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There
are 2 COMMON
types of IC SOCKETS in
use today:-
Available in various sizes from 8 to 64 pins. However their QUALITY can vary. By FAR the BEST is the TURNED PIN TYPE. Unfortunately they're the MOST EXPENSIVE. However they do give BETTER ELECTRICAL CONTACT with the IC leg, which is VERY IMPORTANT for RELIABILITY. When creating a DOUBLE-SIDED PCB tracks need to be connected to the DIP socket from BOTH sides of the board. The SOLDER SIDE connections are EASY, but the COMPONENT SIDE connections get OBSTRUCTED by the socket's PLASTIC BODY, making soldering difficult if not IMPOSSIBLE. A SPECIAL JIG described below is used to EXTRACT the pins from their FORMER. This makes the soldering of the COMPONENT SIDE pin MUCH easier. PLCC SOCKETS Available in various sizes from 20 to 84 pins. The SURFACE MOUNT type described here are purchased WITH a CENTRE SECTION as shown in the LEFT PHOTO below. The CENTRE SECTION needs to be REMOVED by gently pressing it out with a SCREWDRIVER. The result is shown in the RIGHT PHOTO below. The reason for REMOVING the PLCC socket's centre is so that VIA HOLE LINKS, discussed PREVIOUSLY, can be placed in the CENTRE of the PLCC socket, i.e. UNDERNEATH the PLCC device. The socket RAISES the PLCC device OFF the PCB ENOUGH to accommodate for the HEIGHT of the VIA LINKS but ONLY when the CENTRE SECTION of the PLCC socket is REMOVED. |
| If
PLATED-THRU-HOLE TECHNOLOGY
isn't available to you, but you need to produce DOUBLE
SIDED PCBs, then this technique described
is a solution.
The JIG described below is for EXTRACTING the DIL IC SOCKET PINS. The IC sockets used are a 16 WAY TURNED PIN type. These are used as they represent the CHEAPEST WAY of purchasing the socket pins. The JIG shown below can be constructed from a 4" VICE MOUNTED VERTICALLY. |
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| PLCC Socket Modification |
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