17 touch screen displays.The four-wire touch screen contains two resistive layers. One layer has a vertical bus at the left and right edges of the screen, and the other layer has a horizontal bus at the bottom and top of the screen, as shown in Figure 4 . To measure in the X- axis direction, the left bus is biased to 0V and the right bus is biased to VREF . Connect the top or bottom bus to the ADC to make a measurement when the top and bottom layers are in contact.

17 touch screen displays.The four-wire touch screen contains two resistive layers. One layer has a vertical bus at the left and right edges of the screen, and the other layer has a horizontal bus at the bottom and top of the screen, as shown in Figure 4 . To measure in the X- axis direction, the left bus is biased to 0V and the right bus is biased to VREF . Connect the top or bottom bus to the ADC to make a measurement when the top and bottom layers are in contact. IQTouch K interactive touch screen feature 20-point touch and dual system -- Android 8.0 system and optional OPS Windows 10Pro system. Its 4K UHD resolution facilitates presentations and collaboration. With optional multi-screen casting software, IQClass 6.0 and installation-free IQClass Plus software, IQTouch K Series can help create an interactive and collaborative teaching atmosphere in class.