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Small Outline Integrated Circuit-How To Choose


With the popularity of integrated circuits, the need of them in a circuit board grew multiply.During the early days all integrated circuit were packed only with single and dual inline packages. Their massive size restricted the ability to shirk the footprint of the electronics appliances.To make the integrated circuit more compact and smooth the small outline integrated circuit was introduced.


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1.Conversion and technology

2.SOIC standards and types

3.Advantages of Small outline integrated circuit


1.Conversion and technology

The small outline integrated circuit(SOIC) usually takes only 30- 45 % of the total space required by their dual in line package counterparts. Small outline integrated circuits only have 30 % thickness of the DIP package. Small outline integrated circuits have identical pin out.And the performance other than the surface area.


Some of them are made to consume less power than the equivalent DIP package in some cases.  For low power application of that particular package.


Part numbers on the packages are sometimes shortened to fit in the reduced area. SOIC was widely used since late 70’s.


Small outline integrate circuit has package information stating with the prefix SO.


The number following the prefix is usually the pin count of that specific integrated circuit.


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2.SOIC standards and types

Integrated circuit packaging regulated and standardized to optimize the instalment.And to reduce the machining cost during the proception of printed circuit boards and integrated circuit systems themselves.


In the case of small outline integrated circuit, the package size and pin sizes are made with reference.


Which from the Electronics Industries Association of Japan and JEDEC solid state technology association standards.


Although the EIAJ model had a body diameter of approximately 5.3 mm the diameter is completely depend on the device.


Since there are many variants with different structural measurements. But, in most cases small outline integrated circuits have a lead spacing of 1.25 mm.


SOIC has few variants such as small outline J-leaded package(SOJ), shrink small outline package(SSOP), mini small outline package(MSOP) and thin small outline integrated circuit package(TSOP).


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Each of the variants have different body size and thickness. But, all of them will have same pin mapping and circuit configurations.


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3.Advantages of Small outline integrated circuit

The major advantage of the small outline integrated circuit is the footprint reduction. Reduction in space consumption resulted in smaller printed boards sizes. SOIC also reduced the fabrication cost of the integrated circuits by reducing the materials used in the packaging.


Smaller size components are easy to assembly by a machine than a larger size package. Since small outline integrated circuits are practically SMD multi-layer boards are only possible through these types of packaging.


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Hi, I am Hommer, the founder of WellPCB. So far we have more than 4,000 customers worldwide. Any questions you can feel free to contact me. Thanks in advance.