72V Integrated Overvoltage Protectors with Always-On 100mA Linear Regulator Are Ideal for Automotive Applications
| Note to Editor: The MAX6397/MAX6398/MAX6399 are low-power, integrated automotive overvoltage protectors capable of handling voltages up to 72V. These devices provide the necessary protection and reduce system cost by allowing use of lower input-voltage DC-DC regulators. The MAX6397/MAX6398/MAX6399 can be configured as a switch controller that turns off an n-channel switch after an overvoltage condition, or they can operate in a voltage-limiter mode that regulates the output to allow for continuous operation. An internal charge pump ensures that the n-channel switch is fully enhanced during normal operating mode. The MAX6397 also offers an additional independent always-on linear regulator that can deliver up to 100mA current with fixed-output options of 5V, 3.3V, 2.5V, and 1.8V. The MAX6399 offers undervoltage monitoring. All devices are offered in a small, 3mm x 3mm TDFN package and are fully specified for the automotive temperature range from -40°C to +125°C. |
SUNNYVALE, CA-May 26, 2005-Maxim Integrated Products (NASDAQ: MXIM) introduces 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 quickly 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 features 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 degrees Celsius to +125 degrees Celsius automotive temperature range. Evaluation kits are available from the factory. Prices start at $1.23 (1000-up, FOB USA).
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