MAXIM Integrated Products, represented by Arrow Electronics , has released the MAX6397/MAX6398/MAX6399 overvoltage protectors for systems with high transient voltages as in automotive and industrial applications.
The MAX6397/MAX6398/MAX6399 operate from 5.75V to 72V. The parts can be configured either as a switch controller that turns off an external n-channel switch during an overvoltage condition, or as a voltage limiter that regulates the output to allow continuous operation.
An adjustable threshold allows two external resistors to set the overvoltage threshold level. An internal charge pump ensures that the n-channel switch is fully enhanced during normal operating mode. In the switch-controller mode, the n-channel MOSFET is quickly shut off as the MOSFET's gate is pulled down through an internal current source. In the voltage-limiting mode, the MOSFET is turned on and off to maintain a regulated voltage at the output. These devices provide the necessary protection and reduce system cost by allowing use of lower input-voltage dc-dc regulators.
The MAX6397 has an independent always-on linear regulator that can deliver up to 100mA output current with four fixed-output options of 5V, 3.3V, 2.5V and 1.8V. This device also has a power-good indicator.
The MAX6399 offers both an undervoltage and overvoltage threshold with a power-good indicator. An overvoltage latch mode keeps the n-channel MOSFET off until the power is recycled or the shutdown input is toggled. Other MAX6399 features include a shutdown input for manually shutting off the n-channel switch and thermal shutdown protection.
All three devices are offered in a small, 3mm x 3mm TDFN package and are fully specified from the -40°C to 125°C automotive temperature range.