The FA2218 is a single-chip USB Type-C port protection device that provides 48V Short-to-VBUS protection. Since the release of the USB Type-C connector, many products and accessories for USB Type-C have been released that do not meet the USB Type-C specification. One example of this is USB Type-C Power Delivery
adaptors that only place 48V on the VBUS line. Another concern for USB Type-C is that mechanical twisting and sliding of the connector could short pins due to the close proximity they have in this small connector. This can cause 48V VBUS to be shorted to the CC and SBU pins. Also, due to the proximity of the pins in the Type-
C connector, there is a heightened concern that debris and moisture will cause the 48V VBUS pin to be shorted to the CC and SBU pins.
These non-ideal equipment and mechanical events make it necessary for the CC and SBU pins to be 48V tolerant, even though the pins only operate at 5V or lower. The FA2218 enables the CC and SBU pins to be 48V tolerant without interfering with normal operation by providing over-voltage protection on the CC and SBU pins. The device places high voltage FETs in series on the CC and SBU lines. When a voltage above the OVP threshold is detected on these lines, the high voltage switches are opened up, isolating the rest of the system from the high voltage condition present on the connector.
The integrated VBUS divider circuit and FET driver, allow PD controllers not rated for EPR operation to safely operate in EPR voltage ranges. When enabled by GPIO or automatically when VBUS exceeds 24V, the FA2218 disables the optional external blocking FET and enables the voltage divider. This action protects 20V rated PD controllers and allows the use of existing VBUS sense circuits.