The NCP346 from ON Semiconductor is an overvoltage protection circuit (OVP) optimized for applications with an external ac-dc adapter, a car charger accessory
The NCP346 from ON Semiconductor is an overvoltage protection circuit (OVP) optimized for applications with an external ac-dc adapter, a car charger accessory and/or a battery recharger. Delivering superior voltage capability and faster turn-off speed than standard CMOS supervisory circuits, the device is suitable for cell phone, digital camera, portable computer, PDA and portable CD player applications.
The NCP346 OVP circuit is a key component in a battery charging system specifically intended to protect sensitive charging electronics from high-voltage events detected on the input by quickly disconnecting them from the adapter. The rugged BiCMOS process on which the NCP346 is built enables it to turn off a series PFET in less than 1 µs and withstands up to 30 V of overvoltage transients (or 25-V steady state). The only competitive device options for the NCP346 are low-voltage CMOS supervisors that have voltage ratings only as high as 12 V and turn-off times in the range of 200 µs for comparable capacitive loads.