19 pin HDMI type A connector.
HDMI (High-Definition Multimedia Interface) is a digital audio/video interface that carries uncompressed video and audio together with control signals over a single cable, between a source (such as a player, console or PC) and a display. It is electrically compatible with single-link DVI, so the two can be joined with a passive adapter or cable, though HDMI’s audio and control features are then unavailable.
The standard Type A connector has 19 pins. A 29-pin Type B connector was defined to carry a dual-link (expanded) video channel for resolutions beyond 1080p, but it was never adopted commercially — later HDMI versions instead raised the bandwidth of the single TMDS link. The smaller 19-pin mini (Type C) and micro (Type D) connectors share the Type A pin functions.
Type A
| Pin | Signal | Description |
|---|---|---|
| 1 | TMDS Data2+ | |
| 2 | TMDS Data2 Shield | |
| 3 | TMDS Data2– | |
| 4 | TMDS Data1+ | |
| 5 | TMDS Data1 Shield | |
| 6 | TMDS Data1– | |
| 7 | TMDS Data0+ | |
| 8 | TMDS Data0 Shield | |
| 9 | TMDS Data0– | |
| 10 | TMDS Clock+ | |
| 11 | TMDS Clock Shield | |
| 12 | TMDS Clock– | |
| 13 | CEC | |
| 14 | Reserved | N.C. on device |
| 15 | SCL | |
| 16 | SDA | |
| 17 | DDC/CEC Ground | |
| 18 | +5 V Power | |
| 19 | Hot Plug Detect |
Type B
| Pin | Signal | Description |
|---|---|---|
| 1 | TMDS Data2+ | |
| 2 | TMDS Data2 Shield | |
| 3 | TMDS Data2- | |
| 4 | TMDS Data1+ | |
| 5 | TMDS Data1 Shield | |
| 6 | TMDS Data1- | |
| 7 | TMDS Data0+ | |
| 8 | TMDS Data0 Shield | |
| 9 | TMDS Data0- | |
| 10 | TMDS Clock+ | |
| 11 | TMDS Clock Shield | |
| 12 | TMDS Clock- | |
| 13 | TMDS Data5+ | |
| 14 | TMDS Data5 Shield | |
| 15 | TMDS Data5- | |
| 16 | TMDS Data4+ | |
| 17 | TMDS Data4 Shield | |
| 18 | TMDS Data4- | |
| 19 | TMDS Data3+ | |
| 20 | TMDS Data3 Shield | |
| 21 | TMDS Data3- | |
| 22 | CEC | |
| 23 | Reserved | (N.C. on device) |
| 24 | Reserved | (N.C. on device) |
| 25 | SCL | |
| 26 | SDA | |
| 27 | DDC/CEC Ground | |
| 28 | +5V | |
| 29 | Hot Plug Detect |
Notes
- TMDS channel carries audio, video and auxiliary data.
- Signalling method: According to DVI 1.0 spec. Single-link (Type A HDMI) or dual-link (Type B HDMI).
- Video pixel rate: 25 MHz to 165 MHz (Type A) or to 330 MHz (Type B).
- Video formats with rates below 25 MHz (e.g. 13.5 MHz for 480i/NTSC) transmitted using a pixel-repetition scheme.
- Up to 24 bits per pixel can be transferred, regardless of rate.
- Supports 1080p60.
- Pixel encodings: RGB 4:4:4, YCbCr 4:4:4 (8 bits per component); YCbCr 4:2:2 (12 bits per component).
- Audio sample rates: 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96kHz, 176.4 kHz, 192 kHz, up to 8 audio channels .
- Type A HDMI is backward-compatible with the single-link Digital Visual Interface (DVI) used on modern computer monitors and graphics cards. This means that a DVI source can drive an HDMI monitor, or vice versa, by means of a suitable adapter or cable, but the audio and remote control features of HDMI will not be available. Additionally, without support for HDCP, the video quality and resolution may be artificially downgraded by the signal source to prevent the end user from viewing or especially copying restricted content. Type B HDMI is similarly backward-compatible with dual-link DVI.