Author Topic: DIP source -- the plastic/ceramic package itself.  (Read 1999 times)

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Offline JMThomasTopic starter

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DIP source -- the plastic/ceramic package itself.
« on: February 04, 2018, 11:36:21 am »
I'd like to mount something on a DIP package.

Long time ago (40 years), I saw some chips packaged in DIPs which started with the bottom half of a DIP, legs on, top hollowed out to receive the semi-conductor.  The die was mounted, whiskers soldered to pads and legs, then a top set in place and welded on.

I'm sure this has been totally automated, but I wonder if the current process still starts with two halves, and if so, is there a source for them?

My ideal would be a DIP with copper on top connected to the legs which could then be trimmed/etched into mounting pads.

An alternative would be the two halves, where I could cover the top half with copper foil (tape from stained glass?) and attach the bottom half to make good contact with the legs.

Any ideas where to look?
 

Offline Wolfram

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Re: DIP source -- the plastic/ceramic package itself.
« Reply #1 on: February 04, 2018, 11:54:52 am »
Kyocera seems to have a range of relevant products: https://global.kyocera.com/prdct/semicon/semi/std_pkg/ . Depending on what you want to use them for, it might be viable to make something using a printed circuit board and a male DIP header like this one: https://www.digikey.com/product-detail/en/cnc-tech/220-1-14-003/1175-1520-5-ND/3441515
 

Offline ConKbot

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Re: DIP source -- the plastic/ceramic package itself.
« Reply #2 on: February 04, 2018, 06:25:16 pm »
http://www.topline.tv/DIP.html. They sell ceramic DIP packages, open so you can add what you like inside and solder on the lid, or closed for use as dummies. Not sure if the exposed pads are solderable, or wire bond only. Some metalizations can be soldered, some dissolve into solder and de-wet the ceramic quickly.  No online store, so expect the prices to be more than you would expect.
 

Offline mariush

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Re: DIP source -- the plastic/ceramic package itself.
« Reply #3 on: February 04, 2018, 06:28:11 pm »
Could you maybe 3D print yourself such cases, and use right angle 0.1" spaced pins for the legs?
 

Offline coppice

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Re: DIP source -- the plastic/ceramic package itself.
« Reply #4 on: February 04, 2018, 06:59:06 pm »
If you are trying to mount a die, several people supply open packages, like the Kyocera ones Wolfram referenced above. They are priced for prototyping, though, so they can be seriously pricey. Most IC prototypes are mounted in scoop and goop packages these days, so the market for those Kyocera packages must be tiny.

If you are trying to mount anything other than a die, a typical lead frame is not going to give you enough space. A small PCB, with pins underneath in a DIP layout, is likely to be a better solution, unless you are looking at serious volumes.
 

Online SeanB

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Re: DIP source -- the plastic/ceramic package itself.
« Reply #5 on: February 04, 2018, 07:54:16 pm »
Easiest would be a small PCB with the edges drilled with the appropriate pin layout on 0.1in centres with the traces as needed. The package you are thinking of is the standard windowed ceramic package used for Eproms, with either a glass frit seal or a  ement adhesive holding the top on. Plastic packages start off as a punched metal tape with the IC mounted on a paddle in it, with the leads wire bonded to the chip and the tabs, then the whole lot is placed in a die filled with a thermoset epoxy powder and compressed and heated till the cure time is exceeded and the chip is fixed in the package for good.

What you want is basically the common Arduino nano package, complete with the pin headers to mount it to another board. If it is to mount a chip itself then as said by Coppice the chip bonded to the FR4 and wire bonded in and blobbed in is the right thing to use.

The Kyocera package is used to convert SM devices to DIP, a very common requirement to use SM parts in military and space based applications, where the part is no longer available in DIP but redesigning the board in a SM version would either be difficult as they no longer have the original designs in readable form, or the board would need a very long drawn out and expensive recertification process, while the certification of the chip alone is a lot easier as the die and pinouts are already certified, and it is a drop in part. Price is in the dozens of dollars per unit in bulk, and it is a custom design in almost every time, basically a custom hybrid part in DIP.
 

Offline Cloud

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Re: DIP source -- the plastic/ceramic package itself.
« Reply #6 on: February 04, 2018, 08:14:06 pm »
If you need adapter from die to DIP the easiest way is to create bonding adapter pcb. If you need it for more than prototyping you can just cover it with some epoxy
 

Offline TimFox

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Offline JMThomasTopic starter

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Re: DIP source -- the plastic/ceramic package itself.
« Reply #8 on: February 05, 2018, 10:15:33 pm »
Thank you very much for all the material!

My wrong turn seems to be getting hung up on a DIP socket, and looking for something with thinnish rectangular legs meant to plug into said.

You showed me that changing from a DIP to a machined pin socket allows a host of different carriers. 

I'm grateful for your experience and wisdom. 
 

Offline JMThomasTopic starter

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Re: DIP source -- the plastic/ceramic package itself.
« Reply #9 on: February 06, 2018, 02:20:13 am »
FWIW, I stumbled across what I had been envisioning: https://www.jameco.com/z/3861501-Fundamentalz-SOIC8-SMD-Adaptor_2216913.html (US$13+shipping). 
 


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