This week REWA will walk you through the work-flow of iPhone X Boot Circuit. The boot circuit can be regarded as logic board trigger circuit. To have the phone turned on, working conditions like power supply, clock signal and reset signal are indispensable. What’s more, CPU has to get key components into power-on self-test process and get the bootstrap imported. Since there are so many components involved in the process, reasons for won’t turn on of the phone can also be various.