Smart protection switch for Type-C PD port designs
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 has a low RDSON of 20mΩ in a thermally enhanced 3x3mm DFN package.
This is made possible by co-packaging technology that combines a high performance IC with protection features and the latest MOSFET. The AOZ1376 is aimed at notebooks, ultra books, dongles and docking stations that use hunderbolt/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.
“The thinner profile, higher power and greater flexibility offered by USB Type-C and USB PD 3.0 standards have prompted many computer manufacturers to drop the barrel jack in favor of USB Type-C ports for charging their notebook and ultra book offerings; and for the best user experience many of these devices allow the laptop to charge from any of the USB Type-C ports. This makes reverse voltage protection imperative for these devices,” said Mehdy Khotan, Power IC Marketing Director at AOS. “AOZ1376 is used in the Type-C charging path of such devices. It not only protects the laptop and its battery from over voltage and over current, but it also prevents an unintended reverse current and over voltage on the opposite port, protecting the laptop’s peripheral devices.”
The AOZ1376 operates from 3.4V to 22V. Both VIN and VOUT are rated at 28V Absolute Maximum. The back-to-back switch configuration blocks any current flow between VIN and VOUT pins when the device is disabled or when the device is enabled, but VOUT is greater than VIN. 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 ESD of ±8kV on VIN and VOUT pins and ±4kV on all other pins.
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.