The EPC fets are great electrically, but are a major pain to use. One
has to lay out a board and do all the stencil/reflow stuff just to
prototype.

https://www.dropbox.com/s/9mv0czf0keyp1b6/EPC2038.jpg?raw=1

https://www.dropbox.com/s/xmkwagcqsf8vaqe/EPC2037.jpg?raw=1

--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

jlarkin@highlandsniptechnology.com wrote:
> The EPC fets are great electrically, but are a major pain to use. One
> has to lay out a board and do all the stencil/reflow stuff just to
> prototype.
>
> https://www.dropbox.com/s/9mv0czf0keyp1b6/EPC2038.jpg?raw=1
>
> https://www.dropbox.com/s/xmkwagcqsf8vaqe/EPC2037.jpg?raw=1

To be fair, for their intended application there's a premium on
sub-nanohenry inductances. I reverse-engineered the drive circuit of a
long-range vehicular lidar a few years back--it had one of those FETs
dumping a few-nanofarad capacitor charged to ~40V into a triple-stacked
diode laser, producing a pulse of several amps, about 5 ns wide.

I measured the waveforms and made an LTspice model that matched
extremely well--200 pH in the drain and 180 pH in the source, for a
total of less than 400 pH for the entire circuit. (And all at pH 7. ) ;)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

Am 02.06.21 um 17:49 schrieb jlarkin@highlandsniptechnology.com:
> The EPC fets are great electrically, but are a major pain to use. One
> has to lay out a board and do all the stencil/reflow stuff just to
> prototype.
>
> https://www.dropbox.com/s/9mv0czf0keyp1b6/EPC2038.jpg?raw=1
>
> https://www.dropbox.com/s/xmkwagcqsf8vaqe/EPC2037.jpg?raw=1

I did solder them in with just a little bit of hot air.
Very little, or you won't find them again.

It was surprisingly easy.

< https://www.flickr.com/photos/137684711@N07/51003999496/in/datetaken/

Gerhard

onsdag den 2. juni 2021 kl. 19.15.02 UTC+2 skrev Gerhard Hoffmann:
> Am 02.06.21 um 17:49 schrieb jla...@highlandsniptechnology.com:
> > The EPC fets are great electrically, but are a major pain to use. One
> > has to lay out a board and do all the stencil/reflow stuff just to
> > prototype.
> >
> > https://www.dropbox.com/s/9mv0czf0keyp1b6/EPC2038.jpg?raw=1
> >
> > https://www.dropbox.com/s/xmkwagcqsf8vaqe/EPC2037.jpg?raw=1
> I did solder them in with just a little bit of hot air.
> Very little, or you won't find them again.

or maybe a hot plate?

You might get a pcb, or part of one, an make some size converters
similar to the surface mount to dip in concept. Considering the
numbers Phill mentioned, you'd probably need to exercise
care. A nice group of .25 by .375 inch pcbs with the fets mounted
and ready to be diced and soldered edgewise up to larger boards.

Hul

jlarkin@highlandsniptechnology.com wrote:
> The EPC fets are great electrically, but are a major pain to use. One
> has to lay out a board and do all the stencil/reflow stuff just to
> prototype.

> https://www.dropbox.com/s/9mv0czf0keyp1b6/EPC2038.jpg?raw=1

> https://www.dropbox.com/s/xmkwagcqsf8vaqe/EPC2037.jpg?raw=1

> --

> John Larkin Highland Technology, Inc

> The best designs are necessarily accidental.

>

On Thu, 3 Jun 2021 22:31:58 +0000 (UTC), Hul Tytus <ht@panix.com>
wrote:

>You might get a pcb, or part of one, an make some size converters
>similar to the surface mount to dip in concept. Considering the
>numbers Phill mentioned, you'd probably need to exercise
>care. A nice group of .25 by .375 inch pcbs with the fets mounted
>and ready to be diced and soldered edgewise up to larger boards.
>
>Hul

We did make some adapter boards, to experiment with the parts.

https://www.dropbox.com/s/8fkv6v4cvea1m8m/Gan_Tiles.JPG?raw=1

https://www.dropbox.com/s/01amd9x0kqh6qho/EPC_Breakouts.JPG?raw=1

EPC's Spice models are pretty good, which helps avoid breadboarding
and iteration. EPC is adamant about never packaging these parts, or
supplying adapters for testing.

I've done a few mouse-bite baby boards with the EPC parts and drivers
and such, as throw-aways in case we blow one up.

https://www.dropbox.com/s/q81306jpbndwnmw/T52C_Glob.JPG?raw=1

https://www.dropbox.com/s/tmrhwzeuuz3g7f1/T577_panel_back.JPG?raw=1

These parts are very fragile. A mild touch can fracture a corner, or
break the fet off the board and leave its balls behind. So it's best
to glob-top them, and then they are impossible to rework.

--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

John - you sound well ahead of what I suggested. Those tiny packages
are truelly approaching die size devices.

Hul

jlarkin@highlandsniptechnology.com wrote:
> On Thu, 3 Jun 2021 22:31:58 +0000 (UTC), Hul Tytus <ht@panix.com>
> wrote:

> >You might get a pcb, or part of one, an make some size converters
> >similar to the surface mount to dip in concept. Considering the
> >numbers Phill mentioned, you'd probably need to exercise
> >care. A nice group of .25 by .375 inch pcbs with the fets mounted
> >and ready to be diced and soldered edgewise up to larger boards.
> >
> >Hul

> We did make some adapter boards, to experiment with the parts.

> https://www.dropbox.com/s/8fkv6v4cvea1m8m/Gan_Tiles.JPG?raw=1

> https://www.dropbox.com/s/01amd9x0kqh6qho/EPC_Breakouts.JPG?raw=1

> EPC's Spice models are pretty good, which helps avoid breadboarding
> and iteration. EPC is adamant about never packaging these parts, or
> supplying adapters for testing.

> I've done a few mouse-bite baby boards with the EPC parts and drivers
> and such, as throw-aways in case we blow one up.

> https://www.dropbox.com/s/q81306jpbndwnmw/T52C_Glob.JPG?raw=1

> https://www.dropbox.com/s/tmrhwzeuuz3g7f1/T577_panel_back.JPG?raw=1

> These parts are very fragile. A mild touch can fracture a corner, or
> break the fet off the board and leave its balls behind. So it's best
> to glob-top them, and then they are impossible to rework.

> --

> John Larkin Highland Technology, Inc

> The best designs are necessarily accidental.

>

On Fri, 4 Jun 2021 20:32:23 +0000 (UTC), Hul Tytus <ht@panix.com>
wrote:

>John - you sound well ahead of what I suggested. Those tiny packages
>are truelly approaching die size devices.
>
>Hul

Mechanically, they are horrendous. But electrically, they are magical,
and replace bipolars and mesfets and phemts that are EOL now.

Cheap, too.

Here's a 25 volt pulse into 50 ohms, from a 50 volt supply, a totem
pole of two of the tiny 4-ball parts.

https://www.dropbox.com/s/izvf0thpe5ddty9/T577B_Vp50.JPG?raw=1

Gerhard Hoffmann wrote:
> Am 02.06.21 um 17:49 schrieb jlarkin@highlandsniptechnology.com:
>> The EPC fets are great electrically, but are a major pain to use. One
>> has to lay out a board and do all the stencil/reflow stuff just to
>> prototype.
>>
>> https://www.dropbox.com/s/9mv0czf0keyp1b6/EPC2038.jpg?raw=1
>>
>> https://www.dropbox.com/s/xmkwagcqsf8vaqe/EPC2037.jpg?raw=1
>
>
> I did solder them in with just a little bit of hot air.
> Very little, or you won't find them again.

Dr Fauci says to wear a mask so you don't blow them away with your
breath.

--
Defund the Thought Police

On Wed, 02 Jun 2021 08:49:45 -0700, jlarkin@highlandsniptechnology.com
wrote:

>The EPC fets are great electrically, but are a major pain to use. One
>has to lay out a board and do all the stencil/reflow stuff just to
>prototype.
>
>https://www.dropbox.com/s/9mv0czf0keyp1b6/EPC2038.jpg?raw=1

What did that poor FET ever do to you?

On Sat, 05 Jun 2021 16:51:42 +0100, Cursitor Doom <cd@nowhere.com>
wrote:

>On Wed, 02 Jun 2021 08:49:45 -0700, jlarkin@highlandsniptechnology.com
>wrote:
>
>>The EPC fets are great electrically, but are a major pain to use. One
>>has to lay out a board and do all the stencil/reflow stuff just to
>>prototype.
>>
>>https://www.dropbox.com/s/9mv0czf0keyp1b6/EPC2038.jpg?raw=1
>
>What did that poor FET ever do to you?

I don't abuse innocent baby ganfets. That's just the way it came, next
to an 0603 resistor for scale.

--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.