Electronic components are the general name of components and devices. 1. components: the products processed by the factory have not changed their molecular composition, so they can be called components, and there is no need to source equipment. It includes: resistance, capacitance and inductance. (Also known as passive components) (1) Circuit devices: diodes, resistors, etc. (2) Connecting devices: connectors, sockets, connecting cables, and printed circuit boards (PCB). Second, devices: devices whose molecular structure changes during factory production and processing are called devices, which are divided into: 1. Active device, its main features are: 2. Discrete devices are divided into (1) bipolar transistors (2) field-effect transistors (3) thyristors (4) semiconductor resistors and capacitors (3) analog integrated circuits mainly refer to integrated circuits that integrate analog circuits such as capacitors, resistors and transistors to process analog signals. There are many analog integrated circuits, such as integrated operational amplifiers, comparators, logarithmic and exponential amplifiers, analog multipliers (dividers), phase-locked loops, power management chips and so on. The main circuits of analog integrated circuits are: amplifier, filter, feedback circuit, reference circuit, switched capacitor circuit, etc. Analog integrated circuit design is mainly obtained by experienced designers through manual circuit debugging and simulation, and the corresponding digital integrated circuit design is mostly automatically synthesized by using hardware description language under the control of EDA software. 4. Digital integrated circuit is a digital logic circuit or system that integrates components and wires on the same semiconductor chip. According to the number of gates or components and devices contained in digital integrated circuits, digital integrated circuits can be divided into small-scale integrated (SSI) circuits, medium-scale integrated MSI circuits, large-scale integrated (LSI) circuits, very large-scale integrated VLSI circuits and very large-scale integrated (ULSI) circuits. Small-scale integrated circuits contain no more than 10 gates or no more than 100 elements; The medium-sized integrated circuit contains 10 to 100 gates or 100 to 1000 elements; LSI contains more than 100 gates, or the number of components is between 10 and 10; VLSI contains more than 10,000 doors, or the number of components is between 10 and10. The number of components in VLSI is between 10 and 10. It includes: basic logic gate, trigger, register, decoder, driver, counter, shaping circuit, programmable logic device, microprocessor, single chip microcomputer, DSP and so on.