SO design

from Wikipedia, the free encyclopedia
SO16 design

SO stands for Small Outline and describes a housing shape for integrated circuits (IC). SO-ICs are 30–50% smaller than corresponding DIL -ICs. It is a surface-mounted device (SMD) design, ie a "surface-mounted" one. The base is rectangular and there are two rows of pins on the longer sides. The pins are of the gull wing type , so they protrude to the side.

Despite the similar name, no SO-type ICs are used on memory modules such as SO-DIMM. The more compact TSSOP , SSOP and, more recently, BGA designs are used there.

variants

The 8, 14 and 16-pin versions of the SO design have been standardized by JEDEC . There this design is called MS-012, which also describes so-called "Thermal Enhanced Versions" with "Exposed Pad" (solderable cooling surface on the underside).

The full name for this design is at JEDEC : "PLASTIC DUAL SMALL OUTLINE GULL WING, 1.27 MM PITCH PACKAGE".

The design designation is usually extended by a number that indicates the number of pins (eg: "SO8").

This standard was extended by individual manufacturers without authorization. The variety then ranges from "SO4" to "SO64".

In addition to the JEDEC variant with a housing width of 3.9 mm, also called "narrow", there is an EIAJ variant with a housing width of 5.4 mm, also called "wide" the printed circuit boards interchangeable.

Housing dimensions

The picture shows an SO-IC with dimensions, the values ​​can be taken from the table. All information in mm.

A SOIC, with package dimensions

C Distance between the component body and PCB
H total height
T pin height
L component length
L W pin width
L L pin length
P pitch
W B housing width
W L component overall width
O overhang
size in mm
Surname Pins W B W L H C. L. P L L T L W O
SO8 8th 3.9 ± 0.1 6.2 1.75 0.25 4.9 ± 0.1 1.27 0.41 0.19 0.51 0.33
SO14 14th 3.9 ± 0.1 5.8-6.2 1.72 0.10-0.25 8.65 ± 0.1 1.27 1.05 0.19-0.25 0.39-0.46 0.3-0.7
SO16 16 3.9 ± 0.1 5.8-6.2 1.72 0.10-0.25 9.9 ± 0.1 1.27 1.05 0.19-0.25 0.39-0.46 0.3-0.7
SO16W 16 7.5 10.00-10.65 2.65 0.10-0.30 10.1-10.5 1.27 1.4 0.23-0.32 0.38-0.40 0.4-0.9

SOP

A flash memory chip in the SOP housing

SOIC was followed by a family of smaller designs, Small Outline Package ( SOP ), with a pin spacing of approx. 0.65 mm:

  • Plastic Small-Outline Package ( PSOP )
  • Thin Small Outline Package ( TSOP )
  • Shrink Small Outline Package ( SSOP )
  • Thin-Shrink Small Outline Package ( TSSOP )
  • Quarter-Size Small Outline Package ( QSOP )

The ICs on DRAM - memory modules were usually TSOP until this design due to the so-called ball grid array has been replaced (BGA).

Individual evidence

  1. ↑ Packaging Information for Type: SOIC. In: Semiconductor Packaging Information by Type / SOIC. Texas Instruments, accessed on April 7, 2013 (English, SOIC overview according to JEDEC standard ).

Web links

Commons : SOIC integrated circuit packages  - collection of images, videos and audio files