I have a VCCS based on AD8130. After many googling and studying.. now I'm frustrated!
for checking the output capacitance usually I put a 1Kohm resistor on the output and check the 3-dB corner frequency. so the output capacitance is C=1/(2*pi*R*f3dB)
But I really I don't know how I should calculate the output impedance of the VCCS.