# linear integrated circuit > set of miniature electronic analog circuits formed on a single piece of semiconductor material **Wikidata**: [Q3233153](https://www.wikidata.org/wiki/Q3233153) **Wikipedia**: [English](https://en.wikipedia.org/wiki/Linear_integrated_circuit) **Source**: https://4ort.xyz/entity/linear-integrated-circuit ## Summary A linear integrated circuit is a set of miniature electronic analog circuits formed on a single piece of semiconductor material. Also known as an analog integrated circuit, it serves as a subclass of the broader category of integrated circuits. These components are fundamental in applications requiring continuous signal processing, such as timing, audio noise reduction, and television signal amplification. ## Key Facts - **Definition:** A linear integrated circuit is defined as a set of miniature electronic analog circuits formed on a single piece of semiconductor material. - **Parent Class:** It is a subclass of "integrated circuit." - **Aliases:** The entity is also known as "Analog integrated circuit" and "類比電路" (Chinese alias). - **Early Development:** Hybrid linear circuits for military applications (150 series) were established as early as 1960. - **Soviet Proliferation:** Numerous series were developed in the Soviet Union starting around 1970, including the 140, 157, 740, and 273 series. - **Notable Models:** Common examples include the 555 timer IC and the TL431 precision shunt regulator (incepted 1977). - **Applications:** These circuits are utilized in diverse roles such as vertical deflection in TVs (TDA3653), dbx noise reduction (AN6291), and voltage regulation. ## FAQs ### Q: What is the primary difference between a linear integrated circuit and a standard integrated circuit? A: A linear integrated circuit is a specific subclass of integrated circuit designed to handle analog signals. While standard integrated circuits can be digital or analog, linear ICs are specifically formed as miniature electronic analog circuits on a single piece of semiconductor material. ### Q: What are some common applications for linear integrated circuits? A: These circuits are widely used in signal processing and control applications. Specific examples from the knowledge base include timing (555 timer IC), television signal processing (TDA series), noise reduction (AN6291, LM1121), and military radar systems (175 series). ### Q: When were linear integrated circuits first developed? A: While general integrated circuits have a broad history, specific linear series such as the "150 series integrated circuits" (hybrid linear circuits for military applications) date back to 1960, with various other Soviet series appearing in 1970. ## Why It Matters Linear integrated circuits are essential components in the history of electronics because they consolidated complex analog functions into miniature, single-chip formats. Before their widespread adoption, analog signal processing—required for radio, television, and audio equipment—relied on bulkier discrete components. By forming these circuits on a single piece of semiconductor material, engineers achieved significant reductions in device size and power consumption. The impact of these circuits is evident in their diverse range of applications, from consumer electronics to military hardware. For instance, the development of specific ICs for color television (such as the TDA series for brightness, contrast, and saturation) revolutionized the reliability and cost-effectiveness of home entertainment. Similarly, specialized series for radio communications and radar (such as the Soviet 175 and 273 series) advanced capabilities in defense and telecommunications. The existence of standardized series, such as the famous 555 timer, demonstrates the technology's versatility and enduring relevance in electronic design. ## Notable For - **Analog Signal Processing:** Distinguished as a fundamental component for processing continuous analog signals rather than digital logic. - **Soviet Series Standardization:** Notable for the extensive development of numbered series (e.g., 548, 153, 140) specifically within the Soviet Union, covering everything from operational amplifiers to hybrid circuits for transceivers. - **Consumer Electronics Integration:** Recognized for enabling complex functions in televisions and audio equipment, such as the TDA2522 PAL detector and AN6291 noise reduction circuit. - **Longevity:** Specific designs like the 555 timer IC and TL431 regulator remain recognizable standards in electronics. ## Body ### Definition and Classification A linear integrated circuit is an electronic circuit formed on a small, flat piece of semiconductor material. It is categorized as a subclass of the general "integrated circuit." Synonyms include "Analog integrated circuit" and the Chinese term "類比電路." These circuits are characterized by their ability to process analog signals—continuous electrical signals that vary in amplitude. ### Historical Development and Soviet Series The development of linear integrated circuits saw significant activity in the mid-20th century, particularly within the Soviet Union, which produced a wide array of standardized series: - **Military and Hybrid Circuits:** The **150 series** (hybrid linear circuits for military applications) was established in **1960**. The **284 series** and **820 series** represented other hybrid analog circuits. - **1970s Expansion:** Several series were inceptioned in **1970**, including the **740 series** (caseless analogue integrated circuits), **157 series**, and **273 series** (hybrid ICs for portable transceivers). - **Operational Amplifiers:** The **140 series** and **553 series** were specifically developed as Soviet operational amplifier circuits. ### Key Components and Variants The knowledge base identifies numerous specific classes of linear integrated circuits designed for distinct functions: - **Timing and Regulation:** The **555 timer IC** is a prominent class for timing applications, while the **TL431** (incepted 1977) serves as a precision shunt regulator. - **Audio Processing:** The **AN6291** (incepted 1981) is designed for dbx noise reduction, and the **LM1121** functions as a Dolby B integrated circuit. - **Television Technology:** A significant portion of linear ICs are dedicated to video processing, including: - **TDA2522:** A PAL detector for analogue color TVs. - **TDA2560:** Controls brightness, contrast, and saturation in CRT sets. - **TDA3653:** A vertical deflection output circuit. - **TDA4440:** A video IF amplifier and demodulator. ### Specialized Applications Linear integrated circuits cover a broad spectrum of specialized uses: - **Radio and Radar:** The **175 series** consists of bipolar linear ICs for IF stages of radar and radio receivers, while the **826 series** serves communications radios. - **Sensors:** The **244 series** comprises hybrid amplifier ICs specifically for bioelectrical sensors. - **Voltage Regulation:** The **1162 series** is dedicated to voltage regulation integrated circuits.