I'm pretty sure that military grade parts have paperwork and processes to
cover that case.  I expect it costs a lot.

I think the same sort of service is available to high volume customers at a
less than military price.

Or, as Javier said:

So maybe it doesn't take a high volume, you just have to get plugged into the
right paperwork flow and then read all the fine print to see if the change is
interesting.

--
These are my opinions, not necessarily my employer's.  I hate spam.

El 14/08/2010 19:17, Hal Murray escribió:

Yes. I'm not a high volume customer, only mid-to-low :) But I receive
the PCNs even for components that I've only purchased one 50pcs bar for
a special project. But I'm not sure if all manufacturers are the same.
This example from NXP is very very detailed, in other cases there is
only a note that production has changed from one factory to another.

Regards,

Javier

--

Javier Herrero                            EMAIL: jherrero@hvsistemas.com
HV Sistemas S.L.                          PHONE:        +34 949 336 806
Los Charcones, 17                        FAX:          +34 949 336 792
19170 El Casar - Guadalajara - Spain      WEB: http://www.hvsistemas.com

Hi

Not so much.

Mil grade just makes sure they qualify a change.

At the time we had the issues the volume on the transistors was quite high. The cost os screening was still prohibitive. They write the specs with very few limits for a reason....

Bob

On Aug 14, 2010, at 1:17 PM, Hal Murray hmurray@megapathdsl.net wrote:

Hi

I seem to get weekly notices about a resin changing or a new date code format. Silicon changes don't seem to be on the same "system". That's still better than it was 30 years back.

Bob

On Aug 14, 2010, at 1:38 PM, Javier Herrero jherrero@hvsistemas.es wrote:

I sometimes get some PCNs about process changes on silicon (new process
or new masks). I suppose that depends on manufacturers :)

Regards,

Javier

El 14/08/2010 19:49, Bob Camp escribió:

--

Javier Herrero                            EMAIL: jherrero@hvsistemas.com
HV Sistemas S.L.                          PHONE:        +34 949 336 806
Los Charcones, 17                        FAX:          +34 949 336 792
19170 El Casar - Guadalajara - Spain      WEB: http://www.hvsistemas.com

Mil specs cover a number of things that are not always in the commercial specs, but not always, and mil spec parts are going the way of the dodo. Nobody wants to make them, except the local garage shop which does not mind selling you $0.02 parts for $60 (quite common) and the worst is that these parts are often made in very small runs from the old masks, or they are custom packaged dies bought from commercial sources and screened to meet the requirements and end up having very poor reliability because the small runs do not allow the quality of commercial parts made in the gazillion.

Quite a paradox!!!

In my 30 years experience designing military and space hardware, I now believe the commercial grade plastic parts you get from Digikey are quite a bit better than the expensive mil spec ones in the hermetic packages, even when rated 0-70C and when used in a humid environment.

Of course, if you have to have hermetic parts to satisfy an explicit customer requirement, that's another story, even though I have been fairly successful at obtaining waivers from customers in that regard.

Didier

Sent from my BlackBerry Wireless thingy while I do other things...

-----Original Message-----
From: Hal Murray hmurray@megapathdsl.net
Sender: time-nuts-bounces@febo.com
Date: Sat, 14 Aug 2010 10:17:32
To: Discussion of precise time and frequency measurementtime-nuts@febo.com
Reply-To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Subject: Re: [time-nuts] Simulation

I'm pretty sure that military grade parts have paperwork and processes to
cover that case.  I expect it costs a lot.

I think the same sort of service is available to high volume customers at a
less than military price.

Or, as Javier said:

So maybe it doesn't take a high volume, you just have to get plugged into the
right paperwork flow and then read all the fine print to see if the change is
interesting.

--
These are my opinions, not necessarily my employer's.  I hate spam.

time-nuts mailing list -- time-nuts@febo.com
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Hal Murray wrote:

just so..

In the space business, we call it "traceability to sand"... you haven't
lived til someone has a failed 2n2222, somwhere on some piece of
critical hardware, and they issue a GIDEP alert, and then the mission
assurance folks call you up and ask, "you don't by any chance have
2N2222's in your flight hardware do you?".. then there's the whole
manufacturer and date code hunt.. Looking through the build
documentation to find out. (or worse yet, if you had decided for some
reason to use the prototype, which you didn't keep such good records on,
but which you have photos of, and trying to read the date codes off the
assembled item with a magnifying glass)

On Apollo they had file cabinets full of drawers for IBM punch cards,
except each had a microfilm insert.

They could trace a single #6-32 screw back to the mine the iron ore came
from.

-John

=============

Once I had a batch of JANTX 2N2222A (with all the paperwork) that were PNPs. They actually were marked JANTX 2N2222A. This was for a mil job in the 80's. We did not fool around with the mil specs back then.

I was a young engineer then and not all that involved in the process, so I was kept somewhat out of the process that followed. I wish I has seen QA and purchasing explain that one :)

Didier

Sent from my BlackBerry Wireless thingy while I do other things...

-----Original Message-----
From: jimlux jimlux@earthlink.net
Sender: time-nuts-bounces@febo.com
Date: Sat, 14 Aug 2010 14:42:39
To: Discussion of precise time and frequency measurementtime-nuts@febo.com
Reply-To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Subject: Re: [time-nuts] Simulation

Hal Murray wrote:

just so..

In the space business, we call it "traceability to sand"... you haven't
lived til someone has a failed 2n2222, somwhere on some piece of
critical hardware, and they issue a GIDEP alert, and then the mission
assurance folks call you up and ask, "you don't by any chance have
2N2222's in your flight hardware do you?".. then there's the whole
manufacturer and date code hunt.. Looking through the build
documentation to find out. (or worse yet, if you had decided for some
reason to use the prototype, which you didn't keep such good records on,
but which you have photos of, and trying to read the date codes off the
assembled item with a magnifying glass)

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