Hi, I have a question about using AD8561 for 100kHz or higher frequency Sine to Square Wave Conversion.
The comparator I'm using is AD8561 and the circuit diagram I set up on breadboard is
And the response I get is as follows, with sine wave as input and blue as pin7 output.
Is there a way to get rid of these ripple/oscillation and get 7ns response bandwidth?
Thank you Harry for your reply. I apologize that the pictures didn't show up. I attached the pictures again here.
I did bypass the supplies.
Hi, Harry, I got weird looking signals.
I tried out using 10 or 20ohm resistors.
The diagram of the circuit I test is
The response is:
One can see that even the input signal is distorted at the zero crossing.
Also I don't understand why the logic "0" looks so weird below 0V.
The package I'm using is 8-DIP, the picture on the top right in the manual (http://d0server1.fnal.gov/projects/SMT_teststand/documents/Interface_card%5CData-Sheets%5CAD8561_0-AD.pdf)
I verified that the PIN4 -V is -5V. In that regard, I do get confused why output does not go to negative. Am I setting the latch voltage wrong? I don't need latch, so I grounded the latch pin (PIN5) as well the ground pin (PIN 6).
I'm using an Agilent function generator as signal source to 10 or 20 ohm resistor connected to +IN of AD8561.
In 5.PNG, the yellow is input signal. There's a kink at zero crossing after the signal is connected to input resistor. The signal is smooth if it's only detected using oscillascope. Magenta is PIN7 output and blue is PIN4 -V.
In 7.PNG, the blue is PIN8, the inverted output of output PIN7,
In 9.PNG, I reduce the signal amplitude to 1.3V. The bulge in OFF state is gone. It's flat. Is the OFF state supposed to go to -5V is I connect the -V to -5V? I'm using breadboard at this moment, but there's little current flowing so it shouldn't cause such distortion on signal, should it?
Thank you very much.