Hi Avatar,
When operating with +15v and gnd as the supplies to the op-amp, how close to zero volts can the output drive? (load < 1mA) ?
OPA828 is not rail to rail input output (RRIO) op amp. If you are using single supply rail, your output is not going to be 0V. You have to perform level shift or AC coupling in order to get what you need.
Does operating close to the negative rail (ground) reduce the op-amp precision (drift, offset, noise) ?
These parameters should not be affected if the OPA828 is operating in a linear region. So you have to configure the bias voltage properly. For OPA828, the best bias voltage may be configured at approx. 7Vdc for 15Vdc single supply rail. This will maximize the output swing.
If you have other questions, please let us know.
Best,
Raymond
