Phone PCBA

The telephone PCBA is the core circuit board component of the telephone. It integrates multiple functional circuits and realizes various communication and control functions of the telephone. The following is its introduction:

Hardware composition

• Main control chip: It is the core processor of the telephone, responsible for controlling the overall operation of the telephone, including processing incoming and outgoing call signals, controlling the display screen to display information, and coordinating the work between various modules.

• Audio processing circuit: It includes the driving circuit of the microphone and speaker, as well as the audio codec chip. It is responsible for converting sound signals into electrical signals for transmission, and converting the received electrical signals into sound signals for playback. At the same time, it can also filter and amplify the audio signals to ensure voice quality.

• Communication interface circuit: Usually there is an analog telephone line interface or a digital network interface. The analog interface is used to connect to the traditional telephone line to realize communication with the public switched telephone network (PSTN); the digital interface is used to connect to the IP network and support the Internet phone (VoIP) function.

• Display circuit: It consists of a liquid crystal display (LCD) or a light-emitting diode display (LED) and its driving circuit, which is used to display the incoming call number, call duration, menu information, etc.

• Key circuit: using membrane keys or conductive rubber keys, connected to the main control chip through the key matrix circuit. When the user presses the key, the key circuit will send the corresponding signal to the main control chip to realize dialing, answering, hanging up and other operations.

• Power circuit: convert the external input power (such as AC power through an adapter or battery power) into a stable DC voltage suitable for the operation of each chip and circuit, providing power support for the phone.

Working principle

• When the user picks up the handset to dial, the key circuit transmits the digital signal pressed by the user to the main control chip, and the main control chip sends the dial signal to the telephone network through the communication interface circuit. When there is an incoming call, the communication interface circuit receives the incoming call signal, the main control chip controls the ringing circuit to emit a ring tone, and displays the incoming call number on the display circuit. During the call, the audio processing circuit encodes and modulates the sound signal collected by the microphone, sends it out through the communication interface circuit, and decodes and amplifies the received sound signal of the other party, and plays it out through the speaker.

Features

• Basic communication functions: realize basic telephone communication functions such as voice calls, dialing, answering, and hanging up.

• Caller ID: can display information such as the caller number, making it convenient for users to identify the caller’s identity.

• Audio quality optimization: optimize the sound signal through the audio processing circuit to improve the voice clarity and sound quality.

• Multiple function extensions: some telephone PCBAs also support extended functions such as call waiting, call transfer, hands-free calling, recording, etc. to meet the needs of different users.

Application areas

• Widely used in homes, offices, hotels and other places. As a traditional voice communication device, it provides people with convenient communication services. With the development of technology, telephone PCBAs are also constantly upgrading to adapt to the development trend of digital communication and network communication. They are also widely used in some specific fields such as enterprise communication systems and smart office environments.