The pins of the HDMI interface do not represent the audio signal separately, HDMI can send both audio and video signals at the same time, due to the audio and video signals using the same cable, greatly simplifying the installation of the system wiring.
HDMI is designed to replace older analog signal audio and video transmission interfaces, such as SCART or RCA terminals. It supports a wide variety of TV and computer video formats, including SDTV, HDTV video picture, and multi-channel digital audio.
Expanded Information:
Characteristics of the HDMI Interface:
1. Depending on the Electrical structure and physical shape of the different, HDMI interface can be divided into four types: Type A, Type B, Type C and Type D. Each type of interface includes a socket for the device end and a plug for the cable end. It is driven using a low 5V voltage and all have an impedance of 100 ohms.
2. All of these plugs provide a reliable TMDS connection. Type A is the standard 19-pin HDMI connector with the highest penetration rate. The Type B connector is slightly larger, but with 29 pins, it provides dual TMDS transmission channels, thus supporting higher data rates and Dual-Link DVI connections.
3. The Type C connector offers the same performance as the Type A connector, but is smaller in size and better suited for compact portable devices. Type D is the newest interface mode and is primarily used in cell phones.
Baidu Encyclopedia - HDMI Interface
Baidu Encyclopedia - HDMI Cable