Because a practical op-amp is not “ideal”, when searching for the right op-amp for an application, various performance specifications need to be taken into consideration. We will use op-amp datasheets to describe the DC, and AC specifications of op-amps.
The picture above is an example of an op-amp datasheet. Electrical characteristics are measurable electrical properties of a device inherent in it's design. They are used to predict the performance of the device as an element of an electrical circuit. The measurements that appear in the electrical characteristics tables are based on the device being operated within the operating conditions. The operating conditions have a similarity to maximum ratings in that operation outside the stated limits could cause unsatisfactory performance. The operating conditions, however, do not carry the implication of device damage if they are exceeded.
Modern op-amps are housed in small semiconductor packages, such as TSSOP, SOIC, PDIP, and SOT. Below are some examples of various MCP601 packages.
| 8-pin PDIP | 8-pin SOIC | 8-pin TSSOP | 5-pin SOT-23 |
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| Length (D): ~ 9.1 mm Width (E): ~ 7.8 mm |
Length (D): ~ 4.9 mm Width (E): ~ 6.0 mm |
Length (D): ~ 3.0 mm Width (E): ~ 6.4 mm |
Length (D): ~ 3.0 mm Width (E): ~ 2.7 mm |