This schematic and Gerber files of PCB that is used for GPS tracking device with GSM link. Scheme has many valuable schematic features, like protected digital and analog I/Os, power part adapted for car power supply, etc. Can be used as a refere

This schematic and Gerber files of PCB that is used for GSM alarm system. This is industrial-grade system with many features like 1-wire (iButton) interface, additional interface for video camera (UART JPEG camera is used), SD card to store pictures

SIMCOM hardware design guide line for engineer to make schematic and pcb