AD8067 single supply 24V was abnormal

HI RayW 

Can you also provide the oscilloscope result of the input signal same as the probe location on the Ltspice model?

Also, did you consider the Layout, Grounding and Bypassing Considerations on the datasheet for your board (p.16 - 17 of datasheet)? We want to make sure that there are only few variables that may contribute to this issue.

Regards,

JE

Hi,

I don't think it is abnormal. I've made a simulation for the same case that is shown on the scope. So, 24V output swing and similar time interval and duty cycle. Also, the assumed probe capacitance (C3) and bandwidth of the scope are taken into account (R4 and C2 do not load the amplifier considerably, but implements scope bandwidth of 30MHz - I guess it is close to reality). Here is the result:

It seems to me close enough to your experimental results. The slew rate specs are also met both in the simulation and in your experiment.

You've not shown your input signal. Connect it to the other channel of the scope with the same type of probe and measure simultaneously.

Zoltan

Hi

I assume RayW is pointing out that based on his simulation with 1.8V as input voltage, the expected output waveform should be also within 18V output but on the actual output on oscilloscope is about 24V. Please correct me if I am wrong with my assumption.

As you've also mentioned, we need to know the actual input voltage that he used on his circuit. I am still checking into this issue because a change from 18V to 24V output seems really strange if the actual external component values are based on the presented circuit. I will evaluate the actual circuit scenario and maybe can find out and conclude the reason for this issue.

Regards,

JE

Hi,

I believe that the questions have already been answered so I am closing this thread. Thank you!

Regards,

Mae