Hi,
Yes, you can, one caveat, make sure you load both outputs equally, also, you may have to return the I/V resistor to Vref, not ground to make sure the DAC works correctly.
Ciao T
I have a AD1853 DAC differential output current DAC. Can I check if it is okay to use only one of the current output instead of both the outputs as a single ended output DAC?
Yes, you can, one caveat, make sure you load both outputs equally, also, you may have to return the I/V resistor to Vref, not ground to make sure the DAC works correctly.
Ciao T
Hi,
Sorry, I spoke out of turn, never mind.
Ciao T
What do you mean load the output equally? How would you do that?
Sorry, I spoke out of turn, never mind.
Ciao T
oon,
I believe what Thorsten meant was to make sure to use the same impednace on both the + and - outputs of your DAC chip. If you're taking signal from the + line and it's loaded with 3k ohms for example also put 3k ohms across the - output even if you don't take any signal from there. The DAC chip will work best with equal resistance on both output phases.
I believe what Thorsten meant was to make sure to use the same impednace on both the + and - outputs of your DAC chip. If you're taking signal from the + line and it's loaded with 3k ohms for example also put 3k ohms across the - output even if you don't take any signal from there. The DAC chip will work best with equal resistance on both output phases.
Hi,
Okay, so you worked it out. When you asked "what is loading" I decided I had started something I was unwilling to finish.
Some comments, if you are going to use Op-Amp I/V anyway, use the OPA1632. It has many great advantages in such an application, like balanced inputs and outputs, so it makes a balanced I/V converter, very low noise, folded cascode singe gain stage architecture and very good output buffers. So you end up with a system having two equal but opposite polarity outputs so you can easily take a single ended output.
Otherwise, remember that an Op-Amp I/V circuits input only looks like a short at DC and very low frequencies...
If you where (for arguments sake) using tubes or maybe discrete J-Fets and wanted to avoid the balanced to se conversion, then loading both DAC outputs with identical I/V conversion RC (or whatever) combinations and using the signal from only one would be the choice, however.
I hope the above helps make your choice.
Ciao T
The chip is a single supply 5v, so the voltage at the output should be loaded to 2.5V, vref. Since the ideal load is 0ohm or input of an IV converter, I think it would be to just short it to vref..
Okay, so you worked it out. When you asked "what is loading" I decided I had started something I was unwilling to finish.
Some comments, if you are going to use Op-Amp I/V anyway, use the OPA1632. It has many great advantages in such an application, like balanced inputs and outputs, so it makes a balanced I/V converter, very low noise, folded cascode singe gain stage architecture and very good output buffers. So you end up with a system having two equal but opposite polarity outputs so you can easily take a single ended output.
Otherwise, remember that an Op-Amp I/V circuits input only looks like a short at DC and very low frequencies...
If you where (for arguments sake) using tubes or maybe discrete J-Fets and wanted to avoid the balanced to se conversion, then loading both DAC outputs with identical I/V conversion RC (or whatever) combinations and using the signal from only one would be the choice, however.
I hope the above helps make your choice.
Ciao T
Hi,
If you use this single ended, it is important to remember that it's input impedance is not zero.
Ciao T
Hey thanks for all the clarification and tips. Really appreciate it. Very likely, I will do nelson pass D1 IV stage.
If you use this single ended, it is important to remember that it's input impedance is not zero.
Ciao T
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