Dear Analog Devices
I am having challenge in understanding the datasheet on the ADA4807 (alternative AD8027), in respect of the output swing.
My challenge is that I have an input from a potmeter, providing a voltage input to a “buffer”, using an opamp (ADA4841-1YRJZ) with gain +1. The voltage source to the amplifier is a filtered +5V. The signal into the amplifier is in the range of 0V to +5V, where I need the output from the opamp to be as close to the 0V to +5V as possible. Using the ADA4841, the output only rise to 4.2V. I am therefore considering to use the ADA4807 (alternative AD8027) as replacements, being able to change the component only, not needing to change the PCB layout footprint. The time and cost is crucial.
Is it possible to give me a feedback on the actual expected output swing when using a +5V power source, and an input signal of 0V to +5V?
Depending on the source impedance, i.e. the resistance of your pot, and the maximum signal and conversion frequencies (likely to be pretty low considering a pot is the source), you might not need any buffer amplifier to drive the ADC. Try a wire instead ;-).
You likely want to add some ESD protection, but that should be there no matter what.