Capacitive touch screen is the most common one among mobile phones and other smart devices AD829JR Touch screen technology. It arranges a layer of conductive material on the touch screen. When the user touches the screen, the conductive material will sense the charge change of the touch point, and convert this information into digital signals, so as to achieve accurate recognition of the touch position. The capacitive touch chip is the key component for handling these charge changes and signal conversion.
Capacitive touch chip usually consists of the following main components:
1. Capacitance sensing layer: The capacitance sensing layer is the core part of the capacitive touch chip, which is usually composed of a layer of conductive material. When the user touches the screen, a capacitance will be formed between the finger and the conductive material. The conductive material will sense the change of this capacitance and convert its change into an electrical signal.
2. Signal conditioning circuit: the signal conditioning circuit is used to amplify, filter and digitize the electrical signal in the capacitive induction layer for subsequent data processing and analysis. Signal conditioning circuits usually include amplifiers, filters, analog-to-digital converters and other circuits.
3. Control circuit: the control circuit is used to control and manage the touch screen. It can detect touch events on the touch screen, identify touch positions, and transmit the identified touch data to the main processor for further processing. The control circuit can also realize the functions of multi touch and gesture recognition.
4. Data interface: the data interface is used to communicate with the main processor and transmit the processed touch data to the main processor. Data interface usually adopts standard serial communication protocol, such as I2C or SPI.
5. Power supply management circuit: the power supply management circuit is used to provide a stable power supply for the capacitive touch chip. It can filter and stabilize the input power supply to ensure that the capacitive touch chip can obtain sufficient power supply when working.
The working principle of capacitive touch chip is realized by sensing the capacitance change between the touch point and the conductive material. When the user touches the screen, a capacitance will be formed between the finger and the conductive material, and the electric field on the conductive material will change. Touching the capacitance sensing layer in the chip will sense the change of the capacitance and convert it into an electrical signal. The signal conditioning circuit will amplify, filter and digitize these electrical signals for subsequent data processing and analysis. The control circuit will detect and identify touch events, and transmit the identified touch data to the main processor. The main processor can implement different functions according to these touch data, such as moving, scaling and rotating.
Capacitive touch chip has the following advantages:
1. High precision: capacitive touch chip can realize high-precision recognition of touch position and accurately capture user's touch action.
2. High sensitivity: capacitive touch chip has high sensitivity to touch, can sense slight touch actions, and provide better user experience.
3. Multi touch: capacitive touch chip can realize multi touch function and support multi finger operation, such as double finger zoom and rotation.
4. Transparency: The capacitive touch chip can be directly installed on the display screen without affecting the display effect and maintaining the transparency of the touch screen.
5. Durability: The capacitive touch chip has no mechanical keys, is not easy to wear, and has a long service life.
In addition to the mobile phone touch screen, capacitive touch chips are also widely used in tablet computers, laptops, smart watches, car navigation systems and other devices. With the continuous development of technology, the performance and functions of capacitive touch chips are also improving, providing users with a better touch experience.
