Sockets 101- What is a socket?
Posted by James Forster on Fri, May 14, 2010 @ 12:47 PM
With the semiconductor industry improving, finding time to write this blog is certainly more difficult than I imagined. With that said this is the first of a series on understanding burn-in sockets, essentially an introduction to the technology of burn-in sockets or perhaps Sockets 101 or, in the current vernacular, A Sockets 411.
So what is a socket?
The Oxford English Dictionary defines socket as...
- a hollow in which something fits or revolves.
- an electrical device receiving a plug or light bulb to make a connection.
Wikipedia has more than 10 different types of socket -
Certainly all the motorheads would think of a socket wrench where the sockets are the business end to help remove nuts and bolts.
Medical professionals would think of a the variety of sockets and joints in the body such as eye, hip, knee, elbow, foot or shoulder where a socket allows a variety of human movements.
If we think about our homes and our electrical applicances such as toasters, coffee makers etc we have all used electrical wall sockets and are familiar with the plugs which provide a temporary connection to the houses electrical supply .
The images here show a variety of different sockets and plugs from around the world.
Unfortunately there is no international standard so travelers can be frustrated as they try to use their computers, hair dryers or other electrical appliances. An international "adapter socket" has even been created which allows these devices to be "plugged" into the sockets in the foreign country, even if the voltage and current may not be compatible
We are also familiar with the different "sockets" on a computer which provide a place to connect a variety of different "peripherals" such as printers, monitors etc so that they can communicate and talk to the computer. USB is now the dominant "plug" but even within that there are different formats sizes.
In all of these cases the socket holds the plug and provides an electrical connection to allow the passage of an electrical power or a signal. This is very different than soldering which is a method to permanently attach the two.
When testing a semiconductor packages it is necessary to hold the device and provide a temporary electrical connection. So for a burn-in socket my definition would be:-
A burn-in socket is a device which provides a temporary mechanical and electrical interconnection to allow the testing of a semiconductor package.
The key words in this definition are temporary and electrical interconnection.
The socket must hold the package or device under test (DUT) while it is being tested. Once the test is complete the package must be undamaged and easily removed so that another device can be inserted.
The next blog will discuss how the socket is connected to the test board.
The picture below shows some of our burn-in sockets
If you have any comments or thoughts please post a reply or send me a note at james.forster@wellscti.com