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From: Fred Bartoli on 13 Jan 2010 17:47 Jim Thompson a �crit : > On Wed, 13 Jan 2010 22:40:23 +0100, Fred Bartoli <" "> wrote: > >> Jim Thompson a �crit : >>> On Wed, 13 Jan 2010 14:00:23 -0700, Jim Thompson >>> <To-Email-Use-The-Envelope-Icon(a)My-Web-Site.com/Snicker> wrote: >>> >>>> On Wed, 13 Jan 2010 21:39:12 +0100, Fred Bartoli <" "> wrote: >>>> >>> [snip] >>>>> Have a look at AD8605. Just amazing. >>>>> >>> [snip] >>>> Yep. Judging from the input bias specs, they've got some HUGE input >>>> devices there. >>> [snip] >>> >>> Looked it up... L=1u W=1600u !! >>> >> Come on, you should know better... > > That's W=1.6mm, longer than most chips edge dimension. So the input > stage dominates the chip area. Not that unusual, check out... > > http://www.analog-innovations.com/SED/ICE-LM195-LM117.pdf > > The pass device takes up 2/3 of the chip. > Yup, but what I meant is that vendors' macro models almost never (read never) reflect actual devices. -- Thanks, Fred.
From: Fred Bartoli on 13 Jan 2010 17:50 John Larkin a �crit : > On Wed, 13 Jan 2010 21:39:12 +0100, Fred Bartoli <" "> wrote: > >> Jim Thompson a �crit : >>> On Wed, 13 Jan 2010 08:40:14 -0800, "Joel Koltner" >>> <zapwireDASHgroups(a)yahoo.com> wrote: >>> >>>> Did that design make it through fab, Jim, or did the company start imploding >>>> first? >>> It was fabbed at Polarfab. The company began disintegration while >>> debugging the digital was in progress. >>> >>>> I thought that combined bipolar/CMOS ("BiFET?") processes were generally >>>> considered too exotic/unnecessary-due-to-performance-improvements-in-CMOS >>>> these days? Not so? >>>> >>>> ---Joel >>> Not so for analog. Try making a low noise amplifier with only CMOS. >> Have a look at AD8605. Just amazing. >> > > Even better: > > http://focus.ti.com/docs/prod/folders/print/opa376.html > > It's 65 cents at 1K, a tad less than the ADI part. > Yep, but the sc70 package is, well, terribly huge for my needs... -- Thanks, Fred.
From: Jim Thompson on 13 Jan 2010 17:56 On Wed, 13 Jan 2010 23:47:59 +0100, Fred Bartoli <" "> wrote: >Jim Thompson a �crit : >> On Wed, 13 Jan 2010 22:40:23 +0100, Fred Bartoli <" "> wrote: >> >>> Jim Thompson a �crit : >>>> On Wed, 13 Jan 2010 14:00:23 -0700, Jim Thompson >>>> <To-Email-Use-The-Envelope-Icon(a)My-Web-Site.com/Snicker> wrote: >>>> >>>>> On Wed, 13 Jan 2010 21:39:12 +0100, Fred Bartoli <" "> wrote: >>>>> >>>> [snip] >>>>>> Have a look at AD8605. Just amazing. >>>>>> >>>> [snip] >>>>> Yep. Judging from the input bias specs, they've got some HUGE input >>>>> devices there. >>>> [snip] >>>> >>>> Looked it up... L=1u W=1600u !! >>>> >>> Come on, you should know better... >> >> That's W=1.6mm, longer than most chips edge dimension. So the input >> stage dominates the chip area. Not that unusual, check out... >> >> http://www.analog-innovations.com/SED/ICE-LM195-LM117.pdf >> >> The pass device takes up 2/3 of the chip. >> > >Yup, but what I meant is that vendors' macro models almost never (read >never) reflect actual devices. It might here, simply because they're trying to match the input noise curve. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
From: John Larkin on 13 Jan 2010 18:08 On Wed, 13 Jan 2010 23:50:49 +0100, Fred Bartoli <" "> wrote: >John Larkin a �crit : >> On Wed, 13 Jan 2010 21:39:12 +0100, Fred Bartoli <" "> wrote: >> >>> Jim Thompson a �crit : >>>> On Wed, 13 Jan 2010 08:40:14 -0800, "Joel Koltner" >>>> <zapwireDASHgroups(a)yahoo.com> wrote: >>>> >>>>> Did that design make it through fab, Jim, or did the company start imploding >>>>> first? >>>> It was fabbed at Polarfab. The company began disintegration while >>>> debugging the digital was in progress. >>>> >>>>> I thought that combined bipolar/CMOS ("BiFET?") processes were generally >>>>> considered too exotic/unnecessary-due-to-performance-improvements-in-CMOS >>>>> these days? Not so? >>>>> >>>>> ---Joel >>>> Not so for analog. Try making a low noise amplifier with only CMOS. >>> Have a look at AD8605. Just amazing. >>> >> >> Even better: >> >> http://focus.ti.com/docs/prod/folders/print/opa376.html >> >> It's 65 cents at 1K, a tad less than the ADI part. >> > >Yep, but the sc70 package is, well, terribly huge for my needs... It's available in SOT-23 and even in the huge SO-8 package. I was looking at a board the other day and noticed how big an 0805 resistor looked. That's frightening. John
From: krw on 13 Jan 2010 18:54
On Wed, 13 Jan 2010 21:39:12 +0100, Fred Bartoli <" "> wrote: >Jim Thompson a �crit : >> On Wed, 13 Jan 2010 08:40:14 -0800, "Joel Koltner" >> <zapwireDASHgroups(a)yahoo.com> wrote: >> >>> Did that design make it through fab, Jim, or did the company start imploding >>> first? >> >> It was fabbed at Polarfab. The company began disintegration while >> debugging the digital was in progress. >> >>> I thought that combined bipolar/CMOS ("BiFET?") processes were generally >>> considered too exotic/unnecessary-due-to-performance-improvements-in-CMOS >>> these days? Not so? >>> >>> ---Joel >> >> Not so for analog. Try making a low noise amplifier with only CMOS. > >Have a look at AD8605. Just amazing. We use AD8606s (dual 8605) as our go to opamp. We've started replacing them in one product with LMV852s. They're EMI hardened and do better in our 2.4GHz rich environment. > >> Try making a TVG that is stable/predictable over temperature. >> >> For quality, bipolar ROCKS ;-) >> >> ...Jim Thompson |