Short-to-VBUS overvoltage and IEC ESD protection solution
01-12-2016 |
Texas Instruments
|
Power
Texas Instruments’ TPD6S300 is a single chip USB Type-C port protection solution that provides 20V Short-to-VBUS overvoltage and IEC ESD protection.
Since the release of the USB Type-C connector, many products and accessories for USB Type-C have been released which do not meet the USB Type-C specification. One example of this is USB Type-C Power Delivery adaptors that only place 20V 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 20V VBUS to be shorted to the CC and SBU pins. Also, due to the close proximity of the pins in the Type-C connector, there is a heightened concern that debris and moisture will cause the 20V VBUS pin to be shorted to the CC and SBU pins.
These non-ideal equipments and mechanical events make it necessary for the CC and SBU pins to be 20V tolerant, even though they only operate at 5V or lower. The device enables the CC and SBU pins to be 20-V tolerant without interfering with normal operation by providing overvoltage protection on the CC and SBU pins. The device places high voltage FETs in series on the SBU and CC 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.
Most systems require IEC 61000-4-2 system level ESD protection for their external pins. The device integrates this protection for the CC1, CC2, SBU1, SBU2, DP, DM pins, removing the need to place high voltage TVS diodes externally on the connector.