Pos. fbk. Op. Amp. - (spice) noise

see also : Dif. Pos.-fbk. op.-Amp.

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about LM324 , uA741 , TL071 , LM308 :

  compared to conventional biasing schemes : 

the pos.-fbk scheme has more poor noise and frequency characteristics but it enables to use the feedback shoulder to excite a crystal or reduce the input current . . .

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 [Eop]

High noise immunity logic - Update 3

Made some simple comparative "pickup" tests

with the speed --or-- supply range improved variants

. . . and with the original --and-- the biasing adjusted orig.

so far the latest version (A5►Q5) is the least sensitive to (order from most to least susceptible noise source = the INP noise affects the circuit operation the most . . . and the GND noise the least)

• noise from inp
• noise from +power rail
• noise from –power rail

PS! -- don't ignore the switch "so far" -- there is always a test that your equipment will fail at (we just haven't spotted such yet . . . )

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[Eop]

a noise amp test turns out to be a resolute op-amp models' quality checker !!!

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versus

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with one exception ???

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