Thunderbolt 3 and 4 use the USB-C physical connector to carry PCIe x4, DisplayPort 1.4/2.0, USB 3.2, and up to 100W USB Power Delivery. TB4 adds minimum 40 Gbps guarantee and dual 4K or single 8K display support.
| Pin | Name | Function | Type |
|---|---|---|---|
| A1 | GND | Ground | GND |
| A2 | TX1+ | SuperSpeed TX1 positive | BUS |
| A3 | TX1- | SuperSpeed TX1 negative | BUS |
| A4 | VBUS | Power bus | PWR |
| A5 | CC1 | Configuration channel 1 (power/data negotiation) | BUS |
| A6 | D+ | USB 2.0 D+ | BUS |
| A7 | D- | USB 2.0 D- | BUS |
| A8 | SBU1 | Sideband use 1, DP AUX+ in alt mode | BUS |
| A9 | VBUS | Power bus | PWR |
| A10 | RX2- | SuperSpeed RX2 negative | BUS |
| A11 | RX2+ | SuperSpeed RX2 positive | BUS |
| A12 | GND | Ground | GND |
| B1 | GND | Ground | GND |
| B2 | TX2+ | SuperSpeed TX2 positive | BUS |
| B3 | TX2- | SuperSpeed TX2 negative | BUS |
| B4 | VBUS | Power bus | PWR |
| B5 | CC2 | Configuration channel 2 | BUS |
| B6 | D+ | USB 2.0 D+ | BUS |
| B7 | D- | USB 2.0 D- | BUS |
| B8 | SBU2 | Sideband use 2, DP AUX- in alt mode | BUS |
| B9 | VBUS | Power bus | PWR |
| B10 | RX1- | SuperSpeed RX1 negative | BUS |
| B11 | RX1+ | SuperSpeed RX1 positive | BUS |
| B12 | GND | Ground | GND |