awesome

[Jim Thompson]

On Tue, 28 Mar 2006 09:54:04 -0800, John Larkin

[snip]>>year or so.

The rep dropped off an eval board here, with a gadget on it. He claims
we can get parts, but these exotic semiconductors do always seem to be
six months off. They've added a "P" in the front of the part number,
on the pdf datasheet, and he claims that means "production." We'll
see.

When/if we can get them, they will be a pretty radical change to the
way people design wideband RF power amps.

John

"P" means prototypes available ;-)

...Jim Thompson

 

[Jim Thompson]

On Tue, 28 Mar 2006 09:54:04 -0800, John Larkin

[snip]>>year or so.

The rep dropped off an eval board here, with a gadget on it. He claims
we can get parts, but these exotic semiconductors do always seem to be
six months off. They've added a "P" in the front of the part number,
on the pdf datasheet, and he claims that means "production." We'll
see.

When/if we can get them, they will be a pretty radical change to the
way people design wideband RF power amps.

John

"P" means prototypes available ;-)

...Jim Thompson

Or PRELIMINARY ;-)

...Jim Thompson

 

[Roy L. Fuchs]

The rep dropped off an eval board here, with a gadget on it. He claims
we can get parts, but these exotic semiconductors do always seem to be
six months off. They've added a "P" in the front of the part number,
on the pdf datasheet, and he claims that means "production." We'll
see.

When/if we can get them, they will be a pretty radical change to the
way people design wideband RF power amps.

It would seem that the minimum order would require having an "M"
suffix in the "quantity field".

Did he charge you for the eval board? Did you see their other Gallium
Nitride product? The Ten Watt chip? It also looks pretty tight.

 

[Fred Bartoli]

On Tue, 28 Mar 2006 09:54:04 -0800, John Larkin

[snip]>>year or so.

The rep dropped off an eval board here, with a gadget on it. He claims
we can get parts, but these exotic semiconductors do always seem to be
six months off. They've added a "P" in the front of the part number,
on the pdf datasheet, and he claims that means "production." We'll
see.

When/if we can get them, they will be a pretty radical change to the
way people design wideband RF power amps.

John

"P" means prototypes available ;-)

...Jim Thompson

Or PRELIMINARY ;-)

Or Pray_to_have_it.

 

[Roy L. Fuchs]

On Tue, 28 Mar 2006 09:54:04 -0800, John Larkin

[snip]>>year or so.

The rep dropped off an eval board here, with a gadget on it. He claims
we can get parts, but these exotic semiconductors do always seem to be
six months off. They've added a "P" in the front of the part number,
on the pdf datasheet, and he claims that means "production." We'll
see.

When/if we can get them, they will be a pretty radical change to the
way people design wideband RF power amps.

John



"P" means prototypes available ;-)

...Jim Thompson

Or PRELIMINARY ;-)

Or Pray_to_have_it.

These guys make some pretty good devices as well.

http://www.zetex.com/

 

[Rich Grise]

http://www.nitronex.com/solutions/NPT35050 RF Power Transistor V1.3.pdf

So, are you going to build a pocket microwave oven, or what? ;-)

Cheers!
Rich

 

[Rich Grise]

Seems kind of open-ended. Surely if these guys can hear a staggering
difference between cheap and expensive AC line sockets, response well into
the hundreds of MHz may not be overkill.

Well, if it can "switch" at 3.3~3.5 GHz, it sounds like a natural for
class D; you wouldn't need much of a Nyquist filter. ;-)

Cheers!
Rich

 

[Rich Grise]

On Tue, 28 Mar 2006 09:54:04 -0800, John Larkin

[snip]>>year or so.

The rep dropped off an eval board here, with a gadget on it. He claims we
can get parts, but these exotic semiconductors do always seem to be six
months off. They've added a "P" in the front of the part number, on the
pdf datasheet, and he claims that means "production." We'll see.

When/if we can get them, they will be a pretty radical change to the way
people design wideband RF power amps.

John

"P" means prototypes available ;-)

...Jim Thompson

Silly me! I thought it meant "plastic". ;-)

Cheers!
Rich

 

[Jim Thompson]

On Tue, 28 Mar 2006 09:54:04 -0800, John Larkin

[snip]>>year or so.

The rep dropped off an eval board here, with a gadget on it. He claims we
can get parts, but these exotic semiconductors do always seem to be six
months off. They've added a "P" in the front of the part number, on the
pdf datasheet, and he claims that means "production." We'll see.

When/if we can get them, they will be a pretty radical change to the way
people design wideband RF power amps.

John

"P" means prototypes available ;-)

...Jim Thompson

Silly me! I thought it meant "plastic". ;-)

Cheers!
Rich

"P" for "plastic" is usually a SUFFIX not a PREFIX.

...Jim Thompson

 

[Rich Grise]

The frequency isn't high enough. I need to make a crystal controlled
3.XXXXXX*10^14Hz signal. I'd take a lower power though.

Isn't that like a 1000 nanometer wavelength? Why not just get a CO2 laser?

Or maybe slap together a little MEMS klystron or something. ;-)

Cheers!
Rich

 

[Fred Bartoli]

On Tue, 28 Mar 2006 09:54:04 -0800, John Larkin

[snip]>>year or so.

The rep dropped off an eval board here, with a gadget on it. He claims we
can get parts, but these exotic semiconductors do always seem to be six
months off. They've added a "P" in the front of the part number, on the
pdf datasheet, and he claims that means "production." We'll see.

When/if we can get them, they will be a pretty radical change to the way
people design wideband RF power amps.

John



"P" means prototypes available ;-)

...Jim Thompson

Silly me! I thought it meant "plastic". ;-)

Cheers!
Rich

"P" for "plastic" is usually a SUFFIX not a PREFIX.

By those VIH times, it's much better to have palstic as prefix than as
suffix.

 

[Tim Williams]

So, are you going to build a pocket microwave oven, or what? ;-)

^ ^
Good way to keep people from ejaculating into the gene pool I suppose.
;-)

Tim

 

[John Larkin]

Did he charge you for the eval board?

No, it's on loan for a few weeks. The eval board is tuned for the 3.4
GHz band, but the fet is clamp-mounted, so we've pulled it to make
measurements. Looks like gate capacitance is about 200 pF, less than a
tenth that of a comparable RF mosfet. This looks promising.

Did you see their other Gallium
Nitride product? The Ten Watt chip? It also looks pretty tight.

Yeah. And they're working on some other neat-sounding stuff.

I was sorta getting excited about the SiC fets, until I got
datasheets. High voltage, yeah, but they behave more like tubes, with
pinchoff voltages like, maybe, -20, which gives pitiful
transconductances.

John

 

[Ken Smith]

Isn't that like a 1000 nanometer wavelength? Why not just get a CO2 laser?

Its hard to lock a CO2 laser to the multiple of a crystal.

Or maybe slap together a little MEMS klystron or something. ;-)

I like it!

 

[Phil Hobbs]

I'll sell you a nice phase detector for your PLL.

Cheers,

Phil Hobbs

 

[John Larkin]

I'll sell you a nice phase detector for your PLL.

Cheers,

Phil Hobbs

Has anyone actually locked an optical oscillator to an electrical
oscillator, one way or the other?

John

 

[Phil Hobbs]

Has anyone actually locked an optical oscillator to an electrical
oscillator, one way or the other?

Sure. The Hall/Haensch optical comb generator makes it pretty easy
actually--you take a femtosecond laser, whose rep rate is set by its
cavity length, and put it through a nonlinear holey fibre to spread it
way, way out in frequency--a forest of spikes extending all the way to
dc, in principle, incredibly accurately related harmonically (unlike the
laser modes themselves, which always show some dispersion). You can
phaselock the rep rate and pick out any harmonic you like.

Just like an old-time ham's crystal frequency marker generator, only at
400 THz.

Cheers,

Phil Hobbs

 

[John Larkin]

http://www.nitronex.com/solutions/NPT35050 RF Power Transistor V1.3.pdf


John

Well, we blew it up, trying to measure Cd vs various voltages. So of
course we opened up the can. The fet part itself is tiny, and what's
inside is mostly gate matching network. From the gate blade, it's
essentially L-C-L-C-L-Gate, where the Ls are various wirebond loops.

I'm guessing the matching stuff doubles the gate capacitance so if we
can get an unmatched part, it will really scream.

John

 

[Tim Williams]

http://www.nitronex.com/solutions/NPT35050 RF Power Transistor V1.3.
pdf

so does it glow blue when it's working?

That would be 730THz, not 3GHz.

Of course you mean the GaN semiconductor, which I wouldn't think so because
it probably isn't doped right and isn't forward-biased? (Channel is
effectively resistive, not conducting across a junction, and the body diode
(if any) or gate diode is reverse-biased... plus it's probably in a boring
black plastic case.

Speaking of doping, what's the difference between an LED and diode, anyway,
band gap (and Vf) aside?

Tim

 

[Joel Kolstad]

Any chance you'd post some pictures of the guts for us?