AD8546 'resistive load' limits

Recently I needed to specify a dual opamp with uncritical specs, for use in an oven controller:

(The other half of the amp interfaces the thermistor to the ADC, not shown.) 

A quick parametric search suggested that the AD8546 would be a good fit. Now that I'm looking closer at the data sheets prior to ordering, though, I'm seeing an unfamiliar warning:

What kind of opamp has problems driving resistive loads, and at the 100K level?!  Is this a misprint?  Nothing in the output impedance or short-circuit current specs suggests any limitations along these lines:

So I wonder if I'm missing something important here.  Any thoughts?  Obviously there are plenty of other opamps that will work in this application but before rejecting this one I'd like to learn more about the reasoning above.

Parents
  • 0
    •  Analog Employees 
    on Jun 25, 2018 12:05 PM

    Hi,

    AD8546 is a micropower opamp with 22uA maximum supply current at 18V designed and intended to be used for low power applications such as portable medical equipment and current loop drivers. Since it is low power, it is the reason it is rated to drive resistive loads down to 100kohms. Can I know what specs are important in your design?

     

     

     

     

     

     

     

Reply
  • 0
    •  Analog Employees 
    on Jun 25, 2018 12:05 PM

    Hi,

    AD8546 is a micropower opamp with 22uA maximum supply current at 18V designed and intended to be used for low power applications such as portable medical equipment and current loop drivers. Since it is low power, it is the reason it is rated to drive resistive loads down to 100kohms. Can I know what specs are important in your design?

     

     

     

     

     

     

     

Children
No Data