interactive touch screen design.The 5V voltage is provided by an external power supply, and a part of it is mainly provided to the driving chip 74HC595 of the infrared transmitting circuit , and drives all the infrared transmitting tubes. It also needs to provide the driving chip ADS7830 of the infrared receiving circuit . The other part is converted into 3.3V and provided to the microprocessor chip LPC2132, serial communication interface chip Max3490. It made to the current in the infrared emission Each 10-100mA between changes , so must meet the external power module output current . 2A . In the 5 V to 3.3 V circuit is obtained by the SPX1117M 3 and the filter circuit output. Among them , SPX 1117M3 is produced by Sipex Company , the output current can reach 800mA, the output voltage accuracy is within1% , and it also has current limit and thermal protection functions. The SPX1117 series chip has very low quiescent current, and its low dropout voltage is only at full load.1.1V, when the output current decreases, the quiescent current variation with the load , and improve efficiency. The conversion circuit is as follows:

interactive touch screen design.The 5V voltage is provided by an external power supply, and a part of it is mainly provided to the driving chip 74HC595 of the infrared transmitting circuit , and drives all the infrared transmitting tubes. It also needs to provide the driving chip ADS7830 of the infrared receiving circuit . The other part is converted into 3.3V and provided to the microprocessor chip LPC2132, serial communication interface chip Max3490. It made to the current in the infrared emission Each 10-100mA between changes , so must meet the external power module output current . 2A . In the 5 V to 3.3 V circuit is obtained by the SPX1117M 3 and the filter circuit output. Among them , SPX 1117M3 is produced by Sipex Company , the output current can reach 800mA, the output voltage accuracy is within1% , and it also has current limit and thermal protection functions. The SPX1117 series chip has very low quiescent current, and its low dropout voltage is only at full load.1.1V, when the output current decreases, the quiescent current variation with the load , and improve efficiency. The conversion circuit is as follows: 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.