When injected a pulse to our circuit, the pulse amplitude dropped a lot

We are using an AFG31000. We try to inject a pulse with 3.3 Vpp. We checked the pulse with an oscilloscope. But when we output the signal to a circuit. Its amplitude dropped to less than 1 Vpp. We tried to set load to highZ. Setting it to 50 Ohm didn't work, either. Is there any setting I should do? Please help me. Thanks!

Hi Carrie,

How fast is your pulse and what's the bandwidth of your oscilloscope?
An image of what you see on the oscilloscope would also be useful.

Hi Teles,

The pulse is 100 Hz, but I set it to burst mode with only one cycle, and trigger inter interval 60 s. I want ti get a single pulse. The oscilloscope is tektronix MDO34 200 MHz.

Hi Carrie,

This sounds very similar to the thread you made a month ago.

As discussed there, the problem is likely your circuit which is loading down your signal. Do you know the impedance of your circuit?

Hi Teles,

It's high impedance. But I have set the load of function generator HighZ. There is a micro controller in the circuit. Is it the cause? How can I do with it?
 

Hi Carrie,

How high impedance are you talking? How does this evolve with frequency?

You can have a circuit that is very high impedance at DC but at high frequencies presents low impedance, which would explain the problem you're seeing.

If your circuit has low impedance then what you can try to do is characterize it and then adjust the AFG amplitude accordingly.