SV: Re: [sdiy] LF357 as follower / departure from ideal opamp behaviour

[Ian Fritz]

At 02:43 PM 2/15/06, synth1 at airmail.net wrote:
>[Leans over, looks at calander, whispers....]
>
>Psssttt! It's *2006*, Ian :)
>
>Paul S.
>loves the modern op amp

Yabbit --

CA3140:
a) still in production
b) MOSFET input with measured (by me) input bias under 1 pA (Rin speced at 
1.5 TOhm)
c) costs $.45

Whereas -- AD821
a) no such thing
b) AD822:
    1) JFET input with input bias up to 25 pA
    2) costs $8.20

Ian
loves hi Z
loves cheap