What Are Analog Chips?

Analog integrated circuits mainly refer to integrated circuits that use analog circuits composed of capacitors, resistors, and transistors to process analog signals. There are many analog integrated circuits, such as operational amplifiers, analog multipliers, phase-locked loops, power management chips, and so on. The main constituent circuits of analog integrated circuits are: amplifier, filter, feedback circuit, reference source circuit, switched capacitor circuit, etc.

Analog integrated circuits ^[1]

In information technology, digital integrated circuits are the protagonists, whose processing objects are information carried by digital signals, and digital signals take discrete values in terms of time and quantity. However, the changes in time and quantity of signals in nature are continuous, such as wind sound and water flow. Such signals are called analog signals. Correspondingly, the circuits that process analog signals are called analog circuits, and are used to Integrated circuits that process analog signals are called analog integrated circuits. Obviously, digital circuits cannot directly deal with nature. It is only for the convenience of processing or transmission. In order to make full use of the advantages of digital systems, first convert analog signals to digital signals, and input them to large capacity, high speed, strong anti-interference ability, and confidentiality. After being processed by a good modern digital system, it is converted back to an analog signal output.

The protagonist of an integrated circuit is a transistor, and an analog integrated circuit is no exception, but it uses the amplification effect of a transistor, while digital integrated circuits use the switching effect of a crystal. Most of the early analog integrated circuits used bipolar transistors. Due to the maturity of the CMOS process, the shortcomings of the earlier CMOS circuits were slower, and they had the advantages of low power consumption and easy process upgrades (the proportion of CMOS is reduced). Analog integrated circuits and digital-analog hybrid integrated circuits (digital circuits and analog circuits are integrated) are also commonly designed and implemented with CMOS. ^[2]

The basic circuits of analog integrated circuits include current sources, single-stage amplifiers, filters, feedback circuits, current mirror circuits, etc. The higher-level basic circuits composed of them are operational amplifiers and comparators, and the higher-level circuits have switches Capacitor circuit, phase-locked loop, ADC / DAC, etc. According to the response relationship between the output and input signals, analog integrated circuits can be divided into two categories: linear integrated circuits and nonlinear integrated circuits. The response between the former's output and the input signal usually has a linear relationship. The shape of the output signal is similar to the input signal, but it is amplified and amplified by a fixed coefficient. The response of the output signal of the non-linear integrated circuit to the input signal has a non-linear relationship, such as a square relationship, a logarithmic relationship, etc., so it is called a non-linear circuit. Common non-linear circuits include oscillators, timers, and phase-locked loop circuits. The typical application of analog integrated circuits is shown in the figure below. Input the external natural signals collected by various sensors or antennas such as temperature, humidity, optics, piezoelectricity, acoustic electricity, etc., after preprocessing by the analog circuit, convert them into suitable digital signals and input them. In digital systems, the signals processed by the digital system are then post-processed by analog circuits, converted into sound, image, radio wave and other analog signals for output.

The use of analog ICs has been dominated by consumer electronics, which has maintained steady growth in recent years. According to Databeans' research report on the analog IC market, the global analog market has a compound growth rate of 12% from 2003 to 2009. This number is higher than the growth rate of other products. This also indicates that the high-performance analog market has great potential for development in the coming period. In the market statistics of the American Semiconductor Industry Association (SIA), there are also data that show that in the next two to three years, the development of the analog market will rapidly surpass the digital market. Analog devices will become the mainstream of analog integrated circuit applications in the digital age of the market and products.

Analog ICs are mainly used to perform analog signal reception, mixing, amplification, comparison, multiplication and division operations, logarithmic operations, analog-to-digital conversion, sample-and-hold, modulation-demodulation, step-up, step-down, step-down, Functions such as voltage regulation. Circuit forms include data converters (such as A / D converters, D / A converters, etc.), operational amplifiers, amplifiers, wideband amplifiers, etc., non-linear amplifiers (analog multipliers, digital / anti-log amplifiers, etc.), multiple Analog switches, (linear regulators, switching power supply controllers, etc.), intelligent power ICs. In the development of its design and process technology, analog IC has formed its own design ideas and process system; it meets the needs of information technology at the level of technological development, product types, and limits; its applications have penetrated into various fields In modern military and civilian electronic systems, simulation has played an important role; in various occasions of informatization, high-performance analog IC is inseparable. The level of analog IC performance often determines the level of electronic products or systems.

In terms of devices, because the requirements for analog ICs vary widely, in terms of devices, not only have more than ten categories of analog IC products developed, but also hundreds of thousands of products of various types of analogs, product types and performance levels. To meet the different needs of the application.

Among them, the data converter is an analog and digital mixed signal processing circuit, and its analog circuit part accounts for more than 50% of the chip area. As early as 1986, Professor Gray of the United States proposed to use the so-called "egg model" to vividly represent the digital IC, analog IC, and analog / digital conversion (A / D) circuits, and digital / analog conversion (D / A) circuits. relationship. He compared digital ICs to egg yolks, analog ICs to egg shells, and the A / D and D / A conversion circuits naturally became the egg whites connecting the two. It can be seen that the three are an organic whole. Real-world non-physical signals can be converted into digital signals by analog circuits and A / D conversion circuits, and then converted by D / A conversion circuits and analog circuits into analogs that we can perceive. signal. In terms of data converters, 8 to 14-bit 1 to 80 MHz high-speed A / D technology is very mature and there are sufficient products. A / D converter products with more than 16 bits and more than 30 MHz can also be seen. At the same time, in the A / D converter, not only analog ICs with integrated multiple functions appear, such as A / D converter subsystems such as multiplexers, instrument amplifiers, and amplifiers, but also other analog ICs and Various digital circuits such as DSP, memory, CPU, I / O, etc. are integrated together. American Analog Devices Corporation released the industry's first 16-bit quad digital-to-analog converter (DAC) in a 3 mm × 3 mm 10-lead LFCSP (lead-frame chip-scale package) ultra-small package in 2006 to meet industry and communications needs The need for ever-decreasing design size-this technology development will save up to 70% of printed circuit board area.

In terms of RF amplifiers, SiGe bipolar technology is being adopted to meet the high performance requirements of applications. Amplifiers are being used in a variety of handheld communication devices and require low power consumption. ADI (American Analog Devices Corporation) high-performance amplifier series (such as the AD8350 operating frequency reaches 1 200MHz, the noise figure is 6.1dB at 250MHz, has a high dynamic range, good linearity and common mode rejection), can Effectively used in communication transceivers, universal gain amplifier systems, A / D buffers, high-speed data interface drivers, etc. AD I recently released the first AD8352, which can effectively drive high-speed analog-to-digital converters (ADCs) of wireless infrastructure systems and achieve ultra-low distortion performance. AD8352, as the latest member of ADI's extended family of types, is suitable for driving next-generation 3G and 4G cellular and broadband WiMAX wireless basic equipment using 12-bit to 16-bit ADCs at the highest practical intermediate frequency (IF) conditions, driving high-speed ADCs up to 380 MHz, more than similar The differential amplifier can reach 100MHz and has the ability to maintain superior performance.

In terms of voltage regulators, the voltage regulator is integrated in the AD6121 IF subsystem introduced by AD I. It is an IF amplifier with a wide dynamic range. It is specially designed for CDMA (Code Division Multiple Access) system applications. Suitable for battery power work from 2. 9V to 4.2V. Motorola's voltage regulator series has low switching current, low noise, and extremely low quiescent current. It can be adjusted when the rated voltage of the battery power drops to less than 0.2V, which is very suitable for battery-powered systems such as cellular phones, cordless phones and long Lifetime battery-powered RF control system applications.

The root cause of the endless stream of electronic products today is not so much the rapid improvement of digital computing technology as the new results of analog technology. Compact, power-saving, entertainment, convenient .. It is analog technology that can meet consumers' requirements. Therefore, analog technology has created electronic products with different characteristics and grades, and has continuously created new requirements for the entire electronics industry. Therefore, only analog technology can make electronic products have a unique personality and highlight their own characteristics. ^[4]

Analog integrated circuit products are divided into three categories: the first category is general-purpose circuits, such as operational amplifiers, multipliers, phase-locked loops, active filters, and digital-to-analog and analog-to-digital conversion; the second is dedicated Circuit, such as audio system, television receiver, video recorder, communication system and other special integrated circuit series; the third type is monolithic integrated system, such as monolithic transmitter, monolithic receiver, etc.

• There are currently three prominent trends in analog circuits: high-performance discretes, analog-to-digital hybrids, and SOC (System on Chip).

There are many types of analog integrated circuits, and their performance requirements are also different. The pursuit of higher performance will be the main development direction of analog devices in the future [7]. Li Jinhua, Linear Technology's China regional business manager, simply summarizes it as "three rises and three drops", that is, speed, accuracy, and efficiency increase, while power consumption, size, and number of peripheral components decrease. For amplifiers, it will develop towards higher speed, lower noise, and greater dynamic range. For data converters, it will develop towards higher speed and higher precision. In signal processing, RF circuits, Power management and other fields will develop in the direction of higher accuracy, speed and efficiency, while power consumption, size and number of peripheral components will continue to decline. Taking mobile phones as an example, consumers demand clearer voices, more gorgeous screens, and longer standby time. These have placed higher requirements on analog device manufacturers, and brought more Big challenge. Discrete analog circuits can make these performances very high. For example, the conversion rate of Maxim has already achieved 2GSPS, but this performance cannot be achieved with SOC (System-on-Chip).

A single-chip switched capacitor filter (SCF) completes the processing of analog signals. With the continuous development of very large-scale ICs, the concept between analog and digital is constantly blurred. For example, the integrated filtering technology that is rapidly developing today is an example of an integrated circuit with analog and digital: it uses MOS switches, MOS capacitors and MOS operational amplifiers to be integrated in [8]. National Semiconductor's latest ADC081000 chip is a best example of analog and digital fusion. This 8-bit analog-to-digital converter has a low voltage differential signal (LVDS) interface with a maximum sample rate of 1.6 GHz, which is the fastest speed in the industry. Because this analog-to-digital converter has high-speed data acquisition capabilities, system designers can directly down-convert analog signals for faster and more efficient post-processing.

With the improvement of process level, the improvement of EDA tools, Foundry process PDK and the improvement of design level, analog IC is entering a new era of development. In order to ensure the best system performance, highest reliability, smallest volume, and lowest cost, the design and manufacturing of digital and analog ICs are moving towards a unified processing platform, from a single functional circuit to a system-level circuit. The most promising IC development direction-SOC.

SOC is a revolution in the field of microelectronics design. From the perspective of the entire system, SOC tightly combines intelligent cores, information processing mechanisms, model algorithms, chip structures, circuits at all levels, and device design. The chip completes the functions of the entire system, that is, we can design more and more circuits in the same chip, which may include a central processing unit (CPU), embedded memory (embedded memory), digital signal processor ( (DSP), digital function module (Digital function), analog function module (Analog function), analog-to-digital converter (A / D, D / A), and various peripheral configurations (USB, MPEG), etc. This provides designers with the latest means available for electronic system design and development. Using on-chip reprogrammable technology, so that the functions of the on-chip system hardware can be configured by programming like software, so that flexible and convenient changes and development can be performed in real time, and even reconfiguration can be performed without stopping during system operation , So that the same hardware can achieve different functions at different times, improving the efficiency of the system. This new system design concept makes the new generation of SOC more flexible and adaptable. It not only makes the design and development of electronic systems and the improvement and expansion of product performance very simple and convenient, but also makes electronic systems have better performance, lower power consumption, smaller size and lower cost. Here comes a revolutionary new change in the design and application of electronic systems, which can be widely used in mobile phones, hard drives, personal digital assistants and handheld electronics, consumer electronics, etc. SOC is a new platform for the development and application of electronic systems in the 21st century. TI company introduced the model as MSC120, which is an enhanced 8051 MCU with 8-channel 24-bit delta-sigma analog-to-digital / converter and single channel 8-bit digital-to-analog converter. With on-chip temperature sensor, I2C, SP I interface and low voltage monitoring function, it is very suitable for industrial applications, such as weighing, process control, intelligent sensors, etc.

• Analog circuit can be used as a starting point for the development of integrated circuits in China

After more than 30 years of development, China's integrated circuit industry has formed a good industrial foundation. In 2004, China's integrated circuit design industry and chip manufacturing industry have made breakthrough progress. The integrated circuit market demand reached 24.3 billion pieces. However, of these 24.3 billion integrated circuits, less than 8% of China's local real estate products. There are huge business opportunities, and it also reflects the gap between China's IC design industry and the international IC design industry. China's integrated circuit industry is facing unprecedented opportunities and challenges. China's consumer electronics industry maintained rapid growth in 2005, and demand for integrated circuit products increased significantly.

China's vast analog IC application market has brought sufficient development space for analog IC technology. Analog circuits can be used as the starting point for the development of integrated circuits in China in the future. Much of the knowledge to do CPU is not learned from books, but experience and tips. China lacks this kind of talent, and it needs a long time to accumulate experience. In addition, funding is also a problem. Each time the chip is cast, hundreds of thousands of dollars are required. It is normal for a high-performance CPU to cast seven or eight times. The level of Chinese integrated circuits in the field of general-purpose CPU products is even 20 to 30 years behind.

Therefore, we can avoid high-end CPUs and aim at the development trend of the international IC industry, namely SOC, and implement tracking and breakthroughs through the design of embedded chips. Because in digital design, almost everything can be done automatically; but analog circuits still rely on the wisdom of engineers to implement the design. The embedded chip IC manufacturing industry that combines analog and digital is not developed in terms of quality or quantity, but only to find out the direction of development, along with global production, we can give full play to our existing production capacity; moreover, It has many types and is widely used in different fields such as mobile phones, digital TVs, DVDs, TV set-top boxes, and PDAs. Unlike the highly standardized PC, which is unique to Intel, it is difficult for large foreign companies to form a monopoly.

Although the tide of the eastward shift of China's industry, the steady growth of China's economy, coupled with the huge domestic demand market, as well as abundant human resources and abundant natural resources, it can be said that the development of China's analog integrated circuits is well-timed, geographically advantageous, and Advantage. It is believed that in the near future, China will rise as the new world integrated circuit manufacturing center after the United States, Japan, Taiwan, South Korea, and Singapore.

"Analog Integrated Circuits" analyzes and discusses analog integrated circuits from the basic theory, unit circuits, integrated circuits, and applications around eight general analog integrated circuits. The book is divided into 9 chapters, including: introduction,

Professor Song Huanming has been engaged in teaching and scientific research in the field of electronic technology for more than 40 years, and has instructed multiple masters in communication and electronic information. He has twice won the Lop Teaching Fellowship of Southeast University. Author of "Electronic Circuits", "Basic Principles of Microcomputers", "VLSI Technology" (translation), "Switch Capacitor Data Collection" and so on.

Publishing instructions

Foreword

Teaching Suggestions

Symbol Description

Chapter 1 Introduction

1.1 Development of Analog Integrated Circuits

1.2 Characteristics of analog integrated circuits

1.3 Analog ICs

Model name

M001 2P4M Triac

M002 4N35 Universal Photocoupler

M003 6N135 Digital logic isolation

M004 24C01 1K / 2K 5V I2C bus serial EEPROM

M005 24LC08B 8K I2C-bus serial EEPROM

M006 93C46 1K serial EEPROM

M007 AD574 12-BIT, DAC converter

M008 BM2272 remote decoder

M009 CA3140E 4.5MHz, BiMOS Operational Amplifier

M010 TLP521 Programmable AC / DC Input Solid State Relay

M011 7805 Positive 5V Three-terminal Regulator IC

M012 LM7905 negative 5V three-terminal voltage regulator integrated circuit

M013 LA7806 B / W TV sync, deflection circuit, 16PIN

M014 7906C negative 6V three terminal voltage regulator integrated circuit

M015 7808A positive 8V 3-terminal regulator, input 35V, power 20.8W

M016 7908AC positive 8V 3-terminal regulator, input 35V, power 12W

M017 LM7809 Positive 9V Three-terminal Regulator IC

M018 ADS7809 Positive 9V Three-terminal Regulator IC

M019 TA7810S 0.5A, 3-terminal regulator

M020 TDA7910N negative 10V 3-terminal regulator, input -35V, 1A, power 12W

M021 IRF7811A N-MOSFET, power MOSFET, 28V / 11.4A / 2.5W

M022 7812A positive 12V 3-terminal regulator, input 35V, power 20.8W

M023 LM7912 1A 3-terminal regulator

M024 AD7813 2.5V-5.5V, 400kSPS, 8 / 10-BIT, sampling, ADC converter

M025 LM7815 Positive 15V Three-terminal Regulator IC

M026 LM7915 negative 15V1A 3-terminal regulator

M027 AD7819 2.7V-5.5V, 200KSPS, 8-BIT, sampling, ADC converter

M028 LA7820 color TV sync / deflection circuit

M029 L7920C negative 20V1A 3-terminal regulator

M030 LC7821 analog switch

M031 LM7824 Positive 24V Three-terminal Regulator IC

M032 KA7924 negative 24V1A 3-terminal regulator

M033 AD7825 3Vto5V, 2MSPS, 1/4/8 channel, 8BitAD converter

M034 PJ7925CZ negative 25V1A 3-terminal regulator

M035 ADS7826 2.7V power supply for 10/8 / 12-bit sampling analog-to-digital converter

M036 IRF840 power FET, high power, high speed, 500V / 8A / 125W

M037 ADC0809 8-BIT up compatible 8-channel multiplexer A / D converter

M038 ADC0832 2 channels, 8-BIT serial input / output A / D conversion multiple selection

M039 LM324N Quad Operational Amplifier

M040 LM339 Low Power Low Offset Voltage Quad Comparator

M041 LM358 Low Power Dual Operational Amplifier

M042 LM386 Low-Voltage Audio Amplifier

M043 LM747 Dual Operational Amplifier

M044 LM2717 Buck / Boost Converter Two Pulse Width Modulation (PWM) DC / DC Converters

M045 AT24C01A serial (1K, 128 × 8)

M046 AT28C17 16K EPROM

M047 AT8 9C51 low power / low voltage, high performance 8-bit microcontroller

M048 AT89C52 8K Bytes flash memory, 8-bit microprocessor

M049 BT136 Triac

M050 GAL20V8B programmable logic device

M051 HS2262A Low Power Universal Encoder

M052 HT24C02 memory

M053 IC7109 3 and a half ADC / LED driver

M054 ICL7106CPL Similar to three and a half bit conversion

M055 ICL8038CCJD Precision Waveform Generator / Volt Controlled Oscillator

M056 AD9215 10-BIT, 65/80 / 105MSPS, 3V, A / D converter

M057 ICL8038CCPD Precision Waveform Generator / Volt Controlled Oscillator

M058 LF353 Dual Channel Power Amplifier

M059 LF398 power amplifier

M060 LM111-211-311 Differential Comparator with Filter

M061 LM124X-4 Low Power Quad Operational Amplifier

M062 LM311P Single Channel, Gated Differential Comparator

M063 LM317T 3-terminal adjustable voltage regulator

M064 LM318 Single High Speed Universal OP

M065 LTC1595 Continuous 16-Bit Multiplier DAC

M066 M2764A-2F1 NMOS 64K 8K x 8 UV EPROM

M067 MAX232CPE Linear Transceiver, 2 Drivers, 16PIN

M068 MC1403 Precision Low Reference Voltage

M069 MJE2955T transistor

M070 MJE13005 Transistor

M071 MK2716 HDTU Clock Synthesizer

M072 NE5532AP dual low noise operational amplifier

M073 NE5532P dual low noise operational amplifier

M074 NE5534P Low Noise Operational Amplifier

M075 NJM2217 Video signal overlay with automatic frequency control

M076 AT28C64B

M077 SST39SF02-70-4C-NH

M078 ST13007DFP

M079 TC14433AEJG 3 and a half A / D converter

M080 TDA2003 10W Car Radio Audio Amplifier

M081 TEA2114 4096 Bit Static RAM

M082 TH7814A 50 MHz 2048 pixel linear array CCD Sensor

M083 TIP31C PNPDARL silicon INGTON transistor

M084 TIP41C PNPDARL silicon INGTON transistor

M085 TIP42C PNPDARL Silicon INGTON Transistor

M086 TIP127 PNPDARL silicon INGTON transistor

M087 TIP122 PNPDARL silicon INGTON transistor

M088 TL084CN

M089 TLC7135C ADC / LCD driver BCD output

M090 TM7282

M091 TRSTE-8532A

M092 ULN2003AN Seven-segment drive display

M093 W28EE011

M094 GAL22V10 high performance, E2COMS, programmable logic device

M095 GAL16LV8 low voltage, E2COMS, programmable logic device

M096 HM472114

M097 ADS7817

M098 LC7930

M099 PM7830

M100 PM7832

M101 T7932

M102 TPS2817