PCB DIP: Difference between revisions
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This is a way to make a PCB with DIP legs. | This is a way to make a PCB with DIP legs. | ||
The legs are thin & flat like chip legs, and so do not exceed the specs of DIP sockets. Normal square pin headers are really not good for DIP sockets. The pins are too | The legs are thin & flat like chip legs, and so do not exceed the specs of DIP sockets. Normal square pin headers are really not good for DIP sockets. The pins are too thick and stretch out the socket contacts so that the socket no longer grips real DIP chip legs as firmly. Machined round pins are thinner and better, but even they are still almost twice as thick as chip legs. There are some special "micro pins" from Mill-Max and at least one other manufacturer, but even those are technically thicker than the specs that socket data sheets claim to support officially. | ||
The completed PCB is very low profile and fits in many places where a larger board with pin header insulators and shoulders do not fit. | The completed PCB is very low profile and fits in many places where a larger board with pin header insulators and shoulders do not fit. | ||
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The SIL leadframe that provides the pins: [https://www.digikey.com/en/products/detail/te-connectivity-amp-connectors/1544210-2/4731536 TE 1544210] | The SIL leadframe that provides the pins: [https://www.digikey.com/en/products/detail/te-connectivity-amp-connectors/1544210-2/4731536 TE 1544210] | ||
The size of the drill holes is very close to to the size of the pins, so that the pins barely fit, which helps keep the pins aligned perpendicular to the board. | The size of the drill holes is very close to to the size of the pins, so that the pins barely fit, which helps keep the pins aligned perpendicular to the board before & during soldering. | ||
Optional step not shown in the pics: Put kapton tape on the pins on the bottom side, covering both the inner and outer sides of the pins, and right up to the PCB to cover the entire exposed leg, to keep solder from wicking down the length of the leg and making the legs thick and lumpy. The tin surface really actively wicks the solder even if you're very careful and only provide solder from the top side of the pcb. | |||
Latest revision as of 18:05, 19 November 2020
This is a way to make a PCB with DIP legs.
The legs are thin & flat like chip legs, and so do not exceed the specs of DIP sockets. Normal square pin headers are really not good for DIP sockets. The pins are too thick and stretch out the socket contacts so that the socket no longer grips real DIP chip legs as firmly. Machined round pins are thinner and better, but even they are still almost twice as thick as chip legs. There are some special "micro pins" from Mill-Max and at least one other manufacturer, but even those are technically thicker than the specs that socket data sheets claim to support officially.
The completed PCB is very low profile and fits in many places where a larger board with pin header insulators and shoulders do not fit.
KiCAD source for some boards that use this method, which can be used as a template for new boards: http://github.com/bkw777/aDIPters
The SIL leadframe that provides the pins: TE 1544210
The size of the drill holes is very close to to the size of the pins, so that the pins barely fit, which helps keep the pins aligned perpendicular to the board before & during soldering.
Optional step not shown in the pics: Put kapton tape on the pins on the bottom side, covering both the inner and outer sides of the pins, and right up to the PCB to cover the entire exposed leg, to keep solder from wicking down the length of the leg and making the legs thick and lumpy. The tin surface really actively wicks the solder even if you're very careful and only provide solder from the top side of the pcb.