Op Amp LM741
The LM741 is a general-purpose operational amplifier It offers many features which make its application nearly foolproof: overload protection on the input and output, no latch-up when the common- mode range is exceeded, as well as freedom from oscillations.
It is intended for a wide range of analog applications. The high gain and wide range of operating voltage provide superior performance in integrator, summing amplifier, and general feedback applications. The LM741 can operate with a single or dual power supply voltage.
Open-Loop Amplifier
The LM741 can be operated in an open-loop configuration. The magnitude of the open-loop gain is typically large thus for a small difference between the noninverting and inverting input terminals, the amplifier output will be driven near the supply voltage. Without negative feedback, the LM741 can act as a comparator. If the inverting input is held at 0 V, and the input voltage applied to the noninverting input is positive, the output will be positive. If the input voltage applied to the noninverting input is negative, the output will be negative.
Closed-Loop Amplifier
In a closed-loop configuration, negative feedback is used by applying a portion of the output voltage to the inverting input. Unlike the open-loop configuration, closed loop feedback reduces the gain of the circuit. The overall gain and response of the circuit is determined by the feedback network rather than the operational amplifier characteristics. The response of the operational amplifier circuit is characterized by the transfer function.
Tech Tin Files: The history of the solid state Operational Amplifier uA741 (short story)
- The first germanium transistor op-amp appeared in 1958 with silicon versions in 1960. Nexus Research Labs offered the first pre-configured op-amp modules in 1962 followed shortly by Burr-Brown and Philbrick Researches.
- Amelco, Fairchild, RCA, TI, and Westinghouse developed early analog ICs. H. C. Lin of Westinghouse employed on-chip component matching and his lateral PNP patent on a custom op amp for the Autonetics Minuteman II missile in 1963. But the Fairchild uA702 op amp, created in 1964 by the team of process engineer Dave Talbert and designer Robert Widlar, was the first widely-used commercial product.
- Their 1965 successor, the uA709, established a mass market for analog ICs. Talbert and Widlar moved to Molectro (later acquired by National) in late 1965 where they built a linear dynasty beginning with the LM101. Then in 1968 Dave Fullagar of Fairchild one-upped the LM101 by adding an internal compensating capacitor to deliver the uA741, the most popular op-amp of all time.