Op Amp Limitations

Unfortunately Op Amps are not as perfect as we thought....
There is a slight modification to the "Golden Rules"
1) The op amp will "try" to keep the voltage difference between the terminals equal to a small offset voltage.
2) The op amp will only sink a very small input bias current. (~3pA)

Let's test out some limitations!
Lab 9-1:  Slew Rate -
With a 1kHz square wave, I measured a rising slew rate of  11.5 V/microsecond,
and a falling slew rate of 13.6 V/mircosecond.
The rates were the same for waves from 100kHz - 10Hz

With a 2V sine wave, I surfed frequencies until I found where the output amplitude begins to drop (see pic below), this was 1.5MHz.   At 1.5MHz, a cycle will last 0.667 microseconds, which means the amp has 0.333 microseconds to rise from -2V to +2V.  With the slew rate I found above (11.5), the amp could only rise ~ 3.83 Volts in time. It makes sense that this frequency is were the amplitude begin to be limited.

Horizontal Lines show what V should be