>> Check these references, both written primarily for 
>> single-supply op amps:
>>
>> http://www.maxim-ic.com/appnotes.cfm/an_pk/1957
>> http://focus.ti.com/lit/an/slod006b/slod006b.pdf see 
>> section 17.7.3, page
>> 375 in the PDF.
>
> Looks to me like if you have a design that must be low 
> power, the best
> bet is to avoid having the uncommited op amp in the first 
> place.

Agre, but

> I assume the resistor string shouldn't be too high value, 
> two 1M resistors
> at 3V would still be 1.5uA leakage, more power draw that 
> the rest of the
> circuit might be.

Probably not if op-amp are involved. Unless you are dealing 
with ultra-special devices the supply current for opamps 
will usually be higher or much higher than that.

An exception which proves the rule is MAX406BCSA  at 1.2uA 
max supply current.

You pay for this (totally expectedly) with a 4 kHz 
gain-bandwidth product and 5 mV/uS slew rate 
(!!!!!!!!!!!!!!!!!!!!!!)
Overview

    http://www.maxim-ic.com/quick_view2.cfm/qv_pk/1468

Data sheet

        http://pdfserv.maxim-ic.com/en/ds/MAX406-MAX419.pdf



            Russell




 

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