Damage to electronic components is generally difficult to detect by observers. In many cases, instruments are required for detection and judgment. Therefore, let's learn about the characteristics of the actual performance of various components.
Faults, whether caused by natural wear and tear or human error, can generally be categorized into three types: open circuits, damaged electronic components, and software malfunctions. Open circuits, such as broken wires, disconnected connectors, or poor contact, are usually relatively easy to repair. However, damaged electronic components (aside from obvious burnout or overheating) are generally difficult for observers to detect. In many cases, instruments are required for diagnosis. Therefore, for repair personnel, understanding the characteristics of various component failures is crucial for troubleshooting circuit faults and improving repair efficiency. The following are some characteristics of common electronic component failures.
1. Integrated circuits are generally subject to localized damage such as breakdown, open circuit, or short circuit. Power amplifier chips are prone to damage, memory chips are prone to software failures, and other chips may sometimes have poor soldering.
2. Transistor: breakdown, open circuit, severe leakage, deteriorated parameters.
3. Diodes (rectifiers, light emitters, voltage regulators, varactors). They are easily broken down, resulting in an open circuit, which increases the forward resistance and decreases the reverse resistance.
4. Resistors; Under normal circumstances, the efficiency of resistors is relatively low. However, resistors play a significant role in circuits. In some important circuits, changes in resistance value can cause changes in the quiescent operating point of transistors, leading to malfunctions in the entire circuit. The effects of resistor deterioration include: detachment from solder joints, increased or decreased resistance value, and worsened temperature characteristics.
5. Capacitors; divided into polarized electrolytic capacitors and non-polarized electrolytic capacitors. The practical characteristics of electrolytic capacitors are: breakdown and short circuit, increased leakage current, reduced capacitance, or open circuit. The practical characteristics of non-polarized capacitors are: breakdown and short circuit or detachment, severe leakage current, or resistive effect.
6. Inductance; its practical characteristics are: open circuit and desoldering.
The above are some of the main components. There are also some peripheral components such as field-effect transistors and quartz crystals that should not be ignored during maintenance. In particular, quartz crystals that are easily damaged by vibration and high-power devices (power amplifiers, power supply circuits, voltage-controlled oscillators) may have problems, such as not being able to turn on the device, not being able to connect to the internet after turning on the device, not being able to hear the other party's voice, and having to contact the supplier.
