The overwhelming majority of consumers want the convenience of using fewer cords to power their cell phones, MP3 players and other electronic equipment, as well as the flexibility to charge portable equipment from their computers. Because of this market demand, nearly all current and future handheld devices will be able to charge from USB sources. However, USB requirements present several circuit protection challenges for designers of portable equipment. Overvoltage, poor regulation, electromagnetic induction, electrostatic discharge (ESD), incorrect wiring, and reverse voltages are just a few of the events that a USB-enabled device may be exposed to.