National Semiconductor op amps can be used in many project designs.
Founded in 1959 by former employees of the Sperry Rand Corporation, National Semiconductor began developing and manufacturing silicon transistors. With 85 percent of its products purchased by the U.S. military and aerospace industry by 1961, National has enjoyed close ties and successes with its main contracts for more than five decades. Modern National products include operational amplifiers (op amps), which can be utilized in a variety of projects.
Inverting Amplifier
Op amps are differential amplifiers, or devices that amplify the difference between two inputs. Featuring both inverting and noninverting inputs, op amps can be configured as an inverting amplifier or circuit that inverts the output signal's polarity by 180 degrees in relation to the input. This project can be used to correct other signal inversion issues within another circuit or used in computer processing circuits.
Noninverting Amplifier
Op amps can be configured to amplify a signal in a noninverting fashion. The output signal of this circuit will remain in phase with the input, which will result in a clean audio signal that can be blended with the input signal without phase issues. These circuits are common in diode clipping overdrive guitar effects pedals, such as the Ibanez Tubescreamer or the Fulltone Fulldrive II. By offering large amounts of signal amplification, these op amp circuits can be used in instrument direct boxes, studio outboard effects and mixing consoles.
Lowpass Filter
Another important circuit based on National Semiconductor op amps is the Sallen-Key lowpass biquad filter. This simple circuit utilizes the feedback loop capabilities of a standard op amp to allow only low signal frequencies to pass through the circuit. Lowpass filters are a common audio circuit, found in many crossover devices to allow bass frequencies to be split to subwoofer speakers for extended bass response in home, car and professional audio applications.
Highpass Filter
The Sallen-Key circuit design can be configured to operate as a highpass filter, or circuit that allows only high signal frequencies to pass through. This design is similar in construction to the lowpass filter circuit, but filters signals in an opposite manner. These types of circuits are frequently used in audio devices such as microphone preamps, instrument direct boxes and mixing consoles to remove unnecessary bass frequencies from vocals and guitars.
Tags: National Semiconductor, Amplifier amps, amps configured, bass frequencies, circuit that
