View Full Version : Inserting ICs

February 12th, 2010, 05:30 PM
This article covers the insertion of socketed ICs. For the fitting of soldered-in parts, see soldering ICs.
Before inserting a DIP part into its socket, ensure all pins are straight and evenly spaced. If pins are bent ?sideways? such that the pins are not evenly spaced, they can be gently bent back using a small pair of pliers. If the pins are bent ?inwards? or ?outwards? such that they are no longer aligned with each other, this is easily fixed by pushing the row of pins evenly against a hard surface, like a workbench, with a slight rolling motion. This trick can also be used to adjust the spacing between the two rows of pins to ensure a good fit in the socket, and must be done with new ICs, which come from the factory with the pins bent slightly outward. If this spacing is not correct, the spring action of the pins can contribute to the chip working itself loose over time.
There are special tools designed to facilitate the insertion of DIP chips, but the task can still be accomplished without one. With the pins straight and evenly spaced, position the IC on top of its socket. Check for proper location of all pins so that none will be bent when the chip is pushed in. Using firm (probably firmer that you?d expect, if there are a lot of pins!) even pressure, push the IC fully home into its socket. Check again that no pins are bent outside the socket or under the body of the chip (if so remove it and reinsert).
Inserting an IC into a ZIF socket is simplicity itself. Ensure the locking mechanism is in the open position, to accept the IC?s pins. Observing correct orientation, (usually indicated by a slightly different pattern of pins in one or more corners or a mark for pin #1 on a DIP), drop the IC into place. If the IC doesn't drop easily into place, there is something wrong. DO NOT FORCE IT! Lift the chip and look for bent pins, etc, and ensure that the socket is open and not closed. After the chip is properly seated, close the socket. Some ZIF sockets utilize a lever to tighten on the pins, others use a screw with an eccentric head. Push the lever down into the locked position or turn the screw to clamp the IC in place.
Although there are special tools designed for this purpose, PLCC chips can also be simply pushed into their sockets. Use the beveled corner to orient the part correctly in the socket and, ensuring all pins are correctly aligned, apply even pressure to push the chip home.
See Also
Removing ICs
Reseating ICs