Prev: Relay Question
Next: Baxandall class D oscillator, can it produce a triangle likewaveform?
From: Jan Panteltje on 23 Jul 2010 12:19
My old 7805 stabilisrs have 1.3 mm thick copper.
The new ones I bought today are .5 mm.
The new ones you can just bent with plyers, even break the tab off.

Wonder when we go to .25 :-)
From: Tim Williams on 23 Jul 2010 13:22
I noticed, and was appalled, when my recent order of Fairchild TO-220s were *way* under spec.

http://www.fairchildsemi.com/products/discrete/packaging/to220_1.html
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

--
Deep Friar: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms

"Jan Panteltje" <pNaonStpealmtje(a)yahoo.com> wrote in message news:i2cfeu$152$1(a)news.albasani.net...
> My old 7805 stabilisrs have 1.3 mm thick copper.
> The new ones I bought today are .5 mm.
> The new ones you can just bent with plyers, even break the tab off.
>
> Wonder when we go to .25 :-)
From: Nunya on 23 Jul 2010 13:41
On Jul 23, 9:19 am, Jan Panteltje <pNaonStpealm...(a)yahoo.com> wrote:
> My old 7805 stabilisrs have 1.3 mm thick copper.
> The new ones I bought today are .5 mm.
> The new ones you can just bent with plyers, even break the tab off.
>
> Wonder when we go to .25 :-)

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.
From: Jan Panteltje on 23 Jul 2010 14:33
On a sunny day (Fri, 23 Jul 2010 10:41:59 -0700 (PDT)) it happened Nunya
<jack_shephard(a)cox.net> wrote in
<1c4de387-f1c0-48cf-a9c4-bdf154b3bc2a(a)w31g2000yqb.googlegroups.com>:

>On Jul 23, 9:19�am, Jan Panteltje <pNaonStpealm...(a)yahoo.com> wrote:
>> My old 7805 stabilisrs have 1.3 mm thick copper.
>> The new ones I bought today are .5 mm.
>> The new ones you can just bent with plyers, even break the tab off.
>>
>> Wonder when we go to .25 :-)
>
> 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.

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
From: TTman on 23 Jul 2010 15:12

"Jan Panteltje" <pNaonStpealmtje(a)yahoo.com> wrote in message
news:i2cna2$ck1$1(a)news.albasani.net...
> On a sunny day (Fri, 23 Jul 2010 10:41:59 -0700 (PDT)) it happened Nunya
> <jack_shephard(a)cox.net> wrote in
> <1c4de387-f1c0-48cf-a9c4-bdf154b3bc2a(a)w31g2000yqb.googlegroups.com>:
>
>>On Jul 23, 9:19 am, Jan Panteltje <pNaonStpealm...(a)yahoo.com> wrote:
>>> My old 7805 stabilisrs have 1.3 mm thick copper.
>>> The new ones I bought today are .5 mm.

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


 |  Next  |  Last
Pages: 1 2 3
Prev: Relay Question
Next: Baxandall class D oscillator, can it produce a triangle likewaveform?