The MCP121-450E/TO is a circuit protection device from Microchip that is designed to protect high power DC systems from ESD, EMI and other overvoltage conditions. It has an operating temperature range of -40 to +125 °C and is a low on-resistance IC with an array of diodes and integrated direct current (DC) shields. Normally, the IC is used in battery charger, AC adapter, handheld devices and other high power DC system. The typical maximum operating voltage is up to 450V, the breakdown voltage is up to 700V, and the typical peak pulse current is up to 10A. It features a current limit of 20mA, an adjustable surge suppression threshold voltage, and latch-on protection mode to protect the system and the device itself.