This report represents the circuit analysis of the Texas Instruments BQ2025 single wire interface for the Apple Lightning cable. This device, which incorporates several reference generators, timing and clock generator circuits, and a main controller, receives and transmits security identification signals coming from the 8 pin Lightning cable. It then sends out a clock signal to the external NX20P3 voltage regulator/switch IC that is also located within the Apple lightning cable. The BQ2025 is manufactured in a three metal, two polysilicon, 1 ìm Bi-CMOS process. The die size is measured at 1.24 mm x 0.81 mm (1.00 mm2).