Whoops - sorry for the confusion of using a term that already relates to a specific technology. I haven't had the opportunity to work with the traditional wire wrapping, and I guess that now shows!

As Dean suggests, my inquiry is about SMT parts where the wire coming from in the part is wrapped around some portion of the molded body and becomes the solderable termination. These are typical of coils/transformers where a coil of wire is a major part of the internal part construction. The resulting termination may be a single wrap of wire, or there may be several wraps. I've also seem some cases where the wire coming from the coil is soldered to a larger wrap of wire or metal strip at the termination.

Ben

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D
Sent: Monday, December 3, 2018 5:09 PM
To: [log in to unmask]
Subject: EXTERNAL: Re: [TN] Wire wrapped terminations

Hi, Bob
I also am very familiar with the definition of "Wire-wrap" technology that pops up in your mind when you hear those words. I worked on wirewrap backplanes for years on the old Mk2/Mod 1/Mk46 Torpedoes that used wirewrap technology for point-to-point connection on the backplanes.
But what Ben is looking for is information describing acceptable solder joint criteria on the portion of the termination that gets soldered onto the board pads, ie, on small magnetics components, where the wire wrap ends.

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Bob Landman
Sent: Monday, December 03, 2018 4:01 PM
To: [log in to unmask]
Subject: Re: [TN] Wire wrapped terminations

Ben,

That's a term I haven't heard in a long time!

Wire wrapped terminations were developed by AT&T many many years ago.  Gardner Denver made the wire wrap tool I have.  Computer backplanes (e.g. Digital Equipment Co).  The wire (30ga is what I typically used) was silver plated.

See https://en.wikipedia.org/wiki/Wire_wrap 

When I worked at Comsat Laboratories in Clarksville, MD I built very high frequency (500MHz?) circuits for satellite communications with MECL ICs (using twisted pairs of wires with 50 ohm terminations were developed by Motorola for Comsat.  The Tek oscilloscope I used for troubleshooting had a sampling plug-in as standard oscilloscopes at that time (1970s)did not have the bandwidth.

See https://en.wikipedia.org/wiki/Emitter-coupled_logic

Beginning in the early 1960s, ECL circuits were implemented on monolithic integrated circuits and consisted of a differential-amplifier input stage to perform logic and followed by an emitter-follower stage to drive outputs and shift the output voltages so they will be compatible with the inputs. The emitter-follower output stages could also be used to perform wired-or logic.

Motorola introduced their first digital monolithic integrated circuit line, MECL I, in 1962.[18] Motorola developed several improved series, with MECL II in 1966, MECL III in 1968 with 1-nanosecond gate propagation time and 300 MHz flip-flop toggle rates, and the 10,000 series (with lower power consumption and controlled edge speeds) in 1971.[19] The MECL 10H family was introduced in 1981.[20] Fairchild introduced the F100K family.[when?]

Here's pictures of some of the Gardner-Denver wire wrap tools

https://www.ebay.com/p/Gardner-denver-Model-14XA2-Electric-Wire-Wrap-Tool/1971302306

I would guess AT&T Bell Labs would have the documentation on testing as I think that's where the technology was developed.

Bob Landman
President
Life Senior Member, IEEE
H&L Instruments, LLC
PO Box 580
34 Post Road
North Hampton, NH 03862
tel (603) 964-1818
www.hlinstruments.com

 

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Gumpert, Ben
Sent: Monday, December 03, 2018 4:44 PM
To: [log in to unmask]
Subject: [TN] Wire wrapped terminations

TechNetters,

Is anyone familiar with what I'll call 'wire wrapped terminations'?

Such as:
https://www.mouser.com/ProductDetail/Coiltronics-Eaton/CTX300-4-R?qs=yzwxPInThYQ4vFyw6jLRIQ%3D%3D
http://www.vishay.com/docs/34069/lpt4545.pdf
https://products.pulseelex.com/product-details/p0926nl/163/

A request came up at the last J-STD-001 committee meeting for solder joint criteria on these types of terminations, but without any suggestions.
I can't find anything from the vendors for a recommendation. Does anyone know of any testing done with these parts, or know of some recommended solder joint criteria?

Ben