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The Signal Sped Up

DC precision considerations for high speed amplifiers, Insight #3

Michael Steffes
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Tucson_Mike
Tucson_Mike
12/5/2018 9:53:52 AM
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Blogger
Re: Good read
Hey Soufiane, 

It is not just "modern" designers that approach decomp parts with some trepidition. It has always been uphill from the first decomp part I was involved in (the CLC425) to these most recent blazing fast decomp VFA like the OPA855 (8GHz GBP). If you are tasked with a transimpedance design, most designers recognize the need for decomp and deal with it. Otherwise, it is a tough sell even with clear input noise and LSBW advantages. There are certainly added stability risks - but good models can mitigate those. Looking industrywide, I would say LTC has made a commitment to decomp (even more than I have) while Maxim recently spun out a series of decomp CMOS devices. Nice knob to use in product development if you understand the tradeoffs. 

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soufiane_ben
soufiane_ben
11/30/2018 7:26:15 PM
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Newbie
Good read
Hi Michael:

I think some designers should start by selecting the "right" process. There are compimentary processeses which lend themselves better for optimized speed/power ratios. On the other hand, most "modern" engineers seem to fear the idea of a decompenated op amp, think OP37 which is still one of the best decomp op amps ever made in my opinioon. 

I think that soon we will see increased needs for high speed and DC precision, this is particularly true for T&M and automotive but I can also see this need in medical instrumentation for instance. 

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