How to do anti-electromagnetic interference for TFT display?

With tft display, people are not only affected by electromagnetic fields, but also by other communication devices, which is EMI. when operating, they become electromagnetic sources, forming a magnetic field around them and radiating electromagnetic waves outward. The size of the field strength and radiation force depends on the power of the device.

The TFT display is a pure input or passive component of the entire system. The TFT display itself has no error correction function, that is, the TFT display can receive any signal that satisfies the satisfactory action timing relationship without judging whether it is right or wrong. Incorrect signals and data will cause incorrect control instructions or incorrect display images, resulting in incorrect display effects. To eliminate interference, first find out the interference source and the affected parts, and then eliminate, weaken, shield and remedy them through effective means.

The tft display has no display, and there is no response to the contrast adjustment. The reason for this phenomenon is that the tft display power or signal lines are subjected to electromagnetic interference during the whole machine, resulting in a reset of the tft display. The reset results in initializing the module's internal registers while turning off the display.

The following method is recommended: if interference is applied to the power line, it is recommended that the voltage regulator capacitor (10uf) and filter capacitor (0.1uf or 0.01pf) be combined to the power line VDD closest to the tft display. if interference is applied to the signal line, it is recommended that the VSS signal be added to the signal closest to the location of the tft display, with capacitance selected to be 0.1uf or 0.01uf. The above capacitance values are determined based on actual test results.

The picture will produce a typo or confusion (wrong information), or the picture moves, upside down. Sometimes it can not be recovered, only clear the screen and rewrite, or even need to repower and initialize the registers to recover. This is mainly due to interference with control signals, such as /WR,RD,E, or /CS, which produce interference.

On these signal lines, interfering signals can easily generate incorrect waveforms, leading to incorrect modification of register parameters and incorrect writing of data to the display unit. When the system is running, most programs only write to the data in the local display area, and there is no write operation to other addresses, nor is there any duplication of settings only for the initialization registers.

Shenzhen ORIC Display specializes in the research and development of TFT display, LCD display, OLED display, touch screen and other small and medium-sized liquid crystal display. To provide you with a solution to provide the right choice of display program.