Well, it happened--the last fast PNP is EOL

Jim Thompson · Jun 5, 2018

On Tue, 05 Jun 2018 12:48:16 -0700, Joerg <news@analogconsultants.com>
wrote:

On 2018-06-05 12:27, Jim Thompson wrote:
On Tue, 05 Jun 2018 12:22:47 -0700, Joerg <news@analogconsultants.com
wrote:

On 2018-06-05 12:19, Jim Thompson wrote:
On Tue, 5 Jun 2018 18:38:27 +0000 (UTC), Uwe Bonnes
bon@hertz.tu-darmstadt.de> wrote:

John Larkin <jjlarkin@highlandtechnology.com> wrote:
..
I emailed ON and suggested they do some fast PNPs. They replied that
demand is too small.

I wondered that the military sector kept calm about the obsolation...

Most of my chip designs, transferred to Lansdale, are on the military
preferred components list... they seem to love unconditionally stable
OpAmps, even if the open-loop gain is only 75dB... though I'm sure the
sliding-class-A outputs and 10V/us slew-rates grab their attention as
well ;-)

Any radhard opamps in there with CM input range to the negative rail and
output to neg rail with pull-down? Will need that soon.

Not from my just-out-of-school era.

Today, I can easily design that for you... processing by X-Fab.

I'll find some off-the-shelf from "the usual suspects", was just
wondering if there was a genuine Thompson amp around in rad-hard.

Sometimes the just out of school designs are like VW Beetles. I have one
that runs off the conveyor belt since the 90's, now in Shenzhen, no end
in sight.

480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

Thinking outside the box... producing elegant solutions,
by understanding what nature is hiding.

"It is not in doing what you like, but in liking what you do that
is the secret of happiness." -James Barrie

Jim Thompson · Jun 5, 2018

On Tue, 5 Jun 2018 14:15:19 -0700 (PDT), pcdhobbs@gmail.com wrote:

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

[snip]

That's stretching history just a tweak... PNP's back then were
_laterals_ ... 1MHz GBW product, if you were lucky.

Right, and the NPNs were around 100 MHz. The fastest NPNs I have in my drawer are about 80 GHz, and the fastest PNPs other than the BFT92 are around 600 MHz. So we're back to a 100:1 ratio.

Just today I replaced a BFT92 in a customer design with a 2N3906ish cascode pair running at several times the current.

Barstids.

Phil Hobbs

480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

Thinking outside the box... producing elegant solutions,
by understanding what nature is hiding.

"It is not in doing what you like, but in liking what you do that
is the secret of happiness." -James Barrie

Jim Thompson · Jun 5, 2018

On Tue, 05 Jun 2018 13:09:16 -0700, John Larkin
<jjlarkin@highland_snip_technology.com> wrote:

On Tue, 5 Jun 2018 15:07:16 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 06/05/2018 01:29 PM, John Larkin wrote:
On Tue, 5 Jun 2018 10:56:25 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 06/04/2018 08:40 PM, Jim Thompson wrote:
On Mon, 4 Jun 2018 14:49:00 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:

mandag den 4. juni 2018 kl. 23.42.01 UTC+2 skrev Jim Thompson:
On 4 Jun 2018 14:04:31 -0700, Winfield Hill <hill@rowland.harvard.edu
wrote:

bitrex wrote...

Should start a s.e.d. fabless semiconductor company and get them made
again, China will make whatever you like. You could advertise it as
exactly that "The Last Fast PNP" like the Last of the Mohicans or something.

It's be nice to have it available in a SOT-323 SC70 package.

Maybe you and Hobbs should buy a wafer or two? Then, as time moves
on, package them to suit the era?

digikey has 18000 in stock, $2,835 for 15000 how many wafers can you get for that?

Discrete device wafers are dirt-cheap and low profitability. That's
why the devices are being phased out. Was anyone besides Hobbs buying
them?

...Jim Thompson

They sell for a lot more than digital transistors or BCX71s, and can't
be much harder to make. Nexperia didn't take NXP's rf transistors or
JFETs, so they're getting rid of them.

Cheers

Phil Hobbs

The EOL of discretes does keep fast circuit design interesting. GaN
parts are cheap and fast, but don't come in P-channel!

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

Cheers

Phil Hobbs

The PNP CK722 was the fastest transistor when I was a kid.

480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

Thinking outside the box... producing elegant solutions,
by understanding what nature is hiding.

"It is not in doing what you like, but in liking what you do that
is the secret of happiness." -James Barrie

John Larkin · Jun 5, 2018

On Tue, 5 Jun 2018 14:15:19 -0700 (PDT), pcdhobbs@gmail.com wrote:

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

[snip]

That's stretching history just a tweak... PNP's back then were
_laterals_ ... 1MHz GBW product, if you were lucky.

Right, and the NPNs were around 100 MHz. The fastest NPNs I have in my drawer are about 80 GHz, and the fastest PNPs other than the BFT92 are around 600 MHz. So we're back to a 100:1 ratio.

Just today I replaced a BFT92 in a customer design with a 2N3906ish cascode pair running at several times the current.

Barstids.

Phil Hobbs

ON has some PNPs up to 850 MHz. Medium fast.

--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

John Larkin · Jun 5, 2018

On Tue, 05 Jun 2018 12:24:56 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Tue, 5 Jun 2018 15:07:16 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

[snip]

The EOL of discretes does keep fast circuit design interesting. GaN
parts are cheap and fast, but don't come in P-channel!

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

[snip]

That's stretching history just a tweak... PNP's back then were
_laterals_ ... 1MHz GBW product, if you were lucky.

Point contact, Ft's measured in KHz. I think the first Touch-Tone
phones used point contact transistors.

Later parts were alloy junctions, then grown junctions.

--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

Jun 5, 2018

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

[snip]

That's stretching history just a tweak... PNP's back then were
_laterals_ ... 1MHz GBW product, if you were lucky.

Right, and the NPNs were around 100 MHz. The fastest NPNs I have in my drawer are about 80 GHz, and the fastest PNPs other than the BFT92 are around 600 MHz. So we're back to a 100:1 ratio.

Just today I replaced a BFT92 in a customer design with a 2N3906ish cascode pair running at several times the current.

Barstids.

Phil Hobbs

John Larkin · Jun 5, 2018

On Tue, 05 Jun 2018 14:22:45 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Tue, 05 Jun 2018 13:09:16 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:

On Tue, 5 Jun 2018 15:07:16 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 06/05/2018 01:29 PM, John Larkin wrote:
On Tue, 5 Jun 2018 10:56:25 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 06/04/2018 08:40 PM, Jim Thompson wrote:
On Mon, 4 Jun 2018 14:49:00 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:

mandag den 4. juni 2018 kl. 23.42.01 UTC+2 skrev Jim Thompson:
On 4 Jun 2018 14:04:31 -0700, Winfield Hill <hill@rowland.harvard.edu
wrote:

bitrex wrote...

Should start a s.e.d. fabless semiconductor company and get them made
again, China will make whatever you like. You could advertise it as
exactly that "The Last Fast PNP" like the Last of the Mohicans or something.

It's be nice to have it available in a SOT-323 SC70 package.

Maybe you and Hobbs should buy a wafer or two? Then, as time moves
on, package them to suit the era?

digikey has 18000 in stock, $2,835 for 15000 how many wafers can you get for that?

Discrete device wafers are dirt-cheap and low profitability. That's
why the devices are being phased out. Was anyone besides Hobbs buying
them?

...Jim Thompson

They sell for a lot more than digital transistors or BCX71s, and can't
be much harder to make. Nexperia didn't take NXP's rf transistors or
JFETs, so they're getting rid of them.

Cheers

Phil Hobbs

The EOL of discretes does keep fast circuit design interesting. GaN
parts are cheap and fast, but don't come in P-channel!

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

Cheers

Phil Hobbs

The PNP CK722 was the fastest transistor when I was a kid.

CK760/761... my father was a Raytheon wholesaler... that's what
twisted me away from architecture into electronics... toobs just
didn't have any sex appeal ;-)

...Jim Thompson

I liked tubes, partly because I got them free. The first thing I
designed professionally was a radiation counter that used those
circular-readout gas discharge tubes, Decatrons or something. I was
still in high school.

Exotic tubes were fun. Klystrons, thyratrons, PMTs, CRTs,
intensifiers, sniperscope imagers, flashtubes, acorns, high voltage,
weird RF jugs, like that. I wanted an xray tube but never got one.

I had an interview with a priggish guy; I told him that I liked tubes
because they were harder to blow up than transistors. He sniffed "that
won't do" and dismissed me. I said the same thing to the next guy and
he laughed and hired me. I designed over $100 million worth of stuff
for him.

--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

Gerhard Hoffmann · Jun 6, 2018

Am 05.06.2018 um 22:25 schrieb Joerg:

On 2018-06-05 13:07, Gerhard Hoffmann wrote:
Am 05.06.2018 um 21:22 schrieb Joerg:

Any radhard opamps in there with CM input range to the negative rail
and output to neg rail with pull-down? Will need that soon.

We did use lots of OP484Â

Though I am sure the taxpayer was ultimately on the hook for those

You must get used to a new set of cost metrics that is completely
different to that you are used to.

If it is on the qualified parts list, and it is available in less
than a year, choose it. You will probably build some engineering
samples and one flight sample. For the engineering samples, you can
use commercial parts. When a commercial quad op amp costs $5,
nobody cares. Just deciding to order ten of them costs more.

(Just kidding about you building the flight sample. I was allowed to
touch it to bring it up, but there was no soldering iron in the clean
room. They had quality controlled solder ladies for that.)

We had nice part decals that could accept both plastic SO-14 and the
ceramic flat packs for flight. It is important that this is done
according to flight board design rules, so you do not have to re-do
the board layout.

The cost of qualifying a new part will dwarf the part's commercial
price. Irradiation will cost a few grand, that's no problem. But you
must find someone to do the paperwork. That generates work for someone
higher in the hierarchy than you, and that is usually frowned upon.

I found it impossible to get a fast-ish JFET op amp for my 1:3000
pulse width stretcher. I finally gave up and designed around the
problem with discrete FETs. That exploded the area of the stretcher :-(
and it was ugly. Then they found they had leftover JFETs from a
previous mission, _please_ , can you use this type? Aaaarghhh, JFETs are
all individuals, even if they would not be of a different type.

Nobody will complain if you want 5 inductors of 470nH each.
But if you want 1 each of 330n, 390n, 470n, 560n... hell will break
loose. But you may not know in advance what your flight crystal
looks like electrically, and the inductance needed to pull it
to the right center frequency may vary.

Cheers, Gerhard

(ich bin jetzt ensthaft unterhopft!)

Joerg · Jun 6, 2018

On 2018-06-05 16:11, Gerhard Hoffmann wrote:

Am 05.06.2018 um 22:25 schrieb Joerg:
On 2018-06-05 13:07, Gerhard Hoffmann wrote:
Am 05.06.2018 um 21:22 schrieb Joerg:

Any radhard opamps in there with CM input range to the negative rail
and output to neg rail with pull-down? Will need that soon.

We did use lots of OP484

Though I am sure the taxpayer was ultimately on the hook for those

You must get used to a new set of cost metrics that is completely
different to that you are used to.

If it is on the qualified parts list, and it is available in less
than a year, choose it. You will probably build some engineering
samples and one flight sample. For the engineering samples, you can
use commercial parts. When a commercial quad op amp costs $5,
nobody cares. Just deciding to order ten of them costs more.

(Just kidding about you building the flight sample. I was allowed to
touch it to bring it up, but there was no soldering iron in the clean
room. They had quality controlled solder ladies for that.)

Yup, I am a bit familiar with that market. Now where it is going towards
the private sector cost begins to matter.

We had nice part decals that could accept both plastic SO-14 and the
ceramic flat packs for flight. It is important that this is done
according to flight board design rules, so you do not have to re-do
the board layout.

The cost of qualifying a new part will dwarf the part's commercial
price. Irradiation will cost a few grand, that's no problem. But you
must find someone to do the paperwork. That generates work for someone
higher in the hierarchy than you, and that is usually frowned upon.

Don't spoil someone's golf game by generating a lot of work

I found it impossible to get a fast-ish JFET op amp for my 1:3000
pulse width stretcher. I finally gave up and designed around the
problem with discrete FETs. That exploded the area of the stretcher :-(
and it was ugly. Then they found they had leftover JFETs from a
previous mission, _please_ , can you use this type? Aaaarghhh, JFETs are
all individuals, even if they would not be of a different type.

Nobody will complain if you want 5 inductors of 470nH each.
But if you want 1 each of 330n, 390n, 470n, 560n... hell will break
loose. But you may not know in advance what your flight crystal
looks like electrically, and the inductance needed to pull it
to the right center frequency may vary.

My stuff is all in the lower frequency domain, what you guys would
consider jittery DC.

Cheers, Gerhard

(ich bin jetzt ensthaft unterhopft!)

Come over here, I can help. I've got a Pliny the Elder clone in bottles
(not many left though) and another will be dry-hopped this week, then
again early next week. The Belgian Quadrupel also looks promising and
clocks in above 9% but that has to rest in the secondary fermenter and
then in bottles for another two months. Here is a Belgian Tripel blowing
off its Kraeusen:

http://www.analogconsultants.com/ng/brew/Blowoff.JPG

--
Regards, Joerg

http://www.analogconsultants.com/

Phil Hobbs · Jun 6, 2018

On 06/05/18 17:21, Jim Thompson wrote:

On Tue, 5 Jun 2018 14:15:19 -0700 (PDT), pcdhobbs@gmail.com wrote:

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

[snip]

That's stretching history just a tweak... PNP's back then were
_laterals_ ... 1MHz GBW product, if you were lucky.

Right, and the NPNs were around 100 MHz. The fastest NPNs I have in my drawer are about 80 GHz, and the fastest PNPs other than the BFT92 are around 600 MHz. So we're back to a 100:1 ratio.

Just today I replaced a BFT92 in a customer design with a 2N3906ish cascode pair running at several times the current.

Barstids.

Phil Hobbs

Should be only about 3:1, based on mobility. Wonder what the gotcha
is? Or is it that SiGe is only NPN?

Dunno. Germanium hole mobility is around 2000 cm**2/V/s, which is
higher than electron mobility in silicon, and dramatically higher than
silicon hole mobility.

I suspect that nobody expected people to design complementary circuits
that fast. I do a certain amount of gigahertz stuff, but lots of the
time I'm using superfast devices in unusual ways, e.g. my fave
pHEMT/SiGe NPN cascode, which I'd claim is the best wideband front end
building block out there.

BTW CEL have a bunch of newish pHEMTs to replace the late lamented
NE3509 etc.

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

Jun 6, 2018

On Tue, 05 Jun 2018 14:20:40 -0700, John Larkin
<jjlarkin@highland_snip_technology.com> wrote:

On Tue, 05 Jun 2018 12:24:56 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Tue, 5 Jun 2018 15:07:16 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

[snip]

The EOL of discretes does keep fast circuit design interesting. GaN
parts are cheap and fast, but don't come in P-channel!

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

[snip]

That's stretching history just a tweak... PNP's back then were
_laterals_ ... 1MHz GBW product, if you were lucky.

Point contact, Ft's measured in KHz. I think the first Touch-Tone
phones used point contact transistors.

Later parts were alloy junctions, then grown junctions.

IIRC, some car radios were implemented with tubes in RF/F stages but
transistors in audio stages.

Jun 6, 2018

On Wednesday, 6 June 2018 07:35:06 UTC+1, upsid...@downunder.com wrote:

On Tue, 05 Jun 2018 14:20:40 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:
On Tue, 05 Jun 2018 12:24:56 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Tue, 5 Jun 2018 15:07:16 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

[snip]

The EOL of discretes does keep fast circuit design interesting. GaN
parts are cheap and fast, but don't come in P-channel!

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

[snip]

That's stretching history just a tweak... PNP's back then were
_laterals_ ... 1MHz GBW product, if you were lucky.

Point contact, Ft's measured in KHz. I think the first Touch-Tone
phones used point contact transistors.

Later parts were alloy junctions, then grown junctions.

IIRC, some car radios were implemented with tubes in RF/F stages but
transistors in audio stages.

just one transistor for the output. Tubes could do the rest far cheaper.

NT

Phil Hobbs · Jun 6, 2018

On 06/05/18 15:07, Phil Hobbs wrote:

On 06/05/2018 01:29 PM, John Larkin wrote:
On Tue, 5 Jun 2018 10:56:25 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 06/04/2018 08:40 PM, Jim Thompson wrote:
On Mon, 4 Jun 2018 14:49:00 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:

mandag den 4. juni 2018 kl. 23.42.01 UTC+2 skrev Jim Thompson:
On 4 Jun 2018 14:04:31 -0700, Winfield Hill
hill@rowland.harvard.edu
wrote:

bitrex wrote...

Should start a s.e.d. fabless semiconductor company and get them
made
again, China will make whatever you like. You could advertise it as
exactly that "The Last Fast PNP" like the Last of the Mohicans
or something.

It's be nice to have it available in a SOT-323 SC70 package.

Maybe you and Hobbs should buy a wafer or two?Â Then, as time moves
on, package them to suit the era?

digikey has 18000 in stock, $2,835 for 15000 how many wafers can
you get for that?

Discrete device wafers are dirt-cheap and low profitability.Â That's
why the devices are being phased out.Â Was anyone besides Hobbs buying
them?

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â ...Jim Thompson

They sell for a lot more than digital transistors or BCX71s, and can't
be much harder to make.Â Nexperia didn't take NXP's rf transistors or
JFETs, so they're getting rid of them.

Cheers

Phil Hobbs

The EOL of discretes does keep fast circuit design interesting. GaN
parts are cheap and fast, but don't come in P-channel!

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

I've been digging around for the quickest PNPs still in production. The
champs seem to be the old Fairchild Process 65 parts: MMBT3640,
MMBT5771, and the discontinued PN4258. They come in at about 700 MHz
peak, but they're hard to get. Digikey wants $2 for the MMBT5771!

On Semi also has the fairly weirdly named 50A02SS, which is a bigger die
(400 mA vs 200), but is in plentiful supply.

The bootstrapped MMBT3906 follower worked for the customer, fortunately.

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

Jim Thompson · Jun 6, 2018

On Wed, 06 Jun 2018 09:35:01 +0300, upsidedown@downunder.com wrote:

On Tue, 05 Jun 2018 14:20:40 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:

On Tue, 05 Jun 2018 12:24:56 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Tue, 5 Jun 2018 15:07:16 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

[snip]

The EOL of discretes does keep fast circuit design interesting. GaN
parts are cheap and fast, but don't come in P-channel!

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

[snip]

That's stretching history just a tweak... PNP's back then were
_laterals_ ... 1MHz GBW product, if you were lucky.

Point contact, Ft's measured in KHz. I think the first Touch-Tone
phones used point contact transistors.

Later parts were alloy junctions, then grown junctions.

IIRC, some car radios were implemented with tubes in RF/F stages but
transistors in audio stages.

480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

Thinking outside the box... producing elegant solutions,
by understanding what nature is hiding.

"It is not in doing what you like, but in liking what you do that
is the secret of happiness." -James Barrie

Neon John · Jun 8, 2018

On Tue, 05 Jun 2018 15:01:50 -0700, John Larkin
<jjlarkin@highland_snip_technology.com> wrote:

Exotic tubes were fun. Klystrons, thyratrons, PMTs, CRTs,
intensifiers, sniperscope imagers, flashtubes, acorns, high voltage,
weird RF jugs, like that. I wanted an xray tube but never got one.

Want an X-ray tube now? I have a dental tube with a blown filament.
Won't work, of course, but is sure is pretty. All that polished,
non-oxidized copper in there plus the glass envelope that is nicely
solarized from long use. Free if you want it.

John

John DeArmond
http://www.neon-john.com
http://www.tnduction.com
Tellico Plains, Occupied TN
See website for email address

Klaus Kragelund · Jun 8, 2018

On Tuesday, June 5, 2018 at 9:14:45 PM UTC+2, Jim Thompson wrote:

On Mon, 4 Jun 2018 23:18:16 -0400, "tom" <tmiller11147@verizon.net
wrote:

"Jim Thompson" <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote in
message news:4psbhdloovifoq9s67h0n5s734e374g5vc@4ax.com...
On Mon, 04 Jun 2018 18:02:47 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:

On Mon, 04 Jun 2018 17:40:05 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Mon, 4 Jun 2018 14:49:00 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:

mandag den 4. juni 2018 kl. 23.42.01 UTC+2 skrev Jim Thompson:
On 4 Jun 2018 14:04:31 -0700, Winfield Hill <hill@rowland.harvard.edu
wrote:

bitrex wrote...

Should start a s.e.d. fabless semiconductor company and get them
made
again, China will make whatever you like. You could advertise it as
exactly that "The Last Fast PNP" like the Last of the Mohicans or
something.

It's be nice to have it available in a SOT-323 SC70 package.

Maybe you and Hobbs should buy a wafer or two? Then, as time moves
on, package them to suit the era?

digikey has 18000 in stock, $2,835 for 15000 how many wafers can you get
for that?

Discrete device wafers are dirt-cheap and low profitability. That's
why the devices are being phased out. Was anyone besides Hobbs buying
them?

...Jim Thompson

I sure was. And a lot of SOT-89 parts, now gone too.

If the wafers are cheap, somebody could bake a crate full of them,
jack up the device prices, and do OK. And not annoy a lot of
maybe-future customers.

Look into it. Lansdale bought a lot of the rights to Moto chips...
still selling some I designed 50+ years ago.

...Jim Thompson
--

Jim, you should post a list of all the chips you designed.

Regards

There aren't that many... just 18 standard products between 1962 and
1970.... and they are listed on my home page, toward the bottom.

At 1970 I fled the corporate political world (I couldn't deal with all
the political BS at Motorola... I think I quit 4-times just to force
proper engineering decisions) and went to doing virtually all
custom... with a few exceptions, like the LVDS chips for Fairchild.

(I supported my family at the time... 1970-1977, by running a hybrid
line at Dickson Electronics and writing a lot of the course material
for ICE... Integrated Circuit Engineering.)

At last count there were ~200 custom chips. I'll have to ponder and
see if I can devise a non-disclosure way of listing those devices...
and what they do functionally... if I can I'll post and announce.

In the last five years or so I've tired of chip design... there really
isn't anything analog I haven't done before >:-}... so I've hopped
into Behavioral Modeling... easy for me since I've done so much
circuit work (and my math capabilities, at least up thru Calculus, are
superb)... and it's fun, devising functional models which don't
divulge any internal IP... a lot like puzzle solving in reverse ;-)

Jim, I hope you won't be too tired about chip design. We will be asking you very soon to start the ASIC design we discussed.

Exiting for me, first ASIC

Cheers

Klaus

Lasse Langwadt Christense · Jun 9, 2018

lĂ¸rdag den 9. juni 2018 kl. 00.50.50 UTC+2 skrev John Larkin:

On Tue, 05 Jun 2018 12:14:32 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Mon, 4 Jun 2018 23:18:16 -0400, "tom" <tmiller11147@verizon.net
wrote:

"Jim Thompson" <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote in
message news:4psbhdloovifoq9s67h0n5s734e374g5vc@4ax.com...
On Mon, 04 Jun 2018 18:02:47 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:

On Mon, 04 Jun 2018 17:40:05 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Mon, 4 Jun 2018 14:49:00 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:

mandag den 4. juni 2018 kl. 23.42.01 UTC+2 skrev Jim Thompson:
On 4 Jun 2018 14:04:31 -0700, Winfield Hill <hill@rowland.harvard..edu
wrote:

bitrex wrote...

Should start a s.e.d. fabless semiconductor company and get them
made
again, China will make whatever you like. You could advertise it as
exactly that "The Last Fast PNP" like the Last of the Mohicans or
something.

It's be nice to have it available in a SOT-323 SC70 package.

Maybe you and Hobbs should buy a wafer or two? Then, as time moves
on, package them to suit the era?

digikey has 18000 in stock, $2,835 for 15000 how many wafers can you get
for that?

Discrete device wafers are dirt-cheap and low profitability. That's
why the devices are being phased out. Was anyone besides Hobbs buying
them?

...Jim Thompson

I sure was. And a lot of SOT-89 parts, now gone too.

If the wafers are cheap, somebody could bake a crate full of them,
jack up the device prices, and do OK. And not annoy a lot of
maybe-future customers.

Look into it. Lansdale bought a lot of the rights to Moto chips...
still selling some I designed 50+ years ago.

...Jim Thompson
--

Jim, you should post a list of all the chips you designed.

Regards

There aren't that many... just 18 standard products between 1962 and
1970.... and they are listed on my home page, toward the bottom.

At 1970 I fled the corporate political world (I couldn't deal with all
the political BS at Motorola... I think I quit 4-times just to force
proper engineering decisions) and went to doing virtually all
custom... with a few exceptions, like the LVDS chips for Fairchild.

(I supported my family at the time... 1970-1977, by running a hybrid
line at Dickson Electronics and writing a lot of the course material
for ICE... Integrated Circuit Engineering.)

I hung out a bit with a giant jolly guy in Seattle who was the ICE rep
there. He gave me a few of their secret chip analysies, lots of cool
color micrographs. Can't remember his name just now.

if you like die picture there's lots here, https://zeptobars.com/en/

John Larkin · Jun 9, 2018

On Tue, 5 Jun 2018 22:20:19 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 06/05/18 17:21, Jim Thompson wrote:
On Tue, 5 Jun 2018 14:15:19 -0700 (PDT), pcdhobbs@gmail.com wrote:

Yeah, it's like doing chip design circa 1975--the NPNs are 100 times
faster than the PNPs.

[snip]

That's stretching history just a tweak... PNP's back then were
_laterals_ ... 1MHz GBW product, if you were lucky.

Right, and the NPNs were around 100 MHz. The fastest NPNs I have in my drawer are about 80 GHz, and the fastest PNPs other than the BFT92 are around 600 MHz. So we're back to a 100:1 ratio.

Just today I replaced a BFT92 in a customer design with a 2N3906ish cascode pair running at several times the current.

Barstids.

Phil Hobbs

Should be only about 3:1, based on mobility. Wonder what the gotcha
is? Or is it that SiGe is only NPN?

Dunno. Germanium hole mobility is around 2000 cm**2/V/s, which is
higher than electron mobility in silicon, and dramatically higher than
silicon hole mobility.

I suspect that nobody expected people to design complementary circuits
that fast. I do a certain amount of gigahertz stuff, but lots of the
time I'm using superfast devices in unusual ways, e.g. my fave
pHEMT/SiGe NPN cascode, which I'd claim is the best wideband front end
building block out there.

BTW CEL have a bunch of newish pHEMTs to replace the late lamented
NE3509 etc.

Good news. We use a lot of NE3508 and NE3509 in some older products,
mostly to reset timing ramps. I do that other ways for new designs.

--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

John Larkin · Jun 9, 2018

On Tue, 05 Jun 2018 12:14:32 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Mon, 4 Jun 2018 23:18:16 -0400, "tom" <tmiller11147@verizon.net
wrote:

"Jim Thompson" <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote in
message news:4psbhdloovifoq9s67h0n5s734e374g5vc@4ax.com...
On Mon, 04 Jun 2018 18:02:47 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:

On Mon, 04 Jun 2018 17:40:05 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Mon, 4 Jun 2018 14:49:00 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:

mandag den 4. juni 2018 kl. 23.42.01 UTC+2 skrev Jim Thompson:
On 4 Jun 2018 14:04:31 -0700, Winfield Hill <hill@rowland.harvard.edu
wrote:

bitrex wrote...

Should start a s.e.d. fabless semiconductor company and get them
made
again, China will make whatever you like. You could advertise it as
exactly that "The Last Fast PNP" like the Last of the Mohicans or
something.

It's be nice to have it available in a SOT-323 SC70 package.

Maybe you and Hobbs should buy a wafer or two? Then, as time moves
on, package them to suit the era?

digikey has 18000 in stock, $2,835 for 15000 how many wafers can you get
for that?

Discrete device wafers are dirt-cheap and low profitability. That's
why the devices are being phased out. Was anyone besides Hobbs buying
them?

...Jim Thompson

I sure was. And a lot of SOT-89 parts, now gone too.

If the wafers are cheap, somebody could bake a crate full of them,
jack up the device prices, and do OK. And not annoy a lot of
maybe-future customers.

Look into it. Lansdale bought a lot of the rights to Moto chips...
still selling some I designed 50+ years ago.

...Jim Thompson
--

Jim, you should post a list of all the chips you designed.

Regards

There aren't that many... just 18 standard products between 1962 and
1970.... and they are listed on my home page, toward the bottom.

At 1970 I fled the corporate political world (I couldn't deal with all
the political BS at Motorola... I think I quit 4-times just to force
proper engineering decisions) and went to doing virtually all
custom... with a few exceptions, like the LVDS chips for Fairchild.

(I supported my family at the time... 1970-1977, by running a hybrid
line at Dickson Electronics and writing a lot of the course material
for ICE... Integrated Circuit Engineering.)

I hung out a bit with a giant jolly guy in Seattle who was the ICE rep
there. He gave me a few of their secret chip analysies, lots of cool
color micrographs. Can't remember his name just now.

--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

Jim Thompson · Jun 9, 2018

On Fri, 08 Jun 2018 15:50:38 -0700, John Larkin
<jjlarkin@highland_snip_technology.com> wrote:

On Tue, 05 Jun 2018 12:14:32 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Mon, 4 Jun 2018 23:18:16 -0400, "tom" <tmiller11147@verizon.net
wrote:

"Jim Thompson" <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote in
message news:4psbhdloovifoq9s67h0n5s734e374g5vc@4ax.com...
On Mon, 04 Jun 2018 18:02:47 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:

On Mon, 04 Jun 2018 17:40:05 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Mon, 4 Jun 2018 14:49:00 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:

mandag den 4. juni 2018 kl. 23.42.01 UTC+2 skrev Jim Thompson:
On 4 Jun 2018 14:04:31 -0700, Winfield Hill <hill@rowland.harvard.edu
wrote:

bitrex wrote...

Should start a s.e.d. fabless semiconductor company and get them
made
again, China will make whatever you like. You could advertise it as
exactly that "The Last Fast PNP" like the Last of the Mohicans or
something.

It's be nice to have it available in a SOT-323 SC70 package.

Maybe you and Hobbs should buy a wafer or two? Then, as time moves
on, package them to suit the era?

digikey has 18000 in stock, $2,835 for 15000 how many wafers can you get
for that?

Discrete device wafers are dirt-cheap and low profitability. That's
why the devices are being phased out. Was anyone besides Hobbs buying
them?

...Jim Thompson

I sure was. And a lot of SOT-89 parts, now gone too.

If the wafers are cheap, somebody could bake a crate full of them,
jack up the device prices, and do OK. And not annoy a lot of
maybe-future customers.

Look into it. Lansdale bought a lot of the rights to Moto chips...
still selling some I designed 50+ years ago.

...Jim Thompson
--

Jim, you should post a list of all the chips you designed.

Regards

There aren't that many... just 18 standard products between 1962 and
1970.... and they are listed on my home page, toward the bottom.

At 1970 I fled the corporate political world (I couldn't deal with all
the political BS at Motorola... I think I quit 4-times just to force
proper engineering decisions) and went to doing virtually all
custom... with a few exceptions, like the LVDS chips for Fairchild.

(I supported my family at the time... 1970-1977, by running a hybrid
line at Dickson Electronics and writing a lot of the course material
for ICE... Integrated Circuit Engineering.)

I hung out a bit with a giant jolly guy in Seattle who was the ICE rep
there. He gave me a few of their secret chip analysies, lots of cool
color micrographs. Can't remember his name just now.

480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

Thinking outside the box... producing elegant solutions,
by understanding what nature is hiding.

"It is not in doing what you like, but in liking what you do that
is the secret of happiness." -James Barrie

Well, it happened--the last fast PNP is EOL

Jim Thompson

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