HDMI Interface Comprehensive Analysis：HDMI_A 、HDMI_C（Mini HDMI）、HDMI_D (Micro HDMI)contrast
1. HDMI A Type
Appearance Feature: HDMI_A is the most common black rectangular connector. Its size is approximately 13.9mm × 4.45mm. It has 19 evenly arranged pins, with the top two pins being slightly shorter (ground pins).
The 19-pin layout of HDMI_A type ensures the bandwidth required for high-definition signal transmission, and at the same time reduces the production costs for equipment manufacturers through standardized interfaces. Up to now, mainstream TVs and projectors still mainly use the A-type interface. Some high-end displays' Slim HDMI, 8K HDMI, 48Gbps HDMI, OD 3.0mm HDMI, 144Hz HDMI and other full-function HDMI still rely on the A-type. In addition, designs such as small hdmi cable and hdmi cable 90 degree also provide users with more connection options.
2. HDMI C Type (Mini HDMI)
Appearance features: A flat rectangular interface that is approximately 30% smaller than the A type, with dimensions of 10.4mm × 2.4mm and also a 19-pin design.
The bandwidth is the same as that of the A model. It supports all the functions of the A model (3D video, 4K@30Hz, audio return channel ARC, etc.), but it needs to be connected to the TV through a conversion cable such as mini HDMI to HDMI cable or Right Angle MINI HDMI CABLE. Currently, there are also MINI HDMI Cables that support mini HDMI 2.0 and 8K HDMI on the market, meeting the requirements for high-quality transmission.
Although the C type is smaller in size, the A type still dominates the market due to its lower cost and broader compatibility. It was not until the D type emerged that the miniaturization of interface for portable devices truly reached its limit.
3. HDMI D Type (Micro HDMI)
The HDMI D type is actually Micro HDMI, which is the smallest version of the HDMI interface and is mainly used in portable devices. Its physical size is only 6.4×2.8mm, shrinking by approximately 72% compared to the standard HDMI A type. However, it fully supports all the functions of HDMI 1.4 and above, including 4K resolution, 3D imaging, Ethernet channel, and audio return ARC.
The interface also adopts a 19-pin design, with pin definitions compatible with standard HDMI. It can be converted to a standard interface through micro HDMI to HDMI cables or 90 MICRO HDMI Cables and other adapters. In recent years, MICRO HDMI Cables supporting 8K Micro HDMI and micro HDMI 2.0 have also emerged, suitable for professional image transmission.
Typical application scenarios include: motion cameras, drone video transmission equipment, tablet computers, and other mobile terminals with limited space.
The mechanical strength of the HDMI D-type interface is relatively low, approximately half that of the standard interface.
With the widespread adoption of USB-C interfaces, some new devices have switched to using USB-C instead. However, professional imaging equipment still retains the D-type interface to meet the precise timing requirements.
Post time: Sep-25-2025
