  For the first time the cumulative distribution function of the crossover
frequency of a contemporary operational amplifier ADA4898-2 is experimentally
studied. Using a USB Lock-In amplifier, which allows automatic frequency sweep
of the current response of a non-inverting amplifier with significant static
amplification, we measure the crossover frequency of 200 samples of ADA4898-2
operational amplifiers. This new method gives a significant advantage in
accuracy and speed of study of every operational amplifier. The theory we use
is based on the universal relation between time dependent output and input
voltages. This common relation for all operational amplifiers is applicable for
frequencies much smaller than the crossover frequency and the frequencies of
non-dominant poles. In other words, this approximation is adequate, when an
operational amplifier is included in a circuit with significant amplification.
