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    • Cables, WiresCables, Wires 1. What are Cables and Wires?‌ ‌Cables‌: Made up of multiple individually insulated wires, the outer layer usually contains a protective layer, is used for power transmission, communication or signal transmission, and has a multi-conductor transmission function‌. ‌Wires‌: A single conductor (such as copper or silver), covered with an insulating material (such as plastic, rubber) on the outer layer, mainly used for low-power power or signal transmission. ‌2. What is the difference between Cables and Wires? ‌ ‌Structural Complexity‌: Cables are made up of multiple wires bundled with an additional protective layer, while wires are usually single conductors‌. ‌Application Scenarios‌: Wires are suitable for simple circuit connections; cables are mostly used in high-traffic scenarios, such as industrial control, fiber optic communications, etc.‌. ‌3. What are the Key Parameters of Cables and Wires?‌ ‌Bandwidth‌: Transmission capacity, measured by bit rate (bit rate, the number of bits transmitted per second). ‌Latency‌: The time it takes for data to travel from the sender to the receiver‌. ‌4. What are the Types of Cables and Wires? ‌ 1）Classification ‌By Material‌: including PVC, rubber, halogen-free cables, etc.‌ 2）Classification ‌By Function‌: ‌Flame-retardant Cable‌: can limit the spread of fire, suitable for scenarios with high safety requirements‌. ‌Fiber-optic Cable‌: used for high-speed…
      • Coaxial Cables (RF)Coaxial Cables (RF) ‌1. What are the Basic Structure of Coaxial Cables (RF)?‌ RF coaxial cable (RF Coaxial Cable) consists of four core parts: Inner Conductor: usually made of copper or silver-plated copper, responsible for signal transmission, the structure can be solid wire or multi-strand twisted wire; Insulation Layer: dielectric material (such as polyethylene, polytetrafluoroethylene) wrapped around the inner conductor, used for electrical isolation and supporting the structure; Outer Conductor: made of copper braided mesh or aluminum foil, plays an electromagnetic shielding role; Outer Sheath: the outermost protective material (such as PVC, PE) to resist environmental erosion.   ‌2. What are Coaxial Cables (RF) Used for?‌ RF coaxial cable is widely used in high-frequency signal transmission scenarios, including: Wireless communication (such as base stations and satellite communications);   Broadcast and television signal transmission;   Test equipment and radar systems;   Consumer electronics (such as satellite TV reception).   ‌3. What are the Types of Coaxial Cables (RF)? Divided into two categories according to impedance value: ‌50Ω Cable‌: mainly used for digital signal transmission and RF energy transmission (such as baseband signal); ‌75Ω Cable‌: commonly used in cable television (CATV) and video signal transmission.   ‌4. What are the Key Performance Characteristics of Coaxial Cables…
      • Flat Flex Cables (FFC, FPC)Flat Flex Cables (FFC, FPC) 1. What are Flat Flex Cables (FFC, FPC)? ‌FFC (Flexible Flat Cable)‌ It is a flat flexible cable made of extremely thin tinned flat copper wire sandwiched between PET insulating materials and pressed together by automated equipment.   It has a simple structure, usually a single-layer conductor arrangement, and the conductor spacing, margins, and other parameters can be customized.   ‌FPC (Flexible Printed Circuit)‌ It uses a flexible substrate (such as polyimide film) to form a circuit pattern through chemical etching technology and supports single-layer or multi-layer design.   It contains complex structures such as copper foil substrate and cover film, which can achieve high-density wiring.   2. Comparison of the Core Differences between FFC and FPC Dimensions FFC FPC Structure Single-layer flat conductor + Insulation layer laminated Etched flexible circuit board, Supports multiple layers Flexibility Flexible but regular shape, only suitable for simple bending Can be customized to any shape, Adapt to complex folding scenarios Production Process Lamination process, Low cost Etching superposition process, High complexity Connection Method Mostly use socket connector Support socket or flat cable clip connector   3. Where are Flat Flex Cables (FFC, FPC) Used? ‌FFC‌: Connection between the printer head and…
      • Flat Ribbon CablesFlat Ribbon Cables Flat Ribbon Cables have become a common wiring solution in industrial automation, electronic equipment, and other fields due to their compactness, flexibility, and reliability. 1. What are the Basic Structure of Flat Ribbon Cables? Conductor: Usually composed of multiple parallel tinned soft copper wires, such as 7-stranded conductors, to improve conductivity and flexibility. Insulation Layer: Made of materials such as soft PVC or FEP (fluorinated ethylene propylene), it is heat-resistant and oil-resistant, and can maintain the integrity of the insulation layer when torn. Band Form: The conductors are arranged side by side in a flat form to form a “ribbon” structure, and high-density connectors can be connected at both ends to save equipment space.   2. What are the Core Features of Flat Ribbon Cables? High Flexibility: It can be easily bent and curled, suitable for scenes that require frequent movement such as robotic arms and robots. Anti-interference: Through twisted conductors and shielding design, electromagnetic interference is reduced, suitable for signal transmission.   Environmental Resistance: Some models support oil resistance and high-temperature resistance (such as environments below 80 °C).   3. Where are Flat Ribbon Cables Used?‌ ‌Internal Wiring of Electronic Equipment‌: such as computer wiring, signal, and power connection in industrial control equipment‌.…
      • Modular – Flat CableModular – Flat Cable Modular Flat Cable is a high-performance cable that combines flat structure and modular design. It is designed for complex scenarios that require flexible wiring and frequent adjustments. 1. What are the Structural Characteristics of Modular Flat Cable? ‌Flat Flexible Design‌ Multiple flat wires are arranged in parallel, and the outer layer is wrapped with an insulating film or a tensile-resistant outer skin. The thickness can be as thin as 0.3mm, and the bending radius is as small as 4 times the cable thickness. It is suitable for narrow spaces and frequent bending conditions.   ‌Modular Interface‌ Supports customized configuration of the number of wires, spacing, and connection methods, allowing rapid expansion or replacement of functional modules (such as signal transmission, power supply, etc.) through standardized interfaces to improve system integration efficiency.   2. What are the Performance Advantages of Modular Flat Cable? ‌High Flexibility‌ In dynamic environments such as robots and automation equipment, it can be bent repeatedly with the movement of the equipment without breaking easily, reducing maintenance costs.   ‌Anti-interference and Stability‌ Reducing electromagnetic interference through twisted pair design or shielding technology to ensure the integrity of high-speed signal transmission is suitable for scenarios such as industrial…
    • Audio ProductsAudio Products 1. What are the Main Types of Audio Products? 1) Speaker Function: Converts audio electrical signals into sound energy output, and is the core component of the audio system. Technical features: Uses a pure piston drive design, combined with aluminum and damping materials to reduce distortion. Sensitivity, frequency response, and directional characteristics directly affect the sound quality. 2) Microphone Types: Including capacitive (ECM, MEMS) , dynamic, piezoelectric, etc. Application: Voice interaction, active noise reduction and recording scenarios, MEMS microphones have become the first choice for consumer devices due to their high consistency. Audio connector Structure: Divided into balanced, separate, and non-separate circuit designs, affecting anti-interference ability and signal transmission quality. Process requirements: The appearance must be free of burrs and leaks to ensure stability and durability. 3) Dynamic Unit Innovative technology: For example, the runway-type dynamic unit improves acoustic performance by optimizing the diaphragm material, which is suitable for professional microphones and micro speakers. 2. What are the Key Performance Parameters of Audio Products? ‌Nominal power and impedance‌: The speaker needs to match the rated power (such as 0.1W~200W) and impedance (4Ω~32Ω) to ensure compatibility‌. ‌Frequency response‌: Determines the audio coverage range, and high-end speakers can reach 23Hz~52kHz‌.…
      • MicrophonesMicrophones 1. Overview ‌ Microphone is a transducer device that converts sound wave signals into electrical signals. It is widely used in communication equipment, consumer electronics, medical instruments, and other fields. Its core function is based on the conversion of mechanical vibration caused by sound pressure changes and electrical parameters (such as capacitance and voltage) . ‌2. Classification and Working Principle ‌ 1) ‌Dynamic microphone ‌ Principle: Using electromagnetic induction, sound waves drive the diaphragm to drive the coil to move in the magnetic field, generating induced current. Features: Simple structure and durability, but low sensitivity, poor high-frequency response, suitable for human voice recording. 2) ‌Capacitive microphone ‌ Principle: Sound pressure causes the capacitance between the diaphragm and the backplate to change, and the bias voltage is provided by the charge pump. The signal is output after ASIC amplification. Subtypes: √‌MEMS microphone‌: The silicon-based diaphragm is etched using micro-electromechanical technology, and the ASIC chip is integrated. It has the characteristics of small size and good consistency. ‌ √‌Electret microphone ‌: The built-in electret material provides a fixed charge, and no external bias power supply is required. It is often used in consumer electronics products. ‌ 3) ‌Piezoelectric microphone‌ Principle: Utilize…
    • FiltersFilters Filters can effectively optimize signal integrity and improve the anti-interference ability and performance of electronic systems. 1. Filters Overview A filter is an electronic circuit or device used for signal processing. Its core function is to improve signal quality by selectively allowing specific frequency components to pass through while suppressing or attenuating other frequency components. Its application scenarios include communication systems, power management, audio processing, and RF front-end. 2. What are the Types of Filters? 1) Classification by frequency characteristics Low-pass filter (LPF): allows signals below the cutoff frequency to pass through, suppresses high-frequency noise, and is often used for power supply ripple smoothing. High-pass filter (HPF): allows signals above the cutoff frequency to pass through, and removes low-frequency interference (such as DC offset). Band-pass filter (BPF): only allows signals in a specific frequency band to pass through, and is used for signal frequency division in communication systems. Band-stop filter (BSF): suppresses signals in a specific frequency band (such as ground reflection interference in radar systems). 2) Classification by implementation method Passive filter: composed of passive components such as resistors, capacitors, and inductors, with low cost, but performance limited by component parameters. Active filter: combined with active components such as operational amplifiers, with high gain and strong…
      • Ferrite Disks and PlatesFerrite Disks and Plates Ferrite disks and plates provide a simple and cost-effective solution for radiated and inductively coupled electromagnetic interference. They can be utilized either as inductively coupled components or EMI shields, and can be installed directly on the EMI source.
      • DSL FiltersDSL Filters A DSL filter is an analog low-pass filter installed between analog devices (such as telephones or analog modems) and a plain old telephone service (POTS) line. The DSL filter prevents interference between such devices and a digital subscriber line (DSL) service connected to the same line. Without DSL filters, signals or echoes from analog devices at the top of their frequency range can reduce performance and create connection problems with DSL service, while those from the DSL service at the bottom of its range can cause line noise and other problems for analog devices.
      • Filter AccessoriesFilter Accessories Supplementary items used with other devices in this category.
    • CapacitorsCapacitors Capacitors play a vital role in electronic circuits. Reasonable selection and use are the keys to ensuring circuit performance. 1. Capacitors Overview A capacitor is a passive electronic component consisting of two conductors (plates) close to each other and a non-conductive insulating medium (dielectric) in the middle, used to store charge and electrical energy. Its core function is to achieve temporary storage and release of energy through the charging and discharging process. The calculation formula of capacitance (unit: Farad, F) is: C=εS/4πkd Where ε is the dielectric constant, S is the plate area, and d is the plate spacing. 2. What are the Core parameters of Capacitors? ‌Capacitance‌: There is a tolerance between the nominal value and the actual value, and the accuracy is usually 5%~25%. ‌Rated voltage‌: The maximum voltage limit for the normal operation of the capacitor. ‌Dissipation factor‌: Reflects the energy loss of the dielectric material and the equivalent series resistance (ESR). ‌Temperature coefficient‌: The effect of temperature change on capacitance, expressed in ppm (parts per million). ‌Leakage current‌: Determined by dielectric insulation performance, affecting long-term stability‌. 3. What are the Types of Capacitors? 1）‌Differentiation by polarity‌: ‌Non-polar capacitors‌: Such as ceramic capacitors and film capacitors, which can be installed in any direction, but have a small…
      • AccessoriesAccessories 1. Capacitors Overview Functional Positioning: Auxiliary accessories of capacitors are mainly used to install, protect, or optimize the performance of capacitors in circuits, including physical fixation, heat dissipation management, electrical connection, etc. Necessity: Capacitors must meet requirements such as stability and durability in circuits, and accessories can enhance their ability to adapt to complex environments (such as high temperature and vibration).   2. What are the Common Types of Capacitors? 1) Installation and Fixing Type Bracket/Fixing Clip: Ensure that the capacitor is firmly installed in the circuit board or equipment to avoid physical displacement. Insulation Sleeve/Sheath: Prevent the capacitor plate from contacting the external conductor and reduce the risk of short circuits. 2) Connection and Interface Type Terminal/Connector: Provide reliable electrical connection between the capacitor and the circuit, and need to adapt to different packaging types (such as plug-in type, surface mount type). Jumper/Lead: Used to adjust the position or connection method of the capacitor to adapt to a specific circuit layout. 3) Performance Optimization Category Heat Sink: Improve heat dissipation efficiency for heating problems of capacitors in high-power or high-frequency applications. Damper/Shock Pad: Reduce the impact of mechanical vibration on the internal structure of the capacitor and extend its service life.  …
    • Circuit ProtectionCircuit Protection 1. What are the Core functions of Circuit Protection? Circuit protection is a protection mechanism for electronic devices or systems against abnormal electrical conditions, mainly including the following functions: ‌Overvoltage protection‌: Prevent device breakdown caused by voltage transients (such as surges, and electrostatic discharge). Common protection components include varistors (MOVs) and transient suppressor diodes (TVSs). ‌Overcurrent protection‌: Prevent thermal damage to the circuit caused by current overload by fusing or current limiting. Typical devices include self-resettable fuses (PPTCs) and traditional fuses. ‌Temperature protection‌: Cut off the circuit by fusing or temperature-sensitive switches to prevent overheating, such as low-temperature alloy over-temperature protection components. ‌Compound protection‌: Integrated temperature, current, and voltage multi-monitoring protection solutions (such as TFR), widely used in high-safety demand scenarios such as lithium batteries. 2. What are the Main components and principles of Circuit Protection? ‌MOV (metal oxide varistor)‌ Absorbs transient overvoltage energy through nonlinear resistance characteristics, suitable for power line surge protection. ‌TVS (Transient Suppression Diode)‌ Quick response (nanosecond level) voltage spikes, used for ESD protection of precision circuits‌. ‌GDT (Gas Discharge Tube)‌ Uses the principle of gas ionization to discharge high-energy surges, with a current resistance of 20kA, suitable for lightning protection of communication equipment‌. ‌PPTC (Self-Resettable Fuse)‌ Overcurrent…
    • Discrete Semiconductor ProductsDiscrete Semiconductor Products Discrete semiconductor devices refer to a collection of semiconductor components with independent packages and single functions, which complement integrated circuits (ICs). 1. What are the Core Features of Discrete Semiconductor Products? ‌ ‌Independent packaging‌: Each device is packaged separately and can be directly soldered on a circuit board‌. ‌Single function‌: Focus on achieving specific functions (such as switching, amplification, rectification, etc.). ‌High flexibility‌: Supports building customized circuits by combining discrete devices to adapt to designs with special needs‌. 2. What are the ‌Common Types of Discrete Semiconductor Products?‌ ‌Diodes‌: Used for rectification, voltage regulation (such as Zener diodes), light emission (LED), etc. ‌Transistors：‌ √ Bipolar transistors (BJT): Current amplification and switch control‌. √ Field effect transistors (MOSFET/IGBT): High-frequency switching and power control (such as power supplies, motor drives)‌. ‌Thyristors‌: Used for high-power switches (such as dimmers and motor speed control)‌. ‌Power devices‌: such as power MOSFET, IGBT, etc., support high power density and efficient energy conversion. 3. Where are Discrete Semiconductor Products Used for?‌ ‌Automotive electronics‌: such as high-precision LDO series directly connected to the car battery, integrated output protection function. ‌Power management‌: Extend battery life through boost regulators and energy-saving functions (such as nPM2100 PMIC). ‌Industrial control‌: Including motor drive, power conversion, high current…
    • Inductors, Coils, ChokesInductors, Coils, Chokes All three are essentially inductors, and the differences in their names stem from the different emphasis on design goals, structural features, and application scenarios. 1. What are Inductors, Coils and Chokes?‌ ‌Inductor: A passive component that uses the self-inductance effect as its core principle to store magnetic energy and resist current changes through the principle of electromagnetic induction. Its basic functions include filtering, oscillation, waveform transformation, and cooperating with capacitors to achieve resonant circuits. ‌Coil: A multi-turn wire structure wound by enameled wire, usually as a physical implementation form of an inductor, widely used in electromagnets, transformers, radio transmitters, and other scenarios. ‌Choke: A specially designed inductor that is used to suppress high-frequency AC signals (such as radio frequency interference) while allowing DC or low-frequency current to pass. Its core function is to block unnecessary AC components through high reactance. 2. What are the Structural ‌Differences between Coils and Chokes?‌ ‌Coil‌: Usually a hollow or cored winding structure, the core material (such as ferrite, alloy powder core) can significantly increase the inductance value. For example, the “tank circuit” in the radio transmitter often uses a high-Q hollow coil. ‌Choke‌: The design emphasizes high-frequency impedance characteristics, often using core materials and optimizing the…
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  • Why Are PCB Stencils Key to SMT in PCB Assembly

    Why Are PCB Stencils Key to SMT in PCB Assembly?

    PCB stencils are metal plates with precisely cut openings. They have a very unique design. They make it possible for adhesives and solder paste to flow through the holes. Their only function is to

    By assypcbPublished On: January 20th, 2025Categories: Blog, PCB Assembly
  • The Initial Stage of PCB Manufacturing - PCB Layout Design

    The Initial Stage of PCB Manufacturing – PCB Layout Design

    A printed circuit board's component arrangement and electrical connections are referred to as the assembled circuit board layout. In essence, it is a map that indicates the locations of each component and how electrical

    By assypcbPublished On: January 20th, 2025Categories: Blog, PCB
  • Reflow Soldering - A Key Point of Printed Circuit Assembly

    Reflow Soldering – A Key Point of Printed Circuit Assembly

    One common technique for making SMT complete circuit boards is reflow soldering. The PCB that the components will be positioned on is covered with solder paste. Solder paste is applied to the PCB card on

    By assypcbPublished On: January 20th, 2025Categories: Blog, PCB Assembly
  • COB LED Assembled Circuit Board

    COB LED Assembled Circuit Board

    COB LED, Chip On Board LED boards represent a category of high-power LED light sources. These boards possess the capacity to encapsulate multiple LED chips on a singular aluminum substrate. The configuration of the COB

    By assypcbPublished On: January 20th, 2025Categories: Blog, PCB Assembly
  • A New Technology for Electronic Manufacturing

    Glass Circuit Board- A New Technology in Electronic Manufacturing

    As technology advances, many innovations are being introduced around the world. You can now see glass assembled circuit board being used in the circuit industry. You must be wondering now why it is necessary

    By assypcbPublished On: January 13th, 2025Categories: Blog, PCB Assembly
  • Drone Printed Circuit Assembly Design

    Printed Circuit Assembly Design for Drone

    The Drone PCB, a type of printed circuit board that is used in drone technology, is the brain. A flat, insulating sheet with conductive paths connecting electronic components. FR-4 laminates are flexible and durable, reinforced with glass

    By assypcbPublished On: January 13th, 2025Categories: Blog, PCB Assembly
  • The Secret Weapon Driving the Innovation of Electronic Devices

    Cavity Printed Circuit Board- The Innovation of Electronic Board

    Cavity printed circuit boards are high-performance boards featuring a unique cavity shape. Their recessed area enables more efficient use of space, which in turn enables consolidation and miniaturization of components such as microcontrollers and heat

    By assypcbPublished On: January 13th, 2025Categories: Blog, PCB
  • Basic Electronic Components

    Basic Electronic Components – The Ultimate Guide

    Every electronic device is made up of electronic components.To successfully complete any task, it is important to understand the components that compose an electronic system. Electronic components like resistors, diodes, and capacitors are used across

    By assypcbPublished On: January 13th, 2025Categories: Blog, Electronic Components
  • What Is MXM Connector

    What Is MXM Connector?

    Mobile PCI Express Module (MXM) is a set device interfaces that are based on PCI-Express for graphics processors and targeted to different types of notebooks. This not only allows for a shorter product development

    By assypcbPublished On: January 6th, 2025Categories: Blog, Electronic Components
  • What Is RF PCB

    What Is RF PCB?

    Are RF assemblies low-frequency or high-frequency? The operating frequency of RF components may range from very low frequencies up to extremely high frequencies. The RF range is 3kHz up to 300GHz. In practice however, the

    By assypcbPublished On: January 6th, 2025Categories: Blog, PCB
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