All HDMI Connector Pinout Explained(A,B,C,D)

HDMI is a very popular audio-visual interfacing standard used in many devices. It enables the transmission of audio and visual data through a single cable with an ultra-high resolution.

Different types of HDMI connectors are now available in the market. Also, the devices incorporate the HDMI port based on convenience in specification and space. Let’s see the pinout diagrams and connections of the most significant HDMI connector types.

HDMI Pinout

C-More Micro HMI Hardware Unboxing ...
C-More Micro HMI Hardware Unboxing and Review

Type A, B, C, D, and E are the different HDMI connector types. Except for Type B, all connectors have 19 pins but they vary in size and specifications. Among these 5 types, HDMI A, C, and D are the most widely used HDMI connectors.

The figure below shows the pinout of the HDMI connector(A, C, D). The 19 pins are allocated as two rows. The numbering starts from the right and progresses alternatively between the top and bottom rows.

Now let’s see how the signaling differs among Type A, C, and D HDMI connectors.

Note: The pinout shown here is of HDMI connectors and not of HDMI ports. Their pinout is identical but exactly opposite of each other i.e, pin 1 of the HDMI connector is pin 19 on the HDMI port.

Type A HDMI connector Pinout

Type A HDMI connector pinout
Type A HDMI connector pinout

Type A is the standard HDMI connector. The size of the male connector is 13.9 mm × 4.45 mm and that of the female connector is 14 mm × 4.55 mm. This is the largest connector type. The signal description is given in the table below.

Pin NumberSignal NamePin NumberSignal Name
1TDMS Data 2+11TDMS Clock Shield
2TDMS Data 2 Shield12TDMS Clock-
3TDMS Data 2-13CEC
4TDMS Data 1+14No connection
5TDMS Data 1 Shield15DDC Clock
6TDMS Data 1-16DDC Data
7TDMS Data 0+17Ground
8TDMS Data 0 Shield18+5V Power
9TDMS Data 0-19Hot Plug Detect
10TDMS Clock+
Type A HDMI connector pinout

Type C(Mini) HDMI connector Pinout

Type C HDMI connector pinout
Type C HDMI connector pinout

Type C is also called Mini HDMI Connector. The size of the mini connector is 10.42mm × 2.42mm.

The pin description of the Type C HDMI connector is given below:

Pin NumberSignal NamePin NumberSignal Name
1TDMS Data 2 Shield11TDMS Clock+
2TDMS Data 2+12TDMS Clock-
3TDMS Data 2-13DDC/CEC Ground
4TDMS Data 1 Shield14CEC
5TDMS Data 1+15SCL (DDC lock)
6TDMS Data 1-16SDA (DDC data)
7TDMS Data 0 Shield17HEC+
8TDMS Data 0+18+5V Power
9TDMS Data 0-19Hot Plug Detect/HEC-
10TDMS Clock Shield
Type C HDMI connector pinout

Note: The pinout of the mini connector is almost similar to the standard A connector, except for a few changes.

  • The positive signal and the corresponding shield signals are swapped in each set.
  • Pin 13 is DDC/CEC instead of pin 17
  • Pin 14 is CEC instead of 13
  • Pin 17 is an additional pin connected to HEC

Type D(Micro) HDMI connector Pinout

Type D HDMI connector pinout
Type D HDMI connector pinout

Type D is also called Micro HDMI Connector. The size of this connector is 5.83 mm x 2.2 mm. This is the smallest HDMI connector.

Although it is the smallest, it also maintains 19 pins and retains all the basic functionalities. But the order of signaling is slightly different, which is given in the table below.

Pin NumberSignal NamePin NumberSignal Name
1Hot Plug Detect/HEC-11TDMS Data 0-
2Utility/HEAC+12TDMS Clock+
3TDMS Data 2+13TDMS Clock Shield
4TDMS Data 2 Shield14TDMS Clock-
5TDMS Data 2-15CEC (Control)
6TDMS Data 1+16DDC/CEC/HEAC Ground
7TDMS Data 1 Shield17SCL (DDC clock)
8TDMS Data 1-18SDA (DDC data)
9TDMS Data 0+19+5 V Power (power EDID/DDC)
10TDMS Data 0 Shield

Type B HDMI connector Pinout

Type B is the Dual-link HDMI connector. To support this extra feature, it has 29 pins while all other connector types have 19 pins. But this connector was not used in any devices since the newer HDMI version(1.3) does not support this dual link property.

The pinout description of HDMI type B is given in the table below.

Pin NumberSignal NamePin NumberSignal Name
1TDMS Data 2 +16TDMS Data 4 +
2TDMS Data 2 Shield17TDMS Data 4 Shield
3TDMS Data 2 –18TDMS Data 4 –
4TDMS Data 1+19TDMS Data 3 +
5TDMS Data 1 Shield20TDMS Data 3 Shield
6TDMS Data 1-21TDMS Data 3 –
7TDMS Data 0+22CEC
8TDMS Data 0 Shield23Reserved
9TDMS Data 0 –24Reserved
10TDMS Clock+25SCL
11TDMS Clock Shield26SDA
12TDMS Clock-27DDC/CEC Ground
13TDMS Data 5 +28+5V Power
14TDMS Data 5 Shield29Hot Plug Detect
15TDMS Data 5 –

Pin description of HDMI connector

The pinout description of HDMI connectors has several abbreviations. It is essential to know what they denote for a proper understanding of the signaling of the connectors.

TDMS, CEC, DDC, HEC, HEAC, SCL, SDA, and EDID are the abbreviations included in the pinout. Most of these are actually different communication channels used in HDMI technology. Let’s see them in detail.

  1. Transition Minimized Differential Signaling (TMDS) The HDMI cable carries three (six, in the case of Type B) TDMS data channels numbered 0, 1, and 2. These channels are meant for the transmission of video, audio and auxiliary data as separate packet types.
  2. Consumer Electronics Control (CEC) This channel is meant for the command and control of the user for up to 15 devices.
  3. Display Data Channel (DDC) This channel is meant for communication between the display monitor and the PC. DDC communication is based on I2C (Inter-Integrated Circuit) bus specification.
  4. HDMI Ethernet Channel (HEC) The channel allows the devices connected to HDMI to access the internet without using separate Ethernet cables. It is transmitted as a differential signal.
  5. HDMI Ethernet and Audio Return Channel (HEAC) It was introduced in HDMI 1.4. This channel is used for high-speed bi-directional data communication. It used two pins of the connector: an unused pin and the hot plug detect pin
  6. I2C Serial Clock for DDC (SCL)
  7. I2C Serial Data for DDC (SDL)
  8. Extended Display Identification (EDID) It is a signal transmission standard that enables the display devices to communicate with the video source.

Leave a Comment