Used operational amplifiers AD8534 and AD8532.
I just want verify your question. You want to disconnect the output of one of the op amp once it is not active? I'm seeing you have AD8534 for one of the DAC and AD8532 for the other DAC…
I can't recommend to use conventional diodes in this application.You can't achieve best performance of your circuit in this condition.
Since you are already modifying your board…
I just want verify your question. You want to disconnect the output of one of the op amp once it is not active? I'm seeing you have AD8534 for one of the DAC and AD8532 for the other DAC where these op amp outputs are connected to one load. If that is the case, I want to recommend a mux to control the output of your op amp by selecting one op amp at a time. You can check our Multiplexers here:http://www.analog.com/en/products/switches-multiplexers.html You should consider your bandwidth, voltage range requirements as well as the number of channels you needed. I also want to introduce family of op amps with disable functionality. This will eliminate the use of mux to select the op amp you want active and not. This article (Amplifier Disable Function Eliminates Need for Multiplexers in Multichannel Applications ) will be a nice read to start with. You can start with these amplifiers with disable function: ADA4895-1, ADA4897-1 or AD8041.
Please let us know if it answers your concern or you have any follow up questions.