Alpha and Omega Semiconductor Announces Type-C Power Delivery Input Protection Switch with True Reverse Blocking

Smart protection switch provides industry-leading performance, up to 28 V over-voltage protection for Type-C PD port applications

Alpha and Omega Semiconductor (AOS) announced a new USB Type-C Power Delivery compliant input protection switch with up to 28 V over-voltage protection. The AOZ1376 is a smart protection switch with reverse current blocking capability intended for applications where internal circuitry requires protection from exposure to high voltages. This new device offers low R_DS(ON) (20 mohm) in a thermally enhanced 3 × 3 mm DFN package, made possible by AOS’ advanced co-packaging technology, combining a high performance IC with protection features and our latest high SOA MOSFET. The AOZ1376 provides an ideal solution for the latest notebooks, ultra books, dongles, and docking stations, with Thunderbolt/USB Type-C PD ports.

Typically, USB Type-C sinking applications are protected from a reverse current using a circuit that uses two discrete back to back MOSFETs along with resistors and capacitors to provide basic soft start functionality; however programmability and protection features are lacking in this implementation. The AOZ1376 overcomes these disadvantages, saving both component count and PCB footprint while offering a robust protection feature set to increase the reliability of end products using Type-C power delivery.

Functional Block Diagram.

Technical Highlights

The AOZ1376 operates from 3.4 V to 22 V on V_IN. Both V_IN and V_OUT are rated at 28 V Absolute Maximum. The back-to-back switch configuration blocks any current flow between V_IN and V_OUT pins when the device is disabled or when the device is enabled, but V_OUT is greater than V_IN. The AOZ1376 offers programmable soft start and comprehensive protection against short-circuit, thermal overload, reverse voltage and over voltage. The over-voltage protection threshold is selectable by an external resistor. The internal soft-start circuitry controls the inrush current due to highly capacitive loads, and the slew rate can be adjusted using an external capacitor. The device also features robust ESD of ±8 kV on V_IN and V_OUT pins and ±4 kV on all other pins.

Pricing and Availability

The AOZ1376 is immediately available in production quantities with a lead-time of 12 weeks. The unit price of 1,000 pieces is $2.25.