ECL logic SPICE models
in [Design]
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From: John Larkin on 11 Sep 2009 18:18 On Fri, 11 Sep 2009 11:06:55 -0700, Joerg <invalid(a)invalid.invalid> wrote: >John Larkin wrote: >> On Fri, 11 Sep 2009 08:59:24 -0700, Joerg <invalid(a)invalid.invalid> >> wrote: >> >>> John Larkin wrote: >>>> On Fri, 11 Sep 2009 08:38:08 -0700, Joerg <invalid(a)invalid.invalid> >>>> wrote: >>>> >>>>> John Larkin wrote: >>>>>> On Thu, 10 Sep 2009 09:39:45 -0700, Joerg <invalid(a)invalid.invalid> >>>>>> wrote: >>>>>> >>>>>>> Jim Thompson wrote: >>>>>>>> On Thu, 10 Sep 2009 09:25:08 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> Jim Thompson wrote: >>>>>>>>>> On Wed, 09 Sep 2009 17:09:13 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> Gentlemen, >>>>>>>>>>> >>>>>>>>>>> Does anyone know of a source for SPICE models of ECL gates? >>>>>>>>>>> Unfortunately ON Semi only supplies IBIS models :-( >>>>>>>>>>> >>>>>>>>>>> I know, I know, much of this will fall under trade secrets or NDAs and >>>>>>>>>>> can't be shared. Just wondering why some companies seem reluctant to >>>>>>>>>>> share this stuff. Makes no sense since providing models can only boost >>>>>>>>>>> sales. No, not the models some of you might think about ... :-) >>>>>>>>>>> >>>>>>>>>>> Alternatively, is there a recipe about how to boil one out of an IBIS >>>>>>>>>>> model file? >>>>>>>>>> IBIS models only model the package. >>>>>>>>>> >>>>>>>>>> I have the Spice models... I designed much of it... I can't share it >>>>>>>>>> ;-) >>>>>>>>>> >>>>>>>>> Dang, I thought so :-( >>>>>>>> What is it you're trying to model? >>>>>>>> >>>>>>> Mostly linear behavior and change of prop delays with chip temperature. >>>>>>> But it's nothing for a project (yet), just kicking the tires. The newer >>>>>>> 8GHz stuff looks very enticing but when I saw the prices I almost >>>>>>> dropped my coffee cup. >>>>>> Heck, the Onsemi GigaComm stuff is only about $35 a gate. ... >>>>> Only? ... :-) >>>>> >>>>> Problem is, with many of my designs the whole solution including burden >>>>> (assembly, additional rigging costs, etc.) has to be lower than that. >>>> The only way you're going to get a heap of 5 GHz logic for $10 is to >>>> spin a custom IC and make tens of millions of them. $35 for a gate or >>>> a flipflop is OK if you're building a $5000 piece of test equipment. >>>> >>>> 8-port gigabit ethernet switches are in the $60 retail range now, and >>>> will surely be a lot cheaper soon. That's an amazing heap of fast >>>> logic. A single 10 MBPS ethernet interface used to cost as much as a >>>> nice new car. >>>> >>> Ok, large scale integrated stuff is a different game. But when $30 are >>> charged for a single inverter I'll do it with a few BFP620 transistors. >>> ft around 65GHz, SOT23, about 50 cents in qties :-) >> >> I haven't had much luck doing picosecond-speed time-domain stuff with >> discrete bipolars. A 65 GHz SiGe transistor has a beta of 10 at 6 GHz, >> dropping at higher currents, and turns out to be a pretty pokey switch >> in real life. Package parasitics tend to make it an oscillator if you >> try to really use the speed potential. The narrowband RF boys can tune >> the parasitics out, but wideband is different. >> > >So far bipolars have been good to me, starting with the old BFS17 in the >80's. To this day I always keep a vial full of those on hand. Then >faster and faster ones showed up. Only problem is that most are from >large European companies and their sales channels are often, ahem, let's >say sub-par. > >Take a look at some broadband stuff such as CATV amps. Many are done >with discrete BJT, most likely for cost and 2nd-sourcing reasons. But >yes, parasitics can get you and the layout is not at all trivial. > > >> I have had good luck using discrete phemts as switches, but they're >> more like $1 or so. >> > >That I still have to try. > > >> If you can tolerate 1-2 ns prop delays and 600 ps edges, some of the >> cmos TinyLogic parts are great, and in your price range. >> > >That's sometimes an order of magnitude too slow :-( Some of the cheapest gain-bandwidth around is in darlington MMICS. You can get 4-8 GHz of stable, 20 dB-ish gain for under a buck. They work fine in pulse apps, too. John
From: Joerg on 11 Sep 2009 18:33 John Larkin wrote: > On Fri, 11 Sep 2009 11:06:55 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > >> John Larkin wrote: >>> On Fri, 11 Sep 2009 08:59:24 -0700, Joerg <invalid(a)invalid.invalid> >>> wrote: [...] >>>> Ok, large scale integrated stuff is a different game. But when $30 are >>>> charged for a single inverter I'll do it with a few BFP620 transistors. >>>> ft around 65GHz, SOT23, about 50 cents in qties :-) >>> I haven't had much luck doing picosecond-speed time-domain stuff with >>> discrete bipolars. A 65 GHz SiGe transistor has a beta of 10 at 6 GHz, >>> dropping at higher currents, and turns out to be a pretty pokey switch >>> in real life. Package parasitics tend to make it an oscillator if you >>> try to really use the speed potential. The narrowband RF boys can tune >>> the parasitics out, but wideband is different. >>> >> So far bipolars have been good to me, starting with the old BFS17 in the >> 80's. To this day I always keep a vial full of those on hand. Then >> faster and faster ones showed up. Only problem is that most are from >> large European companies and their sales channels are often, ahem, let's >> say sub-par. >> >> Take a look at some broadband stuff such as CATV amps. Many are done >> with discrete BJT, most likely for cost and 2nd-sourcing reasons. But >> yes, parasitics can get you and the layout is not at all trivial. >> >> >>> I have had good luck using discrete phemts as switches, but they're >>> more like $1 or so. >>> >> That I still have to try. >> >> >>> If you can tolerate 1-2 ns prop delays and 600 ps edges, some of the >>> cmos TinyLogic parts are great, and in your price range. >>> >> That's sometimes an order of magnitude too slow :-( > > Some of the cheapest gain-bandwidth around is in darlington MMICS. You > can get 4-8 GHz of stable, 20 dB-ish gain for under a buck. They work > fine in pulse apps, too. > 8GHz/20dB for under a buck? That would be my kind of device. Have a particular one in mind? One issue I found with RF devices was that you can sometimes only obtain small signal simulator models that aren't very helpful with pulse apps, plus require software that costs more than your Volkswagen. Even with big LDMOS parts I had that happen. One company (PolyFet) stuck out and provided SPICE models. So the big competitor will be left out ... sorry, NXP. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: John Larkin on 11 Sep 2009 19:09 On Fri, 11 Sep 2009 15:33:08 -0700, Joerg <invalid(a)invalid.invalid> wrote: >John Larkin wrote: >> On Fri, 11 Sep 2009 11:06:55 -0700, Joerg <invalid(a)invalid.invalid> >> wrote: >> >>> John Larkin wrote: >>>> On Fri, 11 Sep 2009 08:59:24 -0700, Joerg <invalid(a)invalid.invalid> >>>> wrote: > >[...] > >>>>> Ok, large scale integrated stuff is a different game. But when $30 are >>>>> charged for a single inverter I'll do it with a few BFP620 transistors. >>>>> ft around 65GHz, SOT23, about 50 cents in qties :-) >>>> I haven't had much luck doing picosecond-speed time-domain stuff with >>>> discrete bipolars. A 65 GHz SiGe transistor has a beta of 10 at 6 GHz, >>>> dropping at higher currents, and turns out to be a pretty pokey switch >>>> in real life. Package parasitics tend to make it an oscillator if you >>>> try to really use the speed potential. The narrowband RF boys can tune >>>> the parasitics out, but wideband is different. >>>> >>> So far bipolars have been good to me, starting with the old BFS17 in the >>> 80's. To this day I always keep a vial full of those on hand. Then >>> faster and faster ones showed up. Only problem is that most are from >>> large European companies and their sales channels are often, ahem, let's >>> say sub-par. >>> >>> Take a look at some broadband stuff such as CATV amps. Many are done >>> with discrete BJT, most likely for cost and 2nd-sourcing reasons. But >>> yes, parasitics can get you and the layout is not at all trivial. >>> >>> >>>> I have had good luck using discrete phemts as switches, but they're >>>> more like $1 or so. >>>> >>> That I still have to try. >>> >>> >>>> If you can tolerate 1-2 ns prop delays and 600 ps edges, some of the >>>> cmos TinyLogic parts are great, and in your price range. >>>> >>> That's sometimes an order of magnitude too slow :-( >> >> Some of the cheapest gain-bandwidth around is in darlington MMICS. You >> can get 4-8 GHz of stable, 20 dB-ish gain for under a buck. They work >> fine in pulse apps, too. >> > >8GHz/20dB for under a buck? That would be my kind of device. Have a >particular one in mind? There are tons, like http://www.minicircuits.com/products/amplifiers_monolithic.html#lee http://products.rfmd.com/productselector.jsp?select_family=Amplifiers%20%28BB%20and%20General%29 http://www.triquint.com/prodserv/more_info/download.aspx?file=/docs/Datasheets/E/ECG003.pdf Some of the SOT-89 devices are really interesting. > >One issue I found with RF devices was that you can sometimes only obtain >small signal simulator models that aren't very helpful with pulse apps, >plus require software that costs more than your Volkswagen. Even with >big LDMOS parts I had that happen. One company (PolyFet) stuck out and >provided SPICE models. So the big competitor will be left out ... sorry, >NXP. I don't simulate this stuff, I test. Most microwave parts are characterized small-signal, S-params. Spice models are very rare in this business. I know things about some of these parts that the manufacturers don't know. John
From: Joerg on 11 Sep 2009 19:38 John Larkin wrote: > On Fri, 11 Sep 2009 15:33:08 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > >> John Larkin wrote: >>> On Fri, 11 Sep 2009 11:06:55 -0700, Joerg <invalid(a)invalid.invalid> >>> wrote: >>> >>>> John Larkin wrote: >>>>> On Fri, 11 Sep 2009 08:59:24 -0700, Joerg <invalid(a)invalid.invalid> >>>>> wrote: >> [...] >> >>>>>> Ok, large scale integrated stuff is a different game. But when $30 are >>>>>> charged for a single inverter I'll do it with a few BFP620 transistors. >>>>>> ft around 65GHz, SOT23, about 50 cents in qties :-) >>>>> I haven't had much luck doing picosecond-speed time-domain stuff with >>>>> discrete bipolars. A 65 GHz SiGe transistor has a beta of 10 at 6 GHz, >>>>> dropping at higher currents, and turns out to be a pretty pokey switch >>>>> in real life. Package parasitics tend to make it an oscillator if you >>>>> try to really use the speed potential. The narrowband RF boys can tune >>>>> the parasitics out, but wideband is different. >>>>> >>>> So far bipolars have been good to me, starting with the old BFS17 in the >>>> 80's. To this day I always keep a vial full of those on hand. Then >>>> faster and faster ones showed up. Only problem is that most are from >>>> large European companies and their sales channels are often, ahem, let's >>>> say sub-par. >>>> >>>> Take a look at some broadband stuff such as CATV amps. Many are done >>>> with discrete BJT, most likely for cost and 2nd-sourcing reasons. But >>>> yes, parasitics can get you and the layout is not at all trivial. >>>> >>>> >>>>> I have had good luck using discrete phemts as switches, but they're >>>>> more like $1 or so. >>>>> >>>> That I still have to try. >>>> >>>> >>>>> If you can tolerate 1-2 ns prop delays and 600 ps edges, some of the >>>>> cmos TinyLogic parts are great, and in your price range. >>>>> >>>> That's sometimes an order of magnitude too slow :-( >>> Some of the cheapest gain-bandwidth around is in darlington MMICS. You >>> can get 4-8 GHz of stable, 20 dB-ish gain for under a buck. They work >>> fine in pulse apps, too. >>> >> 8GHz/20dB for under a buck? That would be my kind of device. Have a >> particular one in mind? > > > There are tons, like > > http://www.minicircuits.com/products/amplifiers_monolithic.html#lee > > http://products.rfmd.com/productselector.jsp?select_family=Amplifiers%20%28BB%20and%20General%29 > > http://www.triquint.com/prodserv/more_info/download.aspx?file=/docs/Datasheets/E/ECG003.pdf > > Some of the SOT-89 devices are really interesting. > Those are cool. However, the ECG003 is over three bucks although the datasheet looks great. >> One issue I found with RF devices was that you can sometimes only obtain >> small signal simulator models that aren't very helpful with pulse apps, >> plus require software that costs more than your Volkswagen. Even with >> big LDMOS parts I had that happen. One company (PolyFet) stuck out and >> provided SPICE models. So the big competitor will be left out ... sorry, >> NXP. > > I don't simulate this stuff, I test. Most microwave parts are > characterized small-signal, S-params. Spice models are very rare in > this business. I know things about some of these parts that the > manufacturers don't know. > Lately I have simulated more, and then straight to layout. The one that's in fab right now is a white-knuckle ride because I am using a device in a weird way. Usually pans out though. What often amazes me is how close to abs max people (and sometimes app notes) bias RF devices. When it says 7V they bias them to 5V or 6V on the collector/drain. Some day a huge pulse finds its way into the input, almost saturates the device, then it lets go, the inductor shoots up ... phut. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: John Larkin on 11 Sep 2009 22:05
On Fri, 11 Sep 2009 16:38:42 -0700, Joerg <invalid(a)invalid.invalid> wrote: >John Larkin wrote: >> On Fri, 11 Sep 2009 15:33:08 -0700, Joerg <invalid(a)invalid.invalid> >> wrote: >> >>> John Larkin wrote: >>>> On Fri, 11 Sep 2009 11:06:55 -0700, Joerg <invalid(a)invalid.invalid> >>>> wrote: >>>> >>>>> John Larkin wrote: >>>>>> On Fri, 11 Sep 2009 08:59:24 -0700, Joerg <invalid(a)invalid.invalid> >>>>>> wrote: >>> [...] >>> >>>>>>> Ok, large scale integrated stuff is a different game. But when $30 are >>>>>>> charged for a single inverter I'll do it with a few BFP620 transistors. >>>>>>> ft around 65GHz, SOT23, about 50 cents in qties :-) >>>>>> I haven't had much luck doing picosecond-speed time-domain stuff with >>>>>> discrete bipolars. A 65 GHz SiGe transistor has a beta of 10 at 6 GHz, >>>>>> dropping at higher currents, and turns out to be a pretty pokey switch >>>>>> in real life. Package parasitics tend to make it an oscillator if you >>>>>> try to really use the speed potential. The narrowband RF boys can tune >>>>>> the parasitics out, but wideband is different. >>>>>> >>>>> So far bipolars have been good to me, starting with the old BFS17 in the >>>>> 80's. To this day I always keep a vial full of those on hand. Then >>>>> faster and faster ones showed up. Only problem is that most are from >>>>> large European companies and their sales channels are often, ahem, let's >>>>> say sub-par. >>>>> >>>>> Take a look at some broadband stuff such as CATV amps. Many are done >>>>> with discrete BJT, most likely for cost and 2nd-sourcing reasons. But >>>>> yes, parasitics can get you and the layout is not at all trivial. >>>>> >>>>> >>>>>> I have had good luck using discrete phemts as switches, but they're >>>>>> more like $1 or so. >>>>>> >>>>> That I still have to try. >>>>> >>>>> >>>>>> If you can tolerate 1-2 ns prop delays and 600 ps edges, some of the >>>>>> cmos TinyLogic parts are great, and in your price range. >>>>>> >>>>> That's sometimes an order of magnitude too slow :-( >>>> Some of the cheapest gain-bandwidth around is in darlington MMICS. You >>>> can get 4-8 GHz of stable, 20 dB-ish gain for under a buck. They work >>>> fine in pulse apps, too. >>>> >>> 8GHz/20dB for under a buck? That would be my kind of device. Have a >>> particular one in mind? >> >> >> There are tons, like >> >> http://www.minicircuits.com/products/amplifiers_monolithic.html#lee >> >> http://products.rfmd.com/productselector.jsp?select_family=Amplifiers%20%28BB%20and%20General%29 >> >> http://www.triquint.com/prodserv/more_info/download.aspx?file=/docs/Datasheets/E/ECG003.pdf >> >> Some of the SOT-89 devices are really interesting. >> > >Those are cool. However, the ECG003 is over three bucks although the >datasheet looks great. > > >>> One issue I found with RF devices was that you can sometimes only obtain >>> small signal simulator models that aren't very helpful with pulse apps, >>> plus require software that costs more than your Volkswagen. Even with >>> big LDMOS parts I had that happen. One company (PolyFet) stuck out and >>> provided SPICE models. So the big competitor will be left out ... sorry, >>> NXP. >> >> I don't simulate this stuff, I test. Most microwave parts are >> characterized small-signal, S-params. Spice models are very rare in >> this business. I know things about some of these parts that the >> manufacturers don't know. >> > >Lately I have simulated more, and then straight to layout. The one >that's in fab right now is a white-knuckle ride because I am using a >device in a weird way. Usually pans out though. > >What often amazes me is how close to abs max people (and sometimes app >notes) bias RF devices. When it says 7V they bias them to 5V or 6V on >the collector/drain. Some day a huge pulse finds its way into the input, >almost saturates the device, then it lets go, the inductor shoots up ... >phut. I've run 7-volt-rated MESfets at 18 volts, and 2 volt RF schottkies at 6. I sometimes test parts to destruction and then back off some. The performance is often worth the small risk. Lots of RF devices seem to have voltage ratings that assume an RF tank in the output, so that the actual instantaneous drain excursion is 0 to twice Vcc. The RF guys are really, really terrible when it comes to realtime specs. You're lucky to get any DC curves. More often there's an app circuit with an input match, an output match, and a gate bias trimpot. John |