Capacitive touch screen interface refers to the interface used to connect the capacitive touch screen module and the main control board. With the continuous development of capacitive touch screen technology, its interface types are also increasing. This article will introduce the classification of capacitive touch screen interface and their respective characteristics.
1.I2C interface
I2C (Inter-Integrated Circuit) interface is a serial communication protocol, the use of two-wire system, you can simultaneously transmit data and clock, I2C interface is commonly used in low-speed communication between devices. The capacitive touch screen module communicates with the main control board through the I2C interface and transfers data through the I2C bus.
2.SPI interface
SPI (Serial Peripheral Interface) interface is a high-speed serial communication interface, using a 4-wire system (clock line, data input line, data output line, chip select line).SPI interface has a fast communication speed, high reliability, suitable for the communication speed of the system has high requirements. Capacitive touch screen module communicates with the main control board through SPI interface, which is faster than I2C interface.
3.USB interface
USB (Universal Serial Bus) interface is a commonly used communication interface designed to connect computers and other devices. In the capacitive touch screen module applications, the USB interface can be connected through the OTG (On-The-Go) technology to achieve the capacitive touch screen module as a "slave" access to the main control board.
The two commonly used interfaces are IIC and USB, mainly based on the product structure or host interface to determine the touch screen interface you want to choose, structure, thickness.
Some customers want USB interface, due to the host or product interface, or space is not enough to put the control card inside, so had to choose the IIC interface programme capacitive touch screen, IIC interface also has the benefits of the IIC interface.
USB interface capacitive touch screen than the IIC interface is convenient and simple, such as plug and play, do not need to adjust the driver data, transport is also faster than the IIC.