On Tue, 07 Feb 2023 07:01:57 GMT, Jan Panteltje <alien@comet.invalid> wrote:>On a sunny day (Mon, 06 Feb 2023 09:47:57 -0800) it happened John Larkin ><jlarkin@highlandSNIPMEtechnology.com> wrote in ><7qe2uh9mv99o5pt91in5j1j9b4drqqirrg@4ax.com>: > >> >>https://www.qorvo.com/products/p/QPD1016 >> >>The part could be very useful in wideband/pulse applications [1] but >>there are no DC curves, no capacitances, no Spice models, just the >>silly load pull cartoons. >> >>[1] except for the price of course. >> > >Bit puzzled by the bias on - bias off sequence for the test board... >page 20 pfd >How critical is that? >Needs some external circuits..It's fiddle-biased. One needs to be careful to not blow it up. Envision blowing up a lot of parts on the test fixture, at $1K each. It's interesting that Id-max is 70 amps but they set the current limited supply to 1.1. In a real amp, presumably there would be a servo loop to sense Id and set the gate bias voltage, and sequence everything properly. A Spice model would be the way to develop that! I wonder if the gate is a diode to the source, and how that behaves. Presumably it is a depletion fet. Idss is of course not a measurement that the RF types don't understand. The EPC GaN fets are great and they have Spice models that mostly work. Their gate behavior is interesting. I use the SAV-5xx parts in time domain, as switches, and they have at least some DC curves on their data sheets; I've measured more. MiniCircuits promises to never offer a Spice model. "The easiest thing in the world is not to sell." - Melvin Goldstein
another RF part rant
Started by ●February 6, 2023
Reply by ●February 7, 20232023-02-07
Reply by ●February 7, 20232023-02-07
Am 07.02.23 um 16:47 schrieb John Larkin:> On Tue, 07 Feb 2023 07:01:57 GMT, Jan Panteltje <alien@comet.invalid> > wrote: > >> On a sunny day (Mon, 06 Feb 2023 09:47:57 -0800) it happened John Larkin >> <jlarkin@highlandSNIPMEtechnology.com> wrote in >> <7qe2uh9mv99o5pt91in5j1j9b4drqqirrg@4ax.com>: >> >>> >>> https://www.qorvo.com/products/p/QPD1016 >>> >>> The part could be very useful in wideband/pulse applications [1] but >>> there are no DC curves, no capacitances, no Spice models, just the >>> silly load pull cartoons. >>> >>> [1] except for the price of course. >>> >> >> Bit puzzled by the bias on - bias off sequence for the test board... >> page 20 pfd >> How critical is that? >> Needs some external circuits.. > > It's fiddle-biased. One needs to be careful to not blow it up. > Envision blowing up a lot of parts on the test fixture, at $1K each. > > It's interesting that Id-max is 70 amps but they set the current > limited supply to 1.1. > > In a real amp, presumably there would be a servo loop to sense Id and > set the gate bias voltage, and sequence everything properly. A Spice > model would be the way to develop that! > > I wonder if the gate is a diode to the source, and how that behaves. > Presumably it is a depletion fet. Idss is of course not a measurement > that the RF types don't understand. > > The EPC GaN fets are great and they have Spice models that mostly > work. Their gate behavior is interesting. > > I use the SAV-5xx parts in time domain, as switches, and they have at > least some DC curves on their data sheets; I've measured more. > MiniCircuits promises to never offer a Spice model. > > "The easiest thing in the world is not to sell." > > - Melvin Goldstein >< https://www.modelithics.com/MVP/Qorvo?comp_id=Qorvo&tab=3 > < https://www.qorvo.com/products/p/QPD1016#documents > < https://www.qorvo.com/products/p/QPD1016#evaluation-tools > cheers, Gerhard
Reply by ●February 7, 20232023-02-07
On Tue, 7 Feb 2023 17:04:15 +0100, Gerhard Hoffmann <dk4xp@arcor.de> wrote:>Am 07.02.23 um 16:47 schrieb John Larkin: >> On Tue, 07 Feb 2023 07:01:57 GMT, Jan Panteltje <alien@comet.invalid> >> wrote: >> >>> On a sunny day (Mon, 06 Feb 2023 09:47:57 -0800) it happened John Larkin >>> <jlarkin@highlandSNIPMEtechnology.com> wrote in >>> <7qe2uh9mv99o5pt91in5j1j9b4drqqirrg@4ax.com>: >>> >>>> >>>> https://www.qorvo.com/products/p/QPD1016 >>>> >>>> The part could be very useful in wideband/pulse applications [1] but >>>> there are no DC curves, no capacitances, no Spice models, just the >>>> silly load pull cartoons. >>>> >>>> [1] except for the price of course. >>>> >>> >>> Bit puzzled by the bias on - bias off sequence for the test board... >>> page 20 pfd >>> How critical is that? >>> Needs some external circuits.. >> >> It's fiddle-biased. One needs to be careful to not blow it up. >> Envision blowing up a lot of parts on the test fixture, at $1K each. >> >> It's interesting that Id-max is 70 amps but they set the current >> limited supply to 1.1. >> >> In a real amp, presumably there would be a servo loop to sense Id and >> set the gate bias voltage, and sequence everything properly. A Spice >> model would be the way to develop that! >> >> I wonder if the gate is a diode to the source, and how that behaves. >> Presumably it is a depletion fet. Idss is of course not a measurement >> that the RF types don't understand. >> >> The EPC GaN fets are great and they have Spice models that mostly >> work. Their gate behavior is interesting. >> >> I use the SAV-5xx parts in time domain, as switches, and they have at >> least some DC curves on their data sheets; I've measured more. >> MiniCircuits promises to never offer a Spice model. >> >> "The easiest thing in the world is not to sell." >> >> - Melvin Goldstein >> > >< https://www.modelithics.com/MVP/Qorvo?comp_id=Qorvo&tab=3 > > > > >< https://www.qorvo.com/products/p/QPD1016#documents > > >< https://www.qorvo.com/products/p/QPD1016#evaluation-tools > > >cheers, Gerhard >Free trial? Do they have a Spice model? I see nonlinear RF models that need a suite of expensive RF sim stuff. I emailed them about a Spice model.
Reply by ●February 7, 20232023-02-07
On Mon, 06 Feb 2023 09:47:57 -0800, John Larkin <jlarkin@highlandSNIPMEtechnology.com> wrote:> >https://www.qorvo.com/products/p/QPD1016 > >The part could be very useful in wideband/pulse applications [1] but >there are no DC curves, no capacitances, no Spice models, just the >silly load pull cartoons. > >[1] except for the price of course.Qorvo confirms that there are no DC curves nor a Spice model.
Reply by ●February 8, 20232023-02-08
On Mon, 06 Feb 2023 09:47:57 -0800, John Larkin <jlarkin@highlandSNIPMEtechnology.com> wrote:> >https://www.qorvo.com/products/p/QPD1016 > >The part could be very useful in wideband/pulse applications [1] but >there are no DC curves, no capacitances, no Spice models, just the >silly load pull cartoons. > >[1] except for the price of course.Odd to publish surface temp rise data above 200C for a part that is epoxy-sealed. RL
Reply by ●February 8, 20232023-02-08
On Tuesday, February 7, 2023 at 7:46:18 PM UTC-8, John Larkin wrote:> On Mon, 06 Feb 2023 09:47:57 -0800, John Larkin > <jla...@highlandSNIPMEtechnology.com> wrote: > > > > >https://www.qorvo.com/products/p/QPD1016 > > > >The part could be very useful in wideband/pulse applications [1] but > >there are no DC curves, no capacitances, no Spice models, just the > >silly load pull cartoons. > > > >[1] except for the price of course. > Qorvo confirms that there are no DC curves nor a Spice model.Supposing you do manage to figure it out, chances are that Qorvo will then EOL it. lol
