An ideal op amp has the following properties.
Op Amp Characteristics |
Ideal |
Real - Depends on the model |
Open Loop Gain |
Infinity |
> 100000 or 1000000 typical |
Input Impedance |
Infinity |
> 1M (Bipolar) > 1000M (FET) |
Gain Bandwidth Product |
Infinity |
1 - 20MHz |
Output Impedance |
Zero |
100 - 1000R |
Input offset voltage |
Zero |
Often Adjuatable to Zero |
The bandwidth of an op' amp' is the frequency at which the output has dropped to 70% (0.707) of the low frequency performance of the chip. (The Half Power Point).