Overvoltage Protection Controllers with Reverse Polarity Protection

The MAX4864L/MAX4865L/MAX4866L/MAX4867 overvoltage protection controllers protect low-voltage systems against high-voltage faults up to +28V, and negative voltages down to -28V. These devices drive a low-cost complementary MOSFET. If the input voltage exceeds the overvoltage threshold, these devices turn off the n-channel MOSFET to prevent damage to the protected components. If the input voltage drops below ground, the devices turn off the p-channel MOSFET to prevent damage to the protected components. An internal charge pump eliminates the need for external capacitors and drives the MOSFET GATEN for a simple, robust solution.

The overvoltage thresholds are preset to +7.4V (MAX4864L), +6.35V (MAX4865L), +5.8V (MAX4866L), and +4.65V (MAX4867). When the input voltage drops below the undervoltage lockout (UVLO) threshold, the devices enter a low-current standby mode (8.5µA). Also in shutdown (EN-bar set to logic-high), the current is reduced further (0.4µA). The MAX4864L/MAX4865L/MAX4866L have a +2.85V UVLO threshold, and the MAX4867 has a +2.5V UVLO threshold.

In addition, a ±15kV ESD protection is provided to the input when bypassed with a 1µF capacitor to ground. All devices are offered in a small 6-pin SOT23 and a 6-pin, 2mm x 2mm µDFN package, and are specified for operation over the -40°C to +85°C temperature range.

Applications

* Cell Phones * Digital Still Cameras * MP3 Players * PDAs and Palmtop Devices

* Overvoltage Protection Up to +28V

* Reverse Polarity Protection Down to -28V

* Preset Overvoltage (OV) Trip Level (7.4V, 6.35V, 5.8V, 4.65V)

* Drive Low-Cost Complementary MOSFET

* Internal 50ms Startup Delay

* Internal Charge Pump

* 8.5µA Standby Current (In UVLO Mode)

* 0.4µA Shutdown Current

* Overvoltage Fault FLAG Indicator

* 6-Pin (2mm x 2mm) µDFN and 6-Pin SOT23 Packages