Technical
How to Judge the Acceptance of PCB Quality
Which Color Circuit Board Sells the Most Expensive
Method to Solve the Noise Interference of Power Supply on High-frequency PCB Board
Disassembly Skills of Chip Components on PCB
What Factors Should Be Considered in the Selection of High-frequency PCB CCL
How to Place Special Components during PCB Layout
What Are the Functions of Capacitors in Circuits?
Testing Techniques for Common Electronics Components
What to do if There is a Short Circuit on the PCB
Desoldering Principles and knowhow during PCBA Processing
Black Oxidation of the Inner Layer of the Multilayer PCB
How to Ensure the High-performance Design of PCB
What Is the Printing Process of SMT Solder Paste?
PCB without fiducial mark, Is There Any Way to do SMT for It
What Are the Benefits of Reserving Break-up Tab for PCB Production
How Does SMT Affect PCB Production Time and Speed It Up
Classification of PCBs from three aspects
Common Problems and Solutions for Dry Film pasting during PCB Manufacturing process
Several Elements to Inspect after PCB Design
What is a halogen-free circuit board?
What Do Capacitive Coupling and Decoupling Mean?
What Are the Differences Between PCB Paste Mask and Solder Mask?
How PCBA Is Packaged and Shipped
How long can PCBA finished products be stored?
What Are the Differences and Relations Between PCB, PCBA, and SMT?
PCB Baking Specifications
PCB "Solder Mask Tenting" and "Solder Mask Opening"
Five reasons for PCB deformation and six solutions
Importance of first article inspection of PCBA board
Temperature zone standard for SMT reflow soldering
Small and medium volume PCB manufacturers in China
The main reason for PCBA cleaning
For power filter, the more capacitors, the better?
What does PCBA programming mean?
Content of PCB incoming testing
What conditions must be met for PCB circuit board soldering?
What is Blind via and Buried via
PCBA Manufacturers Temperature and Humidity Sensitive Components Management
Why choose Shenzhen SMT processing factory?
How long does it take to calculate the quotation for PCBA manufacturing?
Introduction of PCB design clearance requirements
Explanation of BOM, DIP, SMT, SMD
Introduction of the process of PCBA prototype
How to prevent pseudo soldering or cold soldering defects in PCBA manufacturing?
Factors that affect the Price of FPCB
What information is required for SMT processing at PCBA factory?
Skills of using 0ohm resistor in PCB design
How to select a PCBA manufacturer
SMT processing solder joint quality inspection
Characteristics difference between immersion gold PCB and gold plating PCB
Common malfunctions of Circuit Board Caused by Moisture
A Few Rules about PCB Panelization
Compare of multi-layer PCB with single/double layer PCB
Why do we need to introduce so many subdivided GND
Difference between immersion gold boards and gold plating boards
Aluminum PCB structure
Classification of different GND in circuit
Why PCB baking is necessary during manufacturing process
The handle and precautions of OSP board in SMT process
How to choose capacitors for filter decoupling
How to choose filter capacitor for switching power supply
5 database need for SMT process
Function of three-terminal capacitor
Introduction of PCB OSP surface treatment
Method of inspecting the quality of SMT by step
How to find the short point between VCC and GND
Difference between 850nm and 940nm infrared LED
Component layout of PCB SMT DFM
Pad shape influence on the strength and reliability of the soldering joints
The difference between high temperature solder paste and low temperature solder paste
Introduction to manual welding processing
Manual visual inspection in PCBA processing
Characteristics of the conformal coating process
Difference between hardware engineers and software engineers
PCBA processing operation rules
China PCB upstream materials has continued to soar
Difference between serial buses and parallel buses
The key points of quality control in PCBA processing
Common causes of solder beading during SMT process
Analysis of the advantages and disadvantages of HASL PCB surface
Requirements for layout of components during SMT assembly
Selection of electronic components and CCL for PCBA
Performance and appearance quality inspection of components.
Quality and Reliability of SMT Chip Processing and Production
Coupling and decoupling function of capacitor
Two methods to connect digital ground and analog ground
Common sense in SMT process

Introduction of Capacitors

Capacitance is a physical quantity that characterizes the ability of a capacitor to hold charge. The amount of electricity we need to increase the potential difference between the two plates of the capacitor by 1 volt is called the capacitance of the capacitor. The symbol of the capacitor is C. Capacitors are one of the most widely used electronic components in electronic equipment. They are widely used in blocking, coupling, bypassing, filtering, tuning loops, energy conversion, control circuits, etc. At the same time, it is also one of the chip components largely used in SMT processing plants. Use C to represent capacitance, the capacitance units are farad (F), microfarad (uF), picofarad (pF), 1F=10*6uF=10*12pF

1 farad (F) = 1000000 microfarad (μF) 1 microfarad (μF) = 1000 nanofarad (nF) = 1000000 picofarad (pF)
Naming method of capacitors: The name type of domestic capacitors generally consists of four parts (not applicable to pressure-sensitive, variable, and vacuum capacitors). They respectively represent name, material, classification and serial number.

1. How to determine the polarity of electrolytic capacitors:
Just use a multimeter to measure. Discharge the electrolytic capacitor first, then connect the test leads of multimeter to both pins of capacitor. the big swing is positive pole, but pay attention to: The positive pole of the pointer multimeter is opposite to the negative pole of the capacitor, the opposite of the digital meter, and the capacitor must be discharged between two measurements. You can also use the length of the pin to distinguish the positive and negative poles. The long leg is positive and the short leg is negative; the black mark block on the capacitor is the negative pole. There are two semicircles silkscreen on the position of the capacitor on the PCB, and the pin corresponding to the colored semicircle is the negative electrode.

2. Classification of capacitors:
According to its polarity, it is divided into two categories: polarized capacitors (such as electrolytic capacitors) and non-polarized capacitors.
According to the structure, it is divided into three categories: fixed capacitors, variable capacitors and trimmer capacitors.
Classified by electrolyte: organic dielectric capacitors, inorganic dielectric capacitors, electrolytic capacitors and air dielectric capacitors.
According to the purpose, there are: high-frequency bypass, low-frequency bypass, filtering, tuning, high-frequency coupling, low-frequency coupling, and small capacitors.

3. Capacitor capacity mark:
A. Direct marking method: Mark directly with numbers and unit symbols. For example, 01uF means 0.01 microfarad, some capacitors use "R" to indicate a decimal point, such as R56 means 0.56 microfarad.
B. Text symbol method: Use a regular combination of numbers and text symbols to indicate capacity. For example, p10 means 0.1pF, 1p0 means 1pF, 6P8 means 6.8pF, and 2u2 means 2.2uF.
C. Color code method: use color circle or color dot to indicate the main parameters of the capacitor. The color code method of the capacitor is the same as the resistance.

Capacitor deviation symbol in China: +100%-0--H, +100%-10%--R, +50%-10%--T, +30%-10%--Q, +50%-20% --S, +80%-20%--Z.

4. Commonly used capacitors: aluminum electrolytic capacitors, tantalum electrolytic capacitors, film capacitors, ceramic capacitors, monolithic capacitors, paper capacitors, trimmer capacitors, ceramic capacitors, glass glaze capacitors, mica and polystyrene dielectric capacitors.