These Old Warhorses Refuse to Retire

Ten years ago, we at Techtime interviewed Bob Dobkin, a technological guru and the founder of Linear Technology. In this interview, Dobkin predicted that there would be a rise in demand for analog engineers. He also acknowledged that he finds it puzzling that only a handful of engineers choose to be analog designers.

“The analog market was always 15% of the electronics market, but the analog industry gets much fewer engineers, so there is a persistent shortage of analog engineers”. Dobkin, who had designed the innovative low dropout linear regulator LT3081, pointed out: “One of the earliest operational amplifiers (OP-AMP) in the industry, the LT1001, which was developed by us 30 years ago, is still in production and high demand.”

In fact, Analog Devices, which acquired Linear in 2016 for $14.8 billion, is still widely distributing LT1001 op amps and LT3081 regulators in 2023, ten years after this interview. They belong to a selected group of electronic components and integrated circuits (IC) called “Jellybeans”: Even though some are over 50 years old, they are still widely used, easily available, mass-produced, and in high demand on the market.

Everlasting Operational Amplifiers

Which components entered this hall of fame? The two most notable examples are the monolithic operational amplifiers (Op-Amp) 741 and LM101. OP-AMP, a concept characterized by very high input resistance and nearly limitless gain, was created by Bell Labs during World War II. The Op-Amp enabled the Allies to produce an anti-aircraft gun director systems with remarkable hit rates. However, these weren’t actual components; they were cumbersome small circuits. The first monolithic Op-Amp components were developed in the mid-60s but had many drawbacks.

Bob Dobkin describes the basics of LT3081. Credit: Techtime
Bob Dobkin describes the basics of LT3081. Credit: Techtime

The real revolution took place only in the second half of this decade: in 1965, Fairchild introduced the first classical amplifier, the uA709, which led National Semiconductor to introduce the LM101 in 1967. Fairchild responded by launching uA741 amplifier in 1968. The latter two are still available and are flying off the shelves. According to a cursory scan of Mouser and Digi-Key websites, Texas Instruments still manufactures the LM101 and versions of the 741 are also manufactured and sold by TI and Rohm, while non-branded bootlegs are manufactured in Asia.

The Hall of Fame

The most distinctive example of a Jellybean component that remains vital is the 555 Timer. It is based on two comparators and a digital memory circuit (Flip-flop), which creates timing solutions and oscillators using simple combinations of resistors and capacitors. The 555 was introduced in 1971 by Signetics, and according to various estimations, at least up to 2017, it sold more than 1 billion units annually. Companies including Texas Instruments, Rohm, Renesas, Analog Devices, Diodes, Onsemi, and the Chinese UMW continue mass producing it even today.

There are many components still regarded as fundamental parts in the industry, even after decades of use. For instance, RCA introduced the 2N3055 transistor in the early 1960s – Onsemi and Microchip continue to produce it today. The N2222 transistor, the BC456/7 audio amplifiers, the 78xx voltage regulators, as well as other components, are among the members of this hardball group.

It is more difficult to find Jellybeans the processors, as they are at the forefront of technological progress and are challenged by the increasing demand for processing performance and speed. Nevertheless, we can locate even here some components that refuse to disappear. such as Atmel’s (currently Microchip) AVR microcontroller family which is the basis for the Arduino platform, or new series of microcontrollers based on the old Intel’s 8051 family.

Processors from the 80s are still in production

The website of Rochester Electronics, which produces authorized versions of semiconductors that no longer produced by the original manufacturer, reveals the magnitude of this phenomenon: today, Rochester manufactures Intel’s 80186 microcontrollers introduced in 1982, and ADI’s ADSP-2101 signal processor introduced in 1989. We also found Motorola’s MC6802 CPU introduced in 1977, and a long list of logical components of the widespread 7400 family, developed by National Semiconductor in mid 1960s. These components are indeed old, but like old warhorses – they are still necessary, efficient, and get the job done.

Translated by P. Ofer