OPAMP single or dual? (DAC output stage)

[dougduck]

Is there any real advantage to using single opamp in the DAC output stage?
Most of the equipment i see uses dual opamp in the output stage, would this be just to save cost and board size?

 

[rayma]

Duals come in more variety, and are cheaper per op amp and pcb.
Singles can have better channel separation and layout.
Some high performance op amps are only available as single.

 

[abraxalito]

Single opamps often have compensation pins brought out, duals can't as there aren't sufficient pins on the package. So using a single may allow the opamp compensation to be optimized to a particular application.

Some high performance op amps are only available as single.

AD811 is an example of this - to my ears its the best opamp for I/V.

 

[altor]

Is there any real advantage to using single opamp in the DAC output stage?

Sometimes PCB layout is simpler with single OP.
No other advantages seen. Channel separation is not an issue, it is more than enough with dual ones.

Alex.