[sdiy] Noninverting precision half-wave rectifier?

[Ian Fritz]

At 11:59 PM 9/25/2009, David G. Dixon wrote:
>Most of you are probably aware of the inverting precision half-wave
>rectifier (inverting opamp with two artfully placed diodes).  Well, I'm
>looking this old book "Handbook of Operational Amplifier Circuit Design",
>and it's also got a schematic of a NON-inverting precision half-wave
>rectifier (Fig. 16.6 on page 16-6).  It is basically the non-inverting
>analogue of the inverting rectifier.  I'm thinking, "Wow, this is great: an
>active rectifier with high input impedance which isn't severely slew-rate
>limited.  Why haven't the other books mentioned this great circuit?!?"
>However, when I simulate it in Multisim, it doesn't rectify.


You might want to look at W. Jung's opamp book.  It shows several designs 
along with detailed evaluations of their pros and cons.

Ian