Maxim’s Accurate Overvoltage Protectors with Active Current Limiting

Maxim Integrated Products has introduced its MAX4978-MAX4981 overvoltage protectors (OVPs) with active current limiting. They protect low-voltage systems against voltage faults up to 28V with 5.7V and 6.8V threshold options. The active current limiter provides a second layer of defense for the protected device and is available in 0.9A and 1.95A threshold options. Designed to protect the charger input port of portable devices, these OVPs are ideal for cell phones, MP3 players, digital still cameras (DSCs), and PDAs. The MAX4978-MAX4981 provide ±15kV ESD input protection when a 1microfarad ceramic capacitor is connected from Vin to ground. Additionally, the MAX4980/MAX4981 include battery-overcharge protection that monitors the voltage on the Li-ion battery being charged. Once this monitored voltage reaches 4.4V, the switch is disconnected to avoid overcharging. Packaged in a lead-free, 2mm x 3mm, 8-pin TDFN with an exposed pad, the MAX4978-MAX4981 are fully specified over the -40 degrees Celsius to +85 degrees Celsius extended temperature range. Prices start at $1.47 (1000-up, FOB USA).