On Fri, 27 Oct 2023 08:04:35 -0400, legg <legg@nospam.magma.ca> wrote:>On Thu, 26 Oct 2023 10:19:50 -0700, john larkin <jl@650pot.com> wrote: > >>https://www.minicircuits.com/WebStore/dashboard.html?model=TAV1-541NM%2B&utm_campaign=Product%20Focus%20Emails%202023%20%26%20Onward&utm_medium=email&_hsmi=279821766&_hsenc=p2ANqtz-9MbcHJHjYg6_2uzVDHSL13EsHrk1Q6ZhSHQEwOQSif6Y1l55GNDwI_YEWiJGP8nVJdlmIf1bwj6kW8ZaQVj8XtIGwlLgVa4tPz5ednrtuuRQiRkNY&utm_content=279665588&utm_source=hs_email >> >>MiniCircuits calls these both MMICs and Transistors, but they sure >>look like bare transistors. >> >>The 45 MHz lower frequency limit is strange. >> >>THey do have DC curves, which is refreshing in an RF part. >> >>Rds-on, seldom specified for an RF part, looks like about 5 ohms. >> >>I wish they had Spice models. > > >Package size and pinout is roughly equivalent to HP 'minipak' >used for HMPP-3890/92/95. > >RLPIN diodes. Interestingly also specified to 6 GHz max. The phemt has a funny round 5th pin of unknown function. I've tried using PIN diodes in time domain with expensively bad results. Some RF parts are usable in time domain, some aren't. The RF boys just ignore that market.
more phemts
Started by ●October 26, 2023
Reply by ●October 27, 20232023-10-27
Reply by ●October 29, 20232023-10-29
On 2023-10-26 13:19, john larkin wrote:> https://www.minicircuits.com/WebStore/dashboard.html?model=TAV1-541NM%2B&utm_campaign=Product%20Focus%20Emails%202023%20%26%20Onward&utm_medium=email&_hsmi=279821766&_hsenc=p2ANqtz-9MbcHJHjYg6_2uzVDHSL13EsHrk1Q6ZhSHQEwOQSif6Y1l55GNDwI_YEWiJGP8nVJdlmIf1bwj6kW8ZaQVj8XtIGwlLgVa4tPz5ednrtuuRQiRkNY&utm_content=279665588&utm_source=hs_email > > MiniCircuits calls these both MMICs and Transistors, but they sure > look like bare transistors. > > The 45 MHz lower frequency limit is strange. > > THey do have DC curves, which is refreshing in an RF part. > > Rds-on, seldom specified for an RF part, looks like about 5 ohms. > > I wish they had Spice models. >Those are the same as the SAV series, but in a different package. The $70 sample kit has both kinds. 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
Reply by ●October 29, 20232023-10-29
On 2023-10-26 18:54, Joe Gwinn wrote:> On Fri, 27 Oct 2023 01:19:18 +0300, Dimiter_Popoff <dp@tgi-sci.com> > wrote: > >> On 10/26/2023 23:13, john larkin wrote: >>> On 26 Oct 2023 19:54:19 GMT, Uwe Bonnes >>> <bon@hertz.ikp.physik.tu-darmstadt.de> wrote: >>> >>>> john larkin <jl@650pot.com> wrote: >>>>> https://www.minicircuits.com/WebStore/dashboard.html?model=TAV1-541NM%2B&utm_campaign=Product%20Focus%20Emails%202023%20%26%20Onward&utm_medium=email&_hsmi=279821766&_hsenc=p2ANqtz-9MbcHJHjYg6_2uzVDHSL13EsHrk1Q6ZhSHQEwOQSif6Y1l55GNDwI_YEWiJGP8nVJdlmIf1bwj6kW8ZaQVj8XtIGwlLgVa4tPz5ednrtuuRQiRkNY&utm_content=279665588&utm_source=hs_email >>>>> >>>>> MiniCircuits calls these both MMICs and Transistors, but they sure >>>>> look like bare transistors. >>>>> >>>>> The 45 MHz lower frequency limit is strange. >>>>> >>>>> THey do have DC curves, which is refreshing in an RF part. >>>>> >>>>> Rds-on, seldom specified for an RF part, looks like about 5 ohms. >>>>> >>>>> I wish they had Spice models. >>>>> >>>> >>>> I do not find the DC curves in the datasheet. Can you give a hint? >>> >>> Data sheet page 3. That suggets operation down to DC. >>> >>> The 45 MHz might be caused by coupling caps on the eval board or >>> something. I want to use parts like these as switches. >>> >>> Some MMICs have internal bias circuits that indeed wreck the low >>> frequency response. >>> >> >> They do look interesting as switches indeed. >> Are they JFET-s? That gate-source +0.7V max and the max gate >> current suggest sort of that, although 0.7 looks too high. >> I have biased (during wrestling this or that, not in an end >> product IIRC) JFETS slightly above 0 G-S to get even less >> channel resistance but they must have brought that to a >> new level somehow. > > They are not JFETS. MiniCircuits has a good summary. > > .<https://blog.minicircuits.com/mmic-technologies-pseudomorphic-high-electron-mobility-transistor-phemt/> > > People have observed that pHEMTs seem to have relatively low flicker > noise for a GHz amplifier. My guess is that this is because very > clean materials and processes are needed to make a pHEMT. > > Joe Gwinn >The ones I've measured have 1/f corners of 10-50 MHz. With a flatband noise of 0.3 nV in 1 Hz, that gets you about 1-nV noise at 1 MHz, not awful at all. They're great for bootstraps, as long as you bootstrap their drains as well--otherwise they make very disappointing followers. 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
Reply by ●October 29, 20232023-10-29
On Sun, 29 Oct 2023 09:19:28 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:>On 2023-10-26 13:19, john larkin wrote: >> https://www.minicircuits.com/WebStore/dashboard.html?model=TAV1-541NM%2B&utm_campaign=Product%20Focus%20Emails%202023%20%26%20Onward&utm_medium=email&_hsmi=279821766&_hsenc=p2ANqtz-9MbcHJHjYg6_2uzVDHSL13EsHrk1Q6ZhSHQEwOQSif6Y1l55GNDwI_YEWiJGP8nVJdlmIf1bwj6kW8ZaQVj8XtIGwlLgVa4tPz5ednrtuuRQiRkNY&utm_content=279665588&utm_source=hs_email >> >> MiniCircuits calls these both MMICs and Transistors, but they sure >> look like bare transistors. >> >> The 45 MHz lower frequency limit is strange. >> >> THey do have DC curves, which is refreshing in an RF part. >> >> Rds-on, seldom specified for an RF part, looks like about 5 ohms. >> >> I wish they had Spice models. >> > >Those are the same as the SAV series, but in a different package. The >$70 sample kit has both kinds. > >Cheers > >Phil HobbsGood news. It sounds like these parts are popular enough to add new packages, which suggests they may be available for a while. Several other sources of phemts have discontinued them. Less inductance is good. https://www.dropbox.com/s/qttp09vpw3kcee3/SAV541_Xray.jpg?raw=1 We have a new xray machine that can resolve wirebonds. I'll get some pics of the new versions, the entire sample kit.
Reply by ●November 12, 20232023-11-12
