LM12CL National Semiconductor, LM12CL Datasheet - Page 4

• Manufacturer Part Number: LM12CL
• Description: 80W Operational Amplifier
• Manufacturer: National Semiconductor

www.national.com
Typical Performance Characteristics
Frequency Response
Input Bias Current
Supply Current
Application Information
GENERAL
Twenty five years ago the operational amplifier was a spe-
cialized design tool used primarily for analog computation.
However, the availability of low cost IC op amps in the late
1960’s prompted their use in rather mundane applications,
replacing a few discrete components. Once a few basic prin-
ciples are mastered, op amps can be used to give exception-
ally good results in a wide range of applications while mini-
mizing both cost and design effort.
The availability of a monolithic power op amp now promises
to extend these advantages to high-power designs. Some
conventional applications are given here to illustrate op amp
design principles as they relate to power circuitry. The inevi-
table fall in prices, as the economies of volume production
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Output Impedance
Input Noise Voltage
Supply Current
(Continued)
4
are realized, will prompt their use in applications that might
now seem trivial. Replacing single power transistors with an
op amp will become economical because of improved per-
formance, simplification of attendant circuitry, vastly im-
proved fault protection, greater reliability and the reduction of
design time.
Power op amps introduce new factors into the design equa-
tion. With current transients above 10A, both the inductance
and resistance of wire interconnects become important in a
number of ways. Further, power ratings are a crucial factor in
determining performance. But the power capability of the IC
cannot be realized unless it is properly mounted to an ad-
equate heat sink. Thus, thermal design is of major impor-
tance with power op amps.
This application summary starts off by identifying the origin
of strange problems observed while using the LM12 in a
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Power Supply Rejection
Common Mode Rejection
Cross-Supply Current
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