The effect of the price of copper on the thickness of TO220 packages

I noticed, and was appalled, when my recent order of Fairchild TO-220s = were *way* under spec.

Evidently, they have "single" and "dual gauge" (note F).

LT gives 1.143-1.397mm, a rather imprecise range.

After a quick browse, Fairchild seems to be the only company cheating = this JEDEC spec.

Tim

--=20 Deep Friar: a very philosophical monk. Website:

It needs to conform to the thermal spec of that part to be able to be legally called that part. i.e. the original data sheet that the oem chi maker claims to be compliant with in order to call it that part. Otherwise, it is a fake or a counterfeit, no ifs ands or buts. OR they have to put a DIFFERENT moniker on it and tout it as a "suitable replacement" or such.

A claim of being fully compliant with the spec that part originally had requires true full compliance with said specs.

Cutting away sinking mass leads to obvious alterations in those specs. There is no way around it. They are cheap fakes.

On a sunny day (Fri, 23 Jul 2010 10:41:59 -0700 (PDT)) it happened Nunya wrote in :

Yes, I suppose the heat conductivity changes, also the mounting becomes less reliable in my view. Here is a picture that compares this thin 7805 with a normal IRF TO220 MOSFET, the 7805 is on the right: ftp://panteltje.com/pub/thin_7805_compare_img_2090.jpg

This is the markings it shows: ftp://panteltje.com/pub/thin_7805_img_2092.jpg

ON Semi spec says min is 0.508 mm ......

*way* under spec.

JEDEC spec.

Nope ST is doing the single/dual gauge as well see page 40-41 of the

7800 series regulator data sheet.

ere *way* under spec.

is JEDEC spec.

I think that is funny... "In spite of some difference in tolerances, the packages are compatible."

Note how that is all under the header "Mechanical data". Is not thermal performance a mechanical engineering function? It seems like a vague claim when we all know for sure that the sinking mass difference will present a performance shift at the upper end of the operating window.

It *might* be proper if they had classed it as mil spec and commercial or something like that and actually went through the trouble of noting the difference.

Going "COTS" was a mistake, at least at the discreet device level. We should still have hi-rel US fabs and we do not, and even the overseas hi-rel stuff is evaporating. All folks are willing to pay for performance, but makers are getting lame as they shy away from actual culpability for anything they make.

At the consumer level, Sony is a fine example of just how disconnected a company can get with their customers. If you are on their bandwagon, feeding them cash from various directions (seems everyone's disease these days), then you are ignored, and they have a hardware warranty program that is lame beyond pale. My 'was under warranty' PS3 would have been serviced for me, under warranty, for a mere $145, and they would not have serviced MY unit, but merely send me back some lame refurb unit. That is truly lame behavior. Many folks spend a lot of hours working on their personal devices, and they would not want some lame, who knows how many hours it has on it refurb back instead of them actually repairing your unit. It should be illegal. Not to mention the fact that the defect 'occurred' after they changed the spindle speed on the BluRay drive via firmware, and forgot that some of the units had different drive motors in them that could not handle the higher rate. Their screw up, yet they want money from us to fix it, instead of releasing a proper firmware update that returned the drive to an operable state. Admitting the mistake is not on their list of things they want to do, since so many jumped on the sucker's pay-us-and-we'll-fix-it-bandwagon. It would cost them a lot.

On a sunny day (Fri, 23 Jul 2010 15:20:13 -0400) it happened Hammy wrote in :

*way* under spec.

JEDEC spec.

I did not know that. In my view .51 is too thin, as then when bolted against a heatsink, say on a PCB, the slightest pressure on the leads will push it away from the heatsink

heatsink | ||| package |--| screw ||| | \\ -> force away from heatsink | \ ===0============ solder VIA Bit exagerated view.

*way* under spec.

JEDEC spec.

heatsink

I didn't know that either. I agree it is too thin structure wise not to mention what it does thermally.

I went through some of my TO220's and compared them, the ones I checked are the dual gauge.

Its safe to assume they are all doing it.

The thing is how do you know you are ordering the dual or single gauge?

Looking at the package spec sheet that Tim linked too I see no mention in the revisions about adding single/dual gauge. The document was first released in 1991 WTF*. Have they been doing this since 1991?

*See the revision list top right of the Fairchild doc.

the heatsink

You are supposed to attach planar surfaces (heat sink mating face) first, then perform the solder operations on the leads, and there should be no stress on those leads before (or after) said solder process.

Then, the leads and solder joints actually serve to bolster the planar heat sink interface placement.

Most folks these days use a pressure foot placed upon the package itself, directly above the device die location, to apply pressure where it achieves the greatest work product for the application., i.e. heat sinking of the heat source.

Never solder leads, then force the part over to the sink, and never attach to the sink and then apply force opposed to that by way of failing to remove any back pressure the leads may be placing on the part by less than optimal lead forming practices.

This problem amplifies itself when these devices get ganged onto a common sink. It is also one of the causes of a specific form of solder creep circuit failure.

We have 7912's that are thinner than usual. But havent seen 7805's that thin yet.

Cheers

On a sunny day (Fri, 23 Jul 2010 12:41:55 -0700 (PDT)) it happened Nunya wrote in :

Sony is a very strange company. My experiences with Sony are ... many... and differ. Once they tried to buy me away from the company I worked :-) I declined, good decision in retrospect.

They are technologically very good, or can be, still make the strangest mistakes. They cut corners in the strangest places. The first time that really showed was when they sold trinitron PAL TVs, and, to not have to pay the PAL license fees, they used a modified NTSC decoder. So the sets had a color hue control, like a NTSC set at that time, something PAL had made obsolete. Many were sold. In fact trinitron was an inferior color CRT too, but it was brighter, so they pushed that, and lots of people bought it. I had many Sony products, and most just stopped working rather soon. I do have a Sony alarm clock radio that still runs fine... When they announced the PS3 I wanted to buy one because it was supposed to have

2 HDMI slots, and run Linux. When it finally appeared on the marked it had only one HDMI slot and the Linux had no access to the graphics, so I did not buy that. Then somebody hacked the supervisor in it some time ago, and they came with a firmware upgrade that disabled Linus altogether,. Nice for people who just bought it for that. So, they *can* make great stuff, professional video stuff too, but they screw up in a bad way indeed on some details sometimes. Before you buy something from them, read some customer experiences for that product, plenty on the internet these days, And that goes for any manufacturer of course.

mistakes.

And, once you notice the two horizontal lines on a Trinitron monitor, the screen is never the same again, distracting.

Grant.

That looks like an ON Semi MC7805 part. They changed to single gauge in 2006. Here's their initial 2005 notice,

and their final 2006 notice and publication, Effective Date: 2006-07-25

As others have pointed out, many if not most companies are offering "single-gauge" 0.020-inch TO-220 tabs now. Hopefully this change is reflected in the price.

Here's a five-year chart of copper prices,

--
 Thanks,
    - Win

On a sunny day (26 Jul 2010 02:48:46 -0700) it happened Winfield Hill wrote in :

Thank you, amazing info. Never too old to learn :-) Copper is way up there today, .25 mm TO220 coming next? I have already used the thin tabs to my advantage by bending it, to save space:

mistakes.

2 HDMI slots, and run Linux.

had no access to the graphics,

firmware

product, plenty on the internet these days,

And never forget to keep your salt lick handy when reading internet reviews.