What are Analog Electronics?

An analog circuit is a circuit used to transmit, transform, process, amplify, measure, and display analog signals. An analog signal is an electrical signal that changes continuously. Analog circuits are the basis of electronic circuits. They mainly include amplifier circuits, signal operation and processing circuits, oscillator circuits, modulation and demodulation circuits, and power supplies. ^[1]

Analog circuit

(electronic circuit)

1. The value of the function is unlimited;

I. Semiconductor devices

Including semiconductor characteristics, semiconductors

(1) Amplifying circuit: used for signal voltage, current or power amplification.

(2) Filter circuit: used for signal extraction, transformation or anti-interference.

(3) Operation circuit: completes the signal's ratio, addition, subtraction, multiplication, division, integration, differentiation, logarithm, exponent and other operations.

(4) Signal conversion circuit: used to convert the current signal into a voltage signal or convert the voltage signal into a current signal, convert a DC signal into an AC signal or convert an AC signal into a DC signal, and convert a DC voltage into a ratio proportional to it Frequency of

(5) Signal generation circuit: used to generate sine wave, rectangular wave, triangle wave, sawtooth wave.

(6) DC power supply: convert 220V, 50Hz AC power into DC power with different output voltage and current, as the power supply for various electronic circuits.

Analog circuits can be divided into two categories: standard analog circuits and application spacific analog ICs. The former accounts for 37% of the market and the latter accounts for 63%. According to the report of ICInsight, the two totaled $ 31 billion in 2000. A substantial increase of 40% over the previous year. According to the latest forecast of WSTS (World Semiconductor Trade Statistics Association) in the fall of 2012, the world's analog circuit market was 30.63 billion US dollars in 2000, an increase of 20% in 2013 to 36.88 billion US dollars, and an average annual growth rate of 19.5% from 1999 to 2003 . Standard analog circuits include amplifier interface circuits, data converters, comparators, regulators, and reference circuits. In 2000, it totaled $ 11.4 billion, of which the regulator and the reference circuit had the largest proportion, accounting for 13% of the entire analog circuit market, followed by amplifiers, accounting for 10%, interface circuits, 8%, data converters, 6%, and comparators, 1%. The dedicated analog circuit market refers to circuits used in consumer electronics, computers, communications, automotive, and other sectors of the industry. In 2000, a total of 19.2 billion US dollars. In the entire analog circuit market, dedicated analog circuits accounted for 22%, consumer products accounted for 16%, automobiles accounted for 9%, computers accounted for 8%, and industrial and other applications accounted for 7%.

The driving force behind the rapid development of analog circuits is, first of all, the continuous development of product digital systems, which must rely on analog devices to communicate with humans, and promote the expansion of the latter. Digital products include cellular phones, PDAs, displays, audio equipment, keyboard Ethernet and DSL products, and manufacturers such as Linear Technology Maxim ST and TI. Driven by portable products, power management integrated circuits have also grown rapidly. Second, the process technology has become increasingly finer, and the circuit geometry has become smaller. For example, the process technology has been reduced from 0.35 microns to 0.25 microns to 0.1 microns, with excellent quality. It is difficult to integrate analog circuits. Therefore, designers have to make analog circuits in a small package to pull the development of discrete analog circuits. Third, the convergence of voice and data communications also has a positive impact on analog circuits. Voice-over-cable for TV cable, voice-over-packet protocol for digital subscriber line, etc. all have a large dependence on analog and mixed-signal circuits. Fourth, as equipment power drops from 5V to 3V, and sometimes even 1.8V, power handling becomes increasingly important, thereby promoting the development of AC / DC converters, DC / DC converters, and power management ICs. Portability, connectivity, and power handling are the three major technology directions that analog integrated circuit production must face. Passive component integration, performance maintenance, and shortened time to market are the three major themes of analog IC manufacturers' production and operation. For example, the integration of passive components on RF modules is very important. Without paying attention, passive components may occupy the largest space on the board. Since the functions are integrated, there is a potential trade-off in performance, and the importance of time to market is self-evident. Switching power supply DC / DC converters will generate noise, which is another major issue facing analog integrated circuit manufacturers. In terms of communication infrastructure, manufacturers must also meet hot plugging. In the reconfiguration and maintenance of equipment, when one board replaces another, the entire system does not need to be turned off by hot plugging. The world's largest companies engaged in the production of analog integrated circuits are, in turn, TI (US $ 2.8 billion in revenue in 1999, market share of 13%), ST (US $ 2.3 billion, 10%); Philips (US $ 1.9 billion, 9%), Infineon ($ 1.7 billion, 8%), ONSemi ($ 1.5 billion, 7%), NS ($ 1.4 billion, 6%), and AD ($ 1.3 billion, 6%). These seven companies together account for 60%. .