How to repair laptop touch screen ghost touch

The hardware failures that the notebook screen click when no touch divided into 5 categories:

(1) Touch screen hardware channel is damaged

(2) Touch screen firmware version is too low

(3) The touch screen operating voltage is abnormal

(4) Radio frequency interference

(5) The touch screen calibration is abnormal

Hardware channel damage

1. Phenomenon:

Clicking on a certain area of ​​the screen, no response, but around the area is sensed, resulting in a touch event.

2. Problem Analysis:

The sensing area of ​​the screen is composed of a strip of sensing channels. If some sensing channels are broken, when the area is clicked, the screen cannot sense the electric field and the screen changes, so there is no response when clicking on the area, but around Adjacent normal channels sense changes in the electric field, so touch events occur in that area. The feeling is that the area is touched, but another area responds.

3. How to fix:

Replacement Screen

Screen firmware version is too old

1. Phenomenon:

The screen can be used normally, but the pressed area and the response area are mirrored, for example, according to the right side of the left area, and the left side of the right area.

2. Problem Analysis:

The local area of ​​the screen can be used only to press inaccurately, but the interruption is normal, and the location of the report is reversed. This phenomenon may be caused by the notebook firmware being too old and not matching the current driver.

3. How to fix:

Upgrade firmware

Screen power supply voltage is abnormal

1. Phenomenon:

Screen cursor irregularly jumps

2. Problem Analysis:

Irregular jumping, indicating that the screen itself is not working properly, this phenomenon will occur when the power supply of the screen is less than its normal working voltage.

3. How to fix:

Modify the screen supply voltage to make it normal, you may need to modify the LDO power supply, the hardware may need to be modified.

Radio frequency interference

1. Phenomenon:

When dialing a call, after the number is dialed out, the button appears to jump.

2. Problem Analysis:

When the phone is called, it appears to be jumping. It indicates that there is interference when making a call. After measuring the working voltage of the screen, it is found that the working voltage of the screen fluctuates up and down.

3. How to fix:

Adjust the screen operating voltage to within the normal operating range

Screen calibration is abnormal

1. Phenomenon:

After pressing the screen in a large area, the call is answered and the touch screen is invalid. You need to press the power button twice to unlock.

2. Problem Analysis:

After pressing the screen in a large area, the screen may be calibrated. At this time, the threshold of the touch response of the screen changes, and the threshold is pressed when the finger is pressed.

After the finger is pressed up, the screen judges that there is no touch event with reference to the previous threshold, so there is no response; when the power button is pressed to sleep and wake up, the screen will be calibrated, and then the normal state is restored, so it can be used.

3. How to fix:

Optimize the screen calibration algorithm to avoid unnecessary calibration, or to calibrate the cutoff time to the normal reference value.