Introduction to PCB Assembly

PCB Assembly Devices are divided into:
1. The main characteristics of active devices and PCB assemblies are: (1) self consumption of electrical energy (2). They also require external power supply.

2. Discrete devices, divided into (1) bipolar crystal transistor (2) field-effect transistor (3) thyristor (4) semiconductor resistor capacitor

3. Linear integrated circuit mainly refers to the integrated circuit composed of capacitors, resistors, transistors and other analog circuits integrated together to process analog signals. There are many Linear integrated circuit, such as integrated operational amplifiers, comparators, logarithmic and exponential amplifiers, analog multipliers (dividers), phase-locked loops, power management chips, etc. The main components of Linear integrated circuit are: amplifier, filter, feedback circuit, reference source circuit, Switched capacitor circuit, etc. The Linear integrated circuit design is mainly obtained through manual circuit debugging and simulation by experienced designers, and the corresponding digital integrated circuit design is mostly generated automatically by using Hardware description language under the control of EDA software.

4. Digital integrated circuits are digital logic circuits or systems that integrate components and wiring onto the same semiconductor chip. According to the number of gate circuits, elements, 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, ultra large scale integrated VLSI circuits, and ultra large scale integrated (ULSI) circuits. A small-scale integrated circuit contains no more than 10 gate circuits or no more than 100 components; Medium scale integrated circuits contain between 10 and 100 gate circuits, or between 100 and 1000 components; Large scale integrated circuits contain more than 100 gate circuits or between 10 and 10 components; Very Large Scale Integration contains more than 10000 gate circuits, or between 10 and 10 components; The number of elements in ultra large scale integrated circuits ranges from 10 to 10. It includes: basic logic gates, triggers, registers, decoders, drivers, counters, shaping circuits, programmable logic devices, microprocessors, microcontrollers, DSP, etc.