications.
The following sections describe common SMD package types and sizes.
SMD Resistors and SMD Capacitors
SMD resistors and SMD capacitors have rectangular packages with numbered designations that represent inch-based measurements.
SMD Package Type | Dimensions (mm) | Dimensions (inches) |
2920 | 7.4 x 5.1 | 0.29 x 0.20 |
2512 | 6.3 x 3.2 | 0.25 x 0.125 |
2010 | 5.0 x 2.5 | 0.20 x 0.10 |
1825 | 4.5 x 6.4 | 0.18 x 0.25 |
1812 | 4.6 x 3.0 | 0.18 x 0.125 |
1806 | 4.5 x 1.6 | 0.18 x 0.06 |
1210 | 3.2 x 2.5 | 0.125 x 0.10 |
1206 | 3.0 x 1.5 | 0.12 x 0.06 |
0805 | 2.0 x 1.3 | 0.08 x 0.05 |
0603 | 1.5 x 0.8 | 0.06 x 0.03 |
0402 | 1.0 x 0.5 | 0.04 x 0.02 |
0201 | 0.6 x 0.3 | 0.02 x 0.01 |
01005 | 0.4 x 0.2 | 0.016 x 0.008 |
SMD Transistors
There are three popular package types for SMD transistors. They use the small outline transistor (SOT) style.
- SOT-23 is used for small-signal transistors and measures 2.9 mm x 2.4 mm x 1.1 mm.
- SOT-323 is used where you need to fit in a smaller space and measures 2.1 mm x 2.1 mm x 0.9 mm.
- SOT-523 is used where you need the ultimate small size and measures 1.6 mm x 1.6 mm x 0.7 mm
Figure 1: SOT Package Types (Image Credit: Electrical Information)
SMD Integrated Circuits
There are five main package types for SMD integrated circuits (ICs).
- Small outline integrated circuit (SOIC)
- Small outline package (SOP)
- Quad flat pack (QFP)
- Plastic leaded chip carrier (PLCC)
- Ball grid array (BGA).
In addition, some SMD package types for ICs have multiple styles. SOP packages provide an example.
- Thin small outline package (TSOP)
- Shrink small outline package (SSOP)
- Thin shrink small outline package (TSSOP)
- Quarter-size small outline package (QSOP)
- Very small outline package (VSOP)
There are also different styles of QFP packages for surface mount devices.
- Low profile quad flat pack (LQFP)
- Plastic quad flat pack (PQFP)
- Ceramic quad flat pack (CQFP)
- Thin quad flat pack (TQFP)
These aren’t the only choices that are available, so it’s important to partner with an electronics manufacturer who can help you to make the right decisions for your application.
Get Help with SMD Package Types and Sizes
Z-AXIS of Phelps, New York (USA) is an electronic contract manufacturer that also offers electronic design services. We can help you with component selection and recommend specific SMD package type and sizes for your application. Contact us to get started.