Understanding Mobile Phone Circuit Boards: Components and Repair Techniques

Posted by Thomas Kakin on June 23rd, 2023

Mobile phone circuit boards are the brains of mobile phones. They contain various components and circuits that control the functions and features of the phone, such as the display, the camera, the speaker, the microphone, the antenna, the battery, the memory, the processor, and the software.

Mobile phone circuit boards are also known as PCBs (printed circuit boards) or motherboards. They are made of thin layers of fiberglass or plastic that are coated with copper traces and solder pads. These traces and pads connect the components and circuits on the board using soldering or reflowing techniques.

Mobile phone circuit boards are complex and delicate devices that can get damaged or malfunction due to various reasons, such as physical impact, water exposure, overheating, short circuit, corrosion, or software bugs. When this happens, the phone may not work properly or at all.

In this guide, we will explain some of the common components and circuits on mobile phone circuit boards and some of the repair techniques that can be used to fix them.

Components and Circuits on Mobile Phone Circuit Boards

Mobile phone circuit boards have different sections that perform different functions. Some of the common sections are:

  •          Power section: This section is responsible for supplying power to the phone from the battery or the charger. It contains components such as power ICs (integrated circuits), charging ICs, boost coils, capacitors, resistors, diodes, transistors, and fuses. The power section also regulates the voltage and current levels for different parts of the phone.
  •          Network section: This section is responsible for receiving and transmitting signals from the network provider. It contains components such as network ICs, PFOs (power frequency oscillators), PA (power amplifiers), filters, couplers, duplexers, switches, antennas, and SIM card slots. The network section also modulates and demodulates the signals for different frequencies and standards, such as GSM (global system for mobile communications), CDMA (code division multiple access), or LTE (long term evolution).
  •          Audio section: This section is responsible for producing and processing sounds from the phone. It contains components such as audio ICs, speakers, microphones, earpieces, buzzers, vibrators, and headphone jacks. The audio section also amplifies and filters the sounds for different modes and volumes.
  •          Display section: This section is responsible for displaying images and texts on the screen of the phone. It contains components such as display ICs, LCD (liquid crystal display) connectors, touch screen connectors, LEDs (light emitting diodes), backlight ICs, and flex cables. The display section also controls the brightness and contrast of the screen.
  •          Camera section: This section is responsible for capturing photos and videos from the phone. It contains components such as camera ICs, camera connectors, camera modules, flash ICs, flash LEDs, and flex cables. The camera section also processes and stores the images and videos on the memory of the phone.

Memory section: This section is responsible for storing data and programs on the phone. It contains components such as memory ICs (flash memory or RAM), CPU (central processing unit), RTC (real time clock), UEM (universal energy manager), BSI (battery status indicator), IMEI (international mobile equipment identity), SIM lock ICs and other security ICs. The memory section also manages the data and programs for different functions and features of the phone.

Repair Techniques for Mobile Phone Circuit Boards

Mobile phone circuit boards can be repaired using various techniques depending on the type and extent of the damage or malfunction. Some of the common repair techniques are:

  •          Cleaning: This technique is used to remove any dirt, dust, moisture, or corrosion from the circuit board and its components. It can be done using a soft brush, a cotton swab, a blower, an ultrasonic cleaner, or a cleaning solution. Cleaning can improve the contact and conductivity of the components and circuits and prevent further damage.
  •          Soldering: This technique is used to join or rejoin any broken or loose components or circuits on the circuit board using a soldering iron, a solder wire, a solder paste, or a solder flux. Soldering can restore the electrical connection and functionality of the components and circuits and prevent short circuits or open circuits.
  •          Desoldering: This technique is used to remove or replace any damaged or faulty components or circuits on the circuit board using a desoldering iron, a desoldering wire, a desoldering pump, or a hot air gun. Desoldering can remove the defective components and circuits and prevent them from affecting the performance or safety of the phone.
  •          Reflowing: This technique is used to reattach or reball any loose or detached ball-type ICs (integrated circuits) on the circuit board using a reflow machine, a BGA (ball grid array) kit, a stencil, or a heat gun. Reflowing can reestablish the contact and communication of the ball-type ICs and prevent them from causing errors or glitches on the phone.
  •          Jumpering: This technique is used to bypass or bridge any broken or missing traces or pads on the circuit board using a jumper wire, a soldering iron, and a solder wire. Jumpering can restore the electrical path and signal flow of the traces or pads and prevent them from causing faults or failures on the phone.

Conclusion

Mobile phone circuit boards are the brains of mobile phones that contain various components and circuits that control the functions and features of the phone. Mobile phone circuit boards can get damaged or malfunction due to various reasons, such as physical impact, water exposure, overheating, short circuit, corrosion, or software bugs.

By understanding some of the common components and circuits on mobile phone circuit boards and some of the repair techniques that can be used to fix them, you can troubleshoot and repair your phone yourself or seek professional help from mobile repair in Enfield.

They have a team of experienced and qualified technicians who can handle any mobile repair issue in no time and at a reasonable price.

Like it? Share it!


Thomas Kakin

About the Author

Thomas Kakin
Joined: June 6th, 2023
Articles Posted: 485

More by this author