Operational Amplifiers Questions

• An op-amp has very low open-loop gain.
• This circuit is a differentiator.
• A 555 timer can be configured as an astable multivibrator.
• Operational amplifiers (op-amps) use internal capacitive coupling between stages.
• The TO-5 operational amplifier package can have 5 pins.
• This circuit is operating in a closed-loop mode.
• The voltage-follower amplifier circuit has a fixed voltage gain of approximately 10.
• If the frequency of an astable multivibrator is 54.86 kHz then its period is 1.82 s.
• This circuit is a voltage follower.
• An operational amplifier contains a differential amplifier, a voltage amplifier, and an output amplifier.
• Changing the input voltage to an op-amp circuit will change its voltage gain.
• A virtual ground is a ground for current, but not for voltage.
• Current actually flows into or out of a virtual ground.
• An open feedback resistor in an inverting or noninverting op-amp circuit can cause severe clipping of the output signal.
• An S-R flip-flop is an example of a bistable multivibrator circuit.
• The frequency of a crystal is dependent on how much voltage is applied to activate it.
• If the two inputs to a differential amplifier are exactly the same, then the output is the signal multiplied by two.
• If an input signal is applied to the inverting input of an op-amp with the noninverting input grounded, the output signal would be opposite in polarity with the input.
• A monostable multivibrator must be triggered.
• The difference between the upper and lower trigger points is called the Schmitt trigger.